Following are definitions of key scientific terms, as derived primarily from Borror (1960), Borror et al. (current running dates),
Brown (1954), Carpenter (1938), Dorland (1932), Hanson (1959), Henderson & Henderson (1939), and Huber & Sharkey (1993)
[see latter for illustrations], Jaeger (155), Jardine (1913), Pennak (1964), Smith (1906), Snodgrass (1935), Torre-Bueno (1937), Tuxen
(1970) and Tweney & Hughes (1940).
Please CLICK on FIRST LETTER of desired subject:
[Search by depressing Ctrl/F and type-in word.]
abdomen (adj., abdominal). (Hymenoptera) The principal posterior division of the body, posterior to the leg-bearing
segments and composed of 10 or fewer apparent segments; in most Symphyra abdominal segment 1 is easily
recognized by its median split (cf. metasoma, propodeum). The posterior of three body regions.
abscissa (pl. abscissae). A segment of a wing vein that is delimited by the intersection of other veins.
accessory vein An extra branch of a longitudinal vein (indicated by a subscript a; for example, an accessory of M, is designated Ml.
accessory pulsatile organ Contractile organs that function to move hemolymph into and out of appendages.
accessory cell. A closed cell in the front wing of Lepidoptera formed by the fusion of 2 branches of the radius, usually
the R-2 cell
accessory gland A secretory organ associated with the reproductive system; a gland associated with reproductive
organs or either males of females and producing substances accompanying the sperm or eggs.
accessory pulsatile organ. Contractile organs that function to move hemolymph into and out of appendages.
accessory vein. An extra branch of a longitudinal vein (indicated by a subscript "a").
acrosternite. The portion of a sternum anterior to the antecostal suture.
acrostichal bristles. One or more longitudinal rows of small bristles along the center of the mesonotum in Diptera.
acrotergite. The portion of a tergum anterior to the antecostal suture.
aculea (pl., aculeae). Minute spines on the wing membrane in Lepidoptera.
aculeate. With aculea in Lepidoptera or a sting in Hymenoptera.
acuminate. Tapering to a long point.
acute Pointed; forming an angle of less than 90°. Sharply angled, less than 90°
adecticous A type of pupa in which the mandibles are immovable and nonfunctional.
adfrontal areas. A pair of narrow oblique sclerites on the head of a lepidopterous larva.
adventitious vein A secondary vein, neither accessory nor intercalary, usually the result of cross veins lined up to form
a continuous vein. A wing vein that is not homologized with a standard wing vein.
aedeagus. The sclerotized median intromittent organ of a male insect. The male intromittent organ; the distal part of
the phallus; penis plus parameres.
aeropile. the opening in the chorion (egg shell) through which air enters, often covered by a plastron.
aestivation. Dormancy during a warm or dry season.
agamic. Reproducing parthenogenetically (without mating).
alinotum. The notal plate of the mesothorax or metathorax of a pterygote insect.
allometric growth. A genetically determined tendency for a certain body part to grow at a more rapid rate than other
allomone. An external chemical signal that acts between different species to benefit the producer; e.g., to repel a
predator or parasitoid.
alula (pl., alulae). A lobe at the base of the wing in Diptera; see calypter.
ametabolous Without metamorphosis (= changing little in form during the course of growth and molting).
amphipneustic. Only prothoracic and posterior abdominal spiracles present.
anal Pertaining to the last abdominal segment (which bears the anus!; the posterior basal part Ifor example, of the wing.
anal crossing. Where A branches posteriorly from Cu+A in Odonata.
anal cell. A cell in the anal area of the wing; cell 1A of Diptera.
anal area of the wing The posterior portion of the wing, usually including the anal veins.
anal lobe. A lobe in the posterior basal part of the wing.
anal loop. A group of cells in the hind wing of dragonflies between Cu-2, 1A, and 2A which may be rounded,
elongated or foot-shaped.
analogy Similarity in function filling a common need but having a different evolutionary origin.
anamorphosis. Development of an organism in which one or more body segments are added posteriorly at each molt.
anapleurite. The upper and outer of the two incomplete subcoxal rings that form the thoracic pleurites.
anelli. ring-like segments
anelliform . ring-like
anellus. ring-like sgement
anemotaxis. Orientation with respect to currents in the air.
anepimeron. The portion of the anapleurite posterior to the pleural suture.
anepisternum. The portion of the anapleurite anterior to the pleural suture.
anisomorphal. A defensive allomone of the walkingstick Anisomorpha.
annulate. Ringed; formed in ring-like segments or color patterns.
annulated With ringlike segments or divisions.
anteapical Just proximad of the apex.
anteapical cell. A cell in the distal part of the wing of leafhoppers.
anteapical. Just proximal of the apex.
anteclypeus. An anterior division of the clypeus.
antecosta (pl., antecostae). An internal ridge on the anterior portion of a tergum or sternum that serves as the site of
attachment of the longitudinal muscles.
antecostal sclerite. A sclerite of the metasternum, just anterior to the hind coxae.
antecostal suture. An external groove that marks the position of the internal antecosta.
antecoxal sclerite A sclerite of the metasternum, just anterior to the hind coxae.
antenna (pl., antennae; adj., antennal). A paired, segmented sensory appendage of the head between the compound
eyes, which consists of 3 segments having intrinsic muscles and usually sensory in function.
antennal club The enlarged distal segments of a clubbed antenna.antennal fossa. A cavity or depression in which the
antennae are located.
antennal groove. A groove in the head capsule into which the basal segment of the antenna fits.
antennule The first antennae of Crustacea.
antenodal cross veins. Cross veins along the costal border of the wing, between the base of the wing and the nodus,
extending from the costa to the radius (Odonata).
antepenultimate. The 3rd from the last.
antepygidial bristle. One or more large bristles on the apical margin of the 7th (next to last) tergum in Siphonaptera.
anterior. Front; in front of.
antepygidial bristle One or more large bristles on the apical margin of the seventh (next to the last) tergum
anterior Front; in front of.
anterior cross vein. The r-m cross vein in Diptera.
anterodorsal In the front and at the top or upper side.
anteromesal. In the front and along the midline of the body.
anteroventral. In the front and underneath or on the lower side.
antibiosis. Any deleterious effect on insect survival resulting from feeding on a resistant host.
anus. The posterior opening of the alimentary tract.
aorta. A blood-containing tube in insects that extends forward from the heart and is open anteriorly (nonpulsatile
portion of the dorsal blood vessel). The anterior nonpulsatile portion of the dorsal blood vessel.
apex (pl., apices; adj., apical, apico-). Part of a structure most remote from its point of attachment to the body.
apical At the end, tip, or outermost part.
apical cell. A cell near the wing tip
apical cross vein. A cross vein enar the apex of the wing (Plecoptera, Homoptera).
apodeme An invagination of the body wall forming a rigid process that serves for muscle attachment and for the
strengthening of the body wall. apolysis The separation of the epidermis from the cuticle (part of the process
of moltingl. An invagination of the exoskeleton that serves as a point of muscle attachment.
apolysis. Retraction of the epidermal cells from the inner surface of the endocuticle, the first step in molting.
apophysis (pl., apophyses). A tubercular or elongated process of the body wall, either external or internal.
aposematism. Possession of vivid coloration that identifies an insect as having distasteful or unpleasant properties.
appendix. A supplementary or additional piece or part (eg., homopteran wing).
appetitive behavior. Searching behavior of variable pattern, seeking an appropriate stimulus.
apposition eye. A type of compound eye occuring in diurnal insects, in which each ommatidium is surrounded by a
shield of pigment.
apterygote. A wingless insect of a group believed never to have had wings in its history (primitively wingless
aquatic. Living in water.
arcuate. Bent like a bow, or arched.
arculus. A basal cross vein between the radius and the cubitus in Odonata.
areola (pl., areolae; adj., areolate). In Ichneumonidae, the median area of the propodeum that is enclosed by ridges.
areole An accessory cell Isee also basal areolel.
areolet. In Ichneumonidae, the small cell in the center of the forewing (submarginal cell opposite the 2nd m-cu cross vein); the 1st radial sector cell.
arista. A large bristle, usually dorsally located, on the apical antennal segment in Diptera.
aristate. Bristlelike, with an arista; aristate antenna.
arolium (pl., arolia). A pad-like median lobe between the tarsal claws (also see pretarsus). A padlike structure at the
apex of the last tarsal segment, between the claws (Orthoptera); a padlike structure at the base of each tarsal
arrhenotoky A form of parthenogenesis in which females are produced from fertilized eggs, males from unfertilized
articulation. A joint as between 2 segments or structures.
aspirator A device with which insects may be picked up by suction.
associative learning. Acquisition of the capacity to associate a stimulus with a reward (or punishment).
asymmetrical Not alike on the two sides.
asynchronous muscle A rapidly contracting muscle in which the individual contractions are not initiated by a neuronal
impulse (compare synch‑onous orneurogenic musclel .
atrium (pl., atnal A chamber; a chamber just inside a body opening.
atrophied Reduced in size, rudimentary.
attenuated. Very slender and gradually tapering distally.
auricle. A small lobe or earlike structure (Hymenoptera).
autocidal control. The use of insects for self destruction, mostly by release of sterile individuals.
autogenous. In blood-feeding insects, the ability to produce eggs without taking blood (as some mosquitoes).
auxiliary vein. The subcosta (Diptera)
axilla (pl., axillae; adj., axillar). In groups with a transscutal articulation, posterolateral portion of the mesoscutum
separated from the mesoscutum lateral to the scutellum; usually triangular (also see scutum). A triangular or
rounded sclerite laterad of the scutellum and usually just caudad of the base of the front wing (Hymenoptera).
axillary cell A cell in the anal area of the wing (Diptera & Hymenoptera)
axillary sclerite A small sclerite at the wing base that articulates with the thorax.
axillary sclerites The small sclerites at the base of the wing that translate deformations of the thorax into movements.
axillula (pl., axillulae; adj., axillular). In Chalcidoidea, the lateral subdivision of the scutellum delimited by a
axon. A fiber of a nerve cell that carries nerve impulses away from the cell body.
binominal nomenclature The system of naming organisms with two names, generic and specific.
biological control The employment of biotic agents, such as predators, parasitoids, and disease organisms, to control
band A transverse marking broader than a line.
basal areole A small cell at the base of the wing; the cell at the base of the wing between Sc and R (Lepidoptera)
basal anal cell An anal cell near the wing base; a cell at the base of the wing between IA and 2A (Plecoptera)
basal cell A cell near the base of the wing, bordered at least in part by the unbranched portions of the longitudinal
veins; in the Diptera, one of the two cells proximad of the anterior cross vein and the discal cell (Diptera).
basal vein A vein in about the middle of the front wing, extending from the median vein to the subcostal or cubital
vein; the first free segment of M (Hymenoptera).
basalare lor basalar sclerite1 An epipleurite located anterior to the pleural wing process.
base (pl., basal, basi-). Part of a structure closest to its point of attachment to the body.
basement membrane A noncellular membrane underlying the epidermal cells of the body wall.
basisternum That part of a thoracic sternum anterior to the sternacostal suture.
basitibial plate. In Apoidea, a small flat, hairless, raised region of the dorsal surface of the metatibia at its base.
beak The protruding mouthpart structures of a sucking insect; proboscis.
bifid Forked, or divided into two parts.
bilateral symmetry See symmetry
bilobed Divided into two lobes
biotic release The sudden release of a population from its natural enemies, often resulting in a population explosion.
biotype A population of a species that differs genetically from another population with respect to host affiliation (also
called "host race").
bipectinate Having branches on two sides like teeth of a comb.
biramous With two branches; consisting of an endopodite and an exopodite ICrustaceal.
bisexual With males and females.
bituberculate With two tubercles or swellings.
bivalved With two valves or parts, clamlike.
bivoltine Having two generations per year.
blastoderm The thin cellular layer that surrounds the yolk of an egg.
bombyko The sex attractant pheromone of the female silkworm moth.
blastoderm The peripheral cell layer in the insect egg following cleavage.
book gills The leaflike gills of a horseshoe crab.
book lung A respiratory cavity containing a series of leaflike folds Ispiders).
borrow pit A pit formed by an excavation, where earth has been "borrowed" for use elsewhere. boss A smooth lateral
prominence at the base of a chelicera Ispiders).
brace vein A slanting cross vein; in Odonata, a slanting cross vein just behind the proximal end of the stigma.
brachypterous With short wings that do not cover the abdomen.
brain. anterior ganglion of the nervous system, located above the esophagus; in insects composed of the
protocerebrum, deutocerebrum, and tritocerebrum.
brain hormone A chemical messenger produced by neurosecretory cells in the brain that activates the prothoracic
glands to produce ecdysone jalso known as PTTH or prothoracicotropic hormone).
brevicomin An aggregation pheromone of the bark beetle dendroctonus ore~icomis.
bridge cross vein A cross vein anterior to the bridge vein (Odonata).
bridge vein The vein that appears as the basal part of the radial sector, by M, and the oblique vein (Odonata).
brood The individuals that hatch from the eggs laid by one mother; individuals that hatch at about the same time and
normally mature at about the same time.
bucca (pl., buccael) A sclerite on the head below the compound eye and iust above the mouth opening (Diptera)
buccal cavity The opening enclosed by the mouthparts, leading to the true mouth and the pharynx.
buccula (pl, bucculae) One of two ridges on the underside of the head, on each side of the beak (Hemiptera).
bulla (pl., bullae). In Ichneumonidae, unpigmented area of a vein where it is crossed by a wing fold or line of flexion.
bursa copulatrix A pouch of the female reproductive system that receives the male genitalia during copulation.
bursa copulatrix A pouch on the median oviduct of the female that receives the aedeagus of the male.
bursicon The hormone controlling tanning and expansion, produced by neurosecretory cells of the brain.
bursicon A hormone involved in the process of sclerotization.
caecum (pl., caecae) A saclike or tubelike structure, open at only one end.
calamistrum One or two rows of curved spines on the metatarsus of the hind legs of spiders.
calcaria Movable spurs at the apex of the tibia.
callus (pl., callil A rounded swelling.
calypter (pl., calypteres) One or two small lobes at the base of the wing, located just above the haltere (Diptera) (also
camera lucida A device enabling one to make accurate drawings of objects seen through a microscope; when it is
attached to the eyepiece of a microscope; the observer can see the object under the microscope and his or her
drawing paper at the same time.
campaniform sensillum A sense organ consisting of a dome‑shaped portion of the cuticle with associated sensory
neuron; perceives stresses in the cuticle. A sense organ consisting of a dome‑shaped cuticular area into which
the sensory cell process is insertcd like the clapper of a bell.
campodeiform larva A larva shaped like the dipluran Campodea (that is, elongate and flattened), with well‑developed
legs and antennae, and usually active.
cantharidin A defense allomotle of blister beetles (also known as "Spanish fly").
capitate With an apical knoblike enlargement; capitate antenna.
carapace A hard dorsal covering consisting of fused dorsal sclerites (Crustacea)
cardo (pl., cardines) The basal segment or division of a maxilla; one of two small laterobasal sclerites in the millipede
cardo (pl., cardines). The basal part of the maxilla.
carina (pl., carinae; adj., carinate). A ridge or raised line.
carinate Ridged or keeled.
carnivorous Feeding on the flesh of other animals.
caste A form or type of adult in a social insect (termites &ants).
catapleurite The lower and inner of the two incomplete subcoxal rings that form the thoracic pleurites lalso called the
catepleurite, katepleurite, and coxopleurite.
catepimeron The portion of the catapleurite posterior to the pleural suture.
catepistetnum The portion of the catapleurite anterior to the pleural sulcus.
caterpillar An eruciform larva; the larva of a butterfly, moth, sawfly, or scorpionfly.
caudad Toward the tail, or toward the posterior end of the body.
caudal Pertaining to the tail or posterior end of the body.
caudal filament A threadlike process at the posterior end of the abdomen.
cell A space in the wing membrane partly (an open celll or completely (a closed celll surrounded by veins.
cell (of the wing) A thin, membranous area surrounded by veins.
Cephalothorax. head + thorax
cercus (pl., cerci) An antennalike sensory appendage arising from the posterior end of the abdomen.
cell. The area between the veins of a wing; it is closed when completely surrounded by veins, otherwise it is open.
cenchrus (pl., cenchri). In Symphyta, a paired circular, or oval structure on the sublateral portion of the metascutum.
Roughened pad on the metanotum of sawflies (Symphyta) serving to hold the wings in place when folded over
cephalad Toward the head or anterior end.
cephalic On or attached to the head; anterior.
cephalothorax A body region consisting of head and thoracic segments (Crustacea and Arachnida).
cercus (pl., cerci; adj., cercal). A paired, posterior, sensory appendage of the last (morphological 1/10th) abdominal
tergum, which usually bears sevgeral setae. With a reduction of the apical segments of the metasoma, the cerci
often seem to be on a more anterior segment.
cercus (pl., cerci) One of a pair of appendages at the posterior end of the abdomen.
cervical Pertaining to the neck or cervix.
cervical sclerite A sclerite located in the lateral part of the cervix, between the head and the prothorax.
cervix The largely membranous neck region of an insect, between head and thorax.
chaetotaxy The arrangement and nomenclature of the bristles on the exoskeleton (Diptera).
cheek The lateral part of the head between the compound eye and the mouth (see genai
chela (pl., chelae; adj., chelate). In Dryinidae, the modified tarsus in which the apical tarsomere forms a clasping
structure with its opposable tarsal claw; a pincer.
chelate Pincerlike, having two opposable claws.
chelicera (pl., chelicerae) One of the major elements in the mouthparts of spiders and related arthropods; not jawlike,
but in the form of fangs, pincers, or piercing organs.
chelicera (pl., chelicerae) One of the anterior pair of appendages in arachnids.
cheliped A leg terminating in an enlarged pincerlike structure (Crustacea).
chemoreceptor A sensillum capable of detecting chemicals (by olfaction and/or gustationi.
chemoreceptor A sense organ modified for the reception of chemical stimuli.
chemotaxis Orientarion with respect to a chemical gradient.
chitin A nitrogenous polysaccharide formed primarily of units of N‑acetyl glucosamine, occurring in the cuticle of arthropods. The tough, insoluble polysaccharide making up a major part of the insect procuticle
chordotonal organ A sense organ, the cellular elements of which form an elongate structure attached at both ends to
the body wall.
chordotonal organ An elongate sense organ attached to the inner surface of the body wall and sensitive to stretching
and to vibrations .
choriogenesis Formation of the shell (chorion) of the egg.
chorion The outer shell of an arthropod egg.
chrysalis (pl., chrysalids or chrysalides) The pupa of a butterfly.
cibarium A preoral cavity enclosed by the labrum anterior, the hypopharynx or labium posteriorly, and the mandibles
and maxillae laterally.
circadian rhythm An endogenous rhythm involving a response at about 24‑hour intervals .
circulatory virus A virus that circulates within the body of an insect before being introduced into a new host.
cleptoparasite A l'thief parasite," one that consumes the food stored by another insect in a nest.
climatic release Release of climatic restraints, such as a period of favorable weather or entry into a favorable region,
resulting in population increase.
clypeus A sclerite on the front of ~ne head, above the labrum.
coevolution An evolutionary change in a trait of individuals of one population in response to a trait of individuals of
a second population, followed by an evolutionary response of the second population to a change in the first.
colleterial gland An accessory gland of the female that produces the ootheca.
communication The production of a signal by an individual that influences the behavior of another individual and that
is mutually beneficial.
companionate planting The intercropping of certain repellent plants with crop plants.
circumesophageal connective A nerve connecting the tritocerebral lobes of the brain with the subesophageal ganglion.
class A subdivision of a phylum or subphylum, containing a group of related orders.
claval lobe. The posterior portion of a wing behind the claval fold and in front of the jugal fold, when present (also see
claval fold. The furrow on the forewing jsut anterior to, and aprallel with, vein 1A, and extending to the claval notch
on the wing margin.
claval suture The suture of the front wing separating the clavus from the corium (Hemiptera).
claval vein A vein in the clavus (Hemiptera, Homoptera).
clavate Clublike, or enlarged at the tip; clavate antennae.
clavus The oblong or triangular anal portion of the front wing (Hemiptera and Homoptera)
claw tuft A dense tuft of hairs below the claws (spiders)
cleft Split or forked.
cleptoparasite A parasite that feeds on food stored for the host larvae.
closed cell A wing cell bounded on all sides by veins.
closed coxal cavity One bounded posteriorly by a sclerite of the same thoracic segment of front coxal cavities, (Co
leoptera) or one completely surrounded by sternal sclerites and not touched by any pleural sclerites of middle
coxal cavities (Coleoptera).
club. The enlarged apical flagellar segment or segments of an antenna (also see funicle).
clubbed With the distal part ior segmentsl enlarged; clubbed antennae.
clypeus (adj. clypeal). The medial sclerite of the head immediately above the labrum; often defined dorsally and
laterally by the epistomal groove. A sclerite on the lower part of the face, between the frons and the labium.
coarctate larva A larva somewhat similar to a dipterous puparium, in which the skin of the preceding instar is not
completely shed but remains attached to the caudal end of the body; the sixth instar of a blister beetle, also
called a pseudopupa.
coarctate pupa A pupa enclosed in a hardened shell formed by the last larval skin (Diptera).
cocoon A silken case inside which the pupa is formed.
collophore A tubelike structure located on the ventral side of the first abdominal segment of Collembola.
collum The tergite of the first segment (Diplopoda).
colon The large intestine; that part of the hindgut between the ileum and the rectum.
colulus A slender pointed structure Iying just anterior to the spinnerets (spiders1
commensalism A living together of two or more species, none of which is injured thereby and at least one of which
commissure A structure (trachea or nervel that connects the left and right sides of a segment.
common oviduct The median tube of the female internal genitalia leading from the lateral oviducts to the gonopore.
competitive exclusion principle The concept that two species cannot long coexist if they have identical niches.
complete metamorphosis Striking changes between larva and adult, with an intervening pupal stage.
conditioning See Associative learning.
contest competition Competition involving aggressive interactions between individuals.
coprophagous Feeding on fecal material.
cornicle One of a pair of tubelike processes on the abdomen of aphids, secretes an allomone and an alarm pheromone.
cornicles. dorsal tubular structures on posterior abdomen
corpus allatum (pl., corpora allata) A small endocrine gland situated behind the brain, the source of juvenile hormone.
corpus cardiacum (pl., corpora cardiaca) A small organ of nervous origin just behind the brain, associated with
storage and release of PTTH and other hormones.
corpus pedunculatum (pl., corpora pedunculata) See Mushroom body.
compound eye An eye composed of many individual elements or ommatidia, each of which is represented externally
by a facet; the external surface of such an eye consists of circular facets that are very close together or of facets
that are in contact and more or less hexagonal in shape.
compressed. Flattened from side to side (higher than wide).
concave. Pertaining to a linear structure, margin, or surface that is curved inward (cf. convex).
concave vein A vein protruding from the lower surface of the wing.
condyle. A knoblike process forming an articulation.
connate Fused together or immovably united.
connective A structure (such as a trachea or nervel that runs from one segment to another.
contiguous Touching each other.
convergent Becoming closer distally.
convex vein A vein protruding from the upper surface of the wing.
convex vein A vein protruding from the upper surface of the wing.
corbicula (pl., corbiculae) A smooth area on the outer surface of the hind tibia, bordered on each side by a fringe of
long curved hairs, which serves as a pollen basket (beesl.
convex. Pertaining to a linear structure, margin, or surface that is curved outward (cf. concave).
corbicula (pl., corbiculae). In Apiformes, the concave, smooth region of the metatibia that is margined by a fringe of
setae arising from the margins; it forms a pollen basket. A smooth area on the outer surface of the hind tibia,
bordered on each side by a fringe of long curved hairs, which serves as a pollen basket (beesl.
corium The elongate, usually thickened, basal portion of the front wing (Hemiptera).
cornea The cuticular part of an eye.
cornicle One of a pair of dorsal tubular structures on the posterior part of the abdomen (aphids).
cornicle One of a pair of dorsal tubular structures on the posterior part of the abdomen (aphids).
corniculi (sing., corniculus) see urogomphi.
coronal suture A longitudinal suture along the midline of the vertex, between the compound eyes.
corpus allatum (pl., corpora allata) One of a pair of small structures immediately behind the brain, involved in
secretion of juvenile hormone.
costa A longitudinal wing vein usually forming the anterior margin of the wing; a sclerotized ridge in the cuticle.
costal area The portion of the wing immediately behind the anterior margin.
costal cell The wing space between the costa and the subcosta.
costal break A point on the costa where the sclerotization is weak or lacking or the vein appears to be broken (Diptera)
costal area The portion of the wing immediately behind the anterior margin.
costal notch. The excision of the wing margin between the apex of the costal vein and the base of the stigma.
coxa (pl., coxae; adj., coxal). The first segment of a leg, between the body and the trochanter. The basal segment of
the leg. The most basal segment of the insect leg, articulating with the thorax.
coxopleurite See catapleurite.
coxopodite The basal segment of an arthropod appendage.
coxosternum A sclerite representing the fusion of the sternum and the coxopodites of a segment.
crawler The active first instar of a scale insect.
cremaster A spinelike or hooked process at the posterior end of the pupa, often used for attachment (Lepidoptera).
crenulate Wavy, or with small scallops.
cribellum A sievelike structure Iying just anterior to the spinnerets (spiders).
crochets lpronounced croshays) Hooked spines at the tip of the prolegs of lepidopterous larvae.
crop An expansible part of the foregut that holds food until it can be passed into the midgut. The dilated posterior
portion of the foregut, just behind the esophagus.
crypsis Close resemblance of an animal to its physical or biotic background (also called protective coloration).
cross vein A vein connecting adjacent longitudinal veins.
cruciate Crossing; shaped
cryptonephridia Malpighian tubules that are closely associated with the hind gut and surrounded by a membrane, thus
separating this complex from the rest of the hemocoel.
ctenidium (pl., ctenidia) A row of stout bristles like the teeth of a comb.
cubito‑anal cross vein A cross vein between the cubitus and an anal vein.
cubitus The longitudinal vein immediately posterior to the media.
cultural control Modification of the environment‑‑for example, by tillage‑‑to make it less attractive to pests.
cuneus. Trriangular apical part of thickened portion of wing
cuticle The noncellular outer portion of the integument.
cuticulin The tough, insoluble substance making up the outer surface of the epicuticle, containing cross‑linked lipid
and protein molecules.
cytoplasmic polyhedrosis virus (CPV) A virus that develops in the cytoplasm of host cells, chiefly in the midgut.
Darwinian fitness differential reproduction, in terms of the number of genes an individual passes to the next
depressed. Flattened from top to bottom (wider than high).
density‑dependent factor A factor that causes a level of mortality that varies with the number of individuals in the
deutocerebrum The middle section of the brain, which innervates the antennae.
diapause A state of arrested behavior, growth, and development that occurs at one stage in the life cycle.
digitus. Pad-like lobe of male genitalia
direct pest A pest insect that attacks a part of a plant that is harvested, as contrasted to an indirect pest.
dorsal Referring to the upper surface (back) of an animal.
dorsal diaphragm A muscular shcet underlying the heart which assists in the flow of blood.
dorsal longitudinal muscles Muscles running longitudinally, dorsally in insect segments, in the thorax powering the
downstroke of the wings of most insects.
dorsoventral muscles Muscles inserting on the dorsum of the thorax and originating ventrally, powering the upstroke
of the wings of most insects.
dorsum The upper surface (back) of an animal .
Dufour's gland An exocrine gland on the ventral, posterior part of the abdomen of female Hymenoptera, the source
of pheromones serving diverse functions.
disc (adj., discal). The central surface of any structure.
dorsal diaphragm An incomplete wall of muscle separating the area around the dorsal blood vessel (the pericardial
sinus) from the rest of the hemocoel.
dorsocentral bristles A longitudinal row of bristles on the mesonotum, just laterad of the acrostichal bristles (Diptera).
dorsolateral At the top and to the side.
dorsomesal At the top and along the midline.
dorsoscutellar bristles A pair of bristles on the dorsal portion of the scutellum, one on each side of the midline
dorsoventral From top to bottom, or from the upper to the lower side.
dorsum The back or top (dorsal) side.
Dyar's rule The increase in width of the larval head capsule by a factor of 1.2‑1.4 from one molt to the next.
ecdysis Splitting and casting off of the old cuticle, the major event in molting.
ecdysone A molting hormone, secreted by the prothoracic glands.
eclosion Hatching of the egg, or emergence of the adult insect at the terminal molt.
ecological homolog One of two or more species having most niche parameters in common .
economic injury level (EIL) The level of damage to a crop that is equal in value to the cost of suppressive measures.
economic threshold (ET) The level of damage by a pest that serves to wam the agriculturalist of impending problems.
ecosystem A biological community considered in relation to its physical environment.
egg‑development neurosecretory hormone (EdNH) A product of the brain neurosecretory cells that stimulates
vitellogenesis in the female mosouito.
ejaculatory duct A median duct that carries the sperm from the intemal reproductive system to the exterior.
elytra. Thickened front wings (eg. , Coleoptera)
elytron (pl., elytra) The hardened front wing of a beetle.
emarginate. Notched; with an obtuse, rounded, or quadrate section cut out of a margin.
encapsulation The enclosure of a parasitoid larva within the blood of the host by a layer of hemocytes.
endocrine gland A gland that discharges its products (hormones) to the inside (as contrasted to an exocrine gland).
endocuticle The inner zone of the procuticle, softer and lighter in color than the exocuticle.
endogenous activity Nervous discharges that arise spontaneously, in the absence of stimulation .
endodterygote An insect that develops through the immature stages as a larva with wings retained internally as
endodont mandible. A mandible with the teeth facing inward so that when the mandibles are closed their tips point
toward each other's base (cf., exodont).
entomophagous Feeding on insects.
entomopox virus A virus that multiplies in the cell cytoplasm of fat body and blood cells in a variety of insects.
epicuticle The outer zone of the insect cuticle, rich in lipid and protein and lacking chitin.
epidermis The single outer cell layer of the body, which secretes the cuticle.
epimorphosis A type of development in which the insect emerges from the egg with its full complement of body
segments (opposite of anamorphosis).
equilibrium position (EP) In insect bioeconomics, the average density of a potential pest on a specific crop.
esophagus A tubular portion of the foregut, behind the pharynx.
epicnemial carina. The ridge on the mesopleuron that somewhat parallels the anterior margin of the mesepisternum
and that delineates the posterior margin of the epicnemium.
epicnemium (adj., epicnemial). The anterior portion of the mesopleuron delimited posteriorly by the epicnemial carina
(also see prepectus).
epimeron (pl., epimera; adj., epimeral). The portion of a pleuron posterior to the pleural groove (cf. episternum).
epipygium. In Chalcidoidea, a small, somewhat sclerotized, fingernail-like flap attached to the last metasomal tergum
between the cerci.
episternal groove. A groove on the mesopleuron, extending ventrally from a pit under the base of the forewing and,
when complete, reaching the anteroventral margin of the mesothorax.
episternum (pl., episterna; adj., episternal). The portion of a pleuron anterior to the pleural groove (cf. epimeron).
epistomal groove. A groove defining the lateral and dorsal margin of the clypeus.
epomia (pl., epomiae). In Ichneumonoidea, an oblique ridge crossing the transverse furrow on the side of the
eusociality A type of social behavior involving overlap of generations, cooperative brood care, and a caste system in
which many colony members are sterile.
exocrine gland A gland that discharges its products to the outside (as contrasted to an endocrine gland).
exocuticle The outer portion of the procuticle, generally harder and darker than the inner portion (endocuticle).
exodont. Extended outwards
exodont mandible. A mandible with the teeth facing outward so that when the mandibles are closed their tips point
anteriorly or away from each other (cf. endodont).
exopterygote An insect that retains its wing pads externally through its immature stages.
exoskeleton A skeleton extemal to the remainder of the body, the muscles attaching to its inner surface.
extrinsic Having its origin outside the limits of an organ with which it is associated.
face (adj., facial). In Parasitica, the anterior surface of the head between the eyes from the ventral margin of the toruli
to the oral cavity, excluding the clypeus; in Symphyta and Aculeata, anterior surface of the head between the
eyes from the ocelli to the oral cavity, including the clypeus.
face The front of the head, below the frontal suture (Diptera).
facet The external surface of an individual compound‑eye unit or ommatidium. falx An interantennal suture with
internal sclerotized margins connecting the upper ends of the antennal fossae ISiphonaptera).
facial fovea. In Apoidea, a depressed, often finely densely pubescent area along the inner orbit of a compound eye.
family A subdivision of an order, suborder, or superfamily, containing a group of related genera, tribes, or subfamilies.
Family names of animals end in ndae.
farnesene An alarm pheromone of aphids, secreted from the cornicles.
fat body Accumulation of large cells in the hemocoel that store metabolites and are centers of intermediary metabolism.
femur (pl., femora) The third segment of the insect leg, beyond the trochanter and before the tibia.
fibril The contractile unit of a muscle cell (fiber).
filter chamber A modification of the gut of many Homoptera (such as aphids), permitting n uch water and some
carbohydrates to b~pass the midgut.
filter feeder An insect that seines particles from water by means of brushes or webs.
fixed action pattern A segment of behavior performed in a stereotyped, species‑specific manner.
flagellum The outermost part of the antenna, beyond the scape and pedicel, usually divided into many subsegments
follicle A tubule of the testis in which sperm are produced.
foulbrood A bacterial disease of honey bee larvae and pupae.
founder effect Speciation resulting from the establishment of a small population in an entirely new area and the
subsequent divergence of the resulting population from the parent stock.
frontalin A sex attractant pheromone of male bark beetles.
fastigium The anterior dorsal surface of the vertex (grasshoppers). fat body An amorphous organ involved in
intermediate metabolism, storage, and storage excretion.
feces Excrement, the material passed from the alimentary tract through the anus.
felt line A narrow longitudinal band of relatively dense, closely appressed hairs of Mutillidae).
felt line. In Mutillidae adn Bradynobaenidae, a longitudinal line of flattened setae and secretory pores laterally on
metasomal tergum 2.
femur (pl., femora; adj., femoral). The 3rd segment of a leg, between the trochanter and tibia.
fiament A slender threadlike structure. file A filelike ridge on the ventral side of the tegmen, near the base; a part of the stridulating mechanism in crickets and long‑horned grasshoppers.
fibula A more or less triangular jugal lobe in the front wing that serves as a means of uniting the front and hind wings
filiform Hairlike or threadlike, filiform antenna.
filter chamber A modification of the alimentary canal in Homoptera in which the anterior portion of the midgut is
closely associated with the hindgut.
flabellate With fanlike processes or projections; flabellate antenna.
flabellum (pl., flabella) A fanlike or leaflike process (Hymenoptera.
flabellum (pl., flabella). In Apiformes, a small thin plate of the apex of the glossa.
flagellomere. A segment-like subdivision of the flagellum; it is numbered consecutively from the base of the flagellum.
One of the subsegments of the flagellum.
flagellum (pl., flagella; adj., flagellar). The 3rd primary division or segment of the antenna; it articulates with the
pedicel basally and almost always is subdivided into segments (= flagellomeres). A whiplike structure that part
of the antenna beyond the second segment.
flexor muscle A muscle that decreases the angle between two segments of an appendage.
follicle A minute cavity, sac, or tube.
follicular epithelium Layer of epithelial cells surrounding the oocyte.
fontanelle A small, depressed, pale spot on the front of the head between the eyes (lsoptera).
foramen (pl., foramina). A hole in the body wall through which vessels or nerves pass. The foramen magnum is the
central hole in the back of the head; the propodeal foramen is the hole in the posterior area of the propodeum.
foramen magnum The opening on the posterior side of the head, through which pass the internal structures that extend
from the head to the thorax; also occipital foramen.
foregut The anterior portion of the alimentary tract, from the mouth to the midgut.
fossorial Fitted for or with the habit of digging. frass Plant fragments made by a wood‑boring insect, usually mixed
frenulum A bristle or group of bristles arising at the humeral angle of the hind wing Lepidoptera).
frenum (pl., frena; adj., frenal). In Chalcidoidea, the transverse line on the scutellum that delineates a posterior portion
of the scutellum, the frenal area.
frons. The area of the head bvetween the ventral margin of the toruli and the anterior margin of the median ocellus (this
is not equivalent to the true frons of larvae). The head sclerite bounded by the frontal lor frontogenali and
epistomal sulci and including the median ocellus.
front That portion of the head between the antennae, eyes, and ocelli; the frons.
frontal bristles Bristles above the antennae, away from the edge of the compound eye (Diptera).
frontal carina A longitudinal ridge or pair of ridges on the frons between (and sometimes partly covering) the toruli.
frontal lunule A small crescent‑shaped sclerite located just above the base of the antennae and below the frontal suture
frontal suture One of two sutures arising at the anterior end of the coronal suture and extending ventrad toward the
epistomal sulcus; a suture shaped like an inverted U, with the base of the U crossing the face above the bases
of the antennae and the arms of the U extending downward on each side of the face (Diptera; actually a ptilinal
frontal vitta An area on the head between the antennae and the ocelli (Diptera).
fronto‑orbital bristles Bristles on the front next to the compound eyes (Diptera).
frontogenal suture (or sulcusi) A more or less vertical suture on the front of the head, between the frons and the gena.
funicle (adj., funicular). A group of flagellomeres between the pedicel and the club.
funiculus (or funicle) The antennal segments between the scape and the club ICole6pteral, or between the pedicel and club IHymen6pteral. furca A fork or forked structure; a forked apodeme arising from a thoracic sternum.
furcula The forked springing apparatus of the Collembola.
galea The outer lobe of the maxilla, borne by the stipes.
galea An apical lobe of the maxilla of an insect.
galea (pl., galeae). The outer apical lobe of the maxilla that articulates basally with the stipes.
gall An abnormal growth on a plant, produced by stimulation of an insect or other organism and housing that organism.
ganglion (pl., ganglia) A mass of nervous tissue, the basic anatomical unit of the central nervous system.
gastric caecum (pl., caeca) A fingerlike, anterior extension of the midgut that sen~es a function in food absorption.
genitalia Structures associated w ith the release of sperm or eggs.
gall An abnormal growth of plant tissues, caused by the stimulus of an animal or another plant.
ganglion (pl., ganglial A knotlike enlargement of a nerve, containing a coordinating mass of nerve cells.
gaster The rounded part of the abdomen posterior to the nodelike segment or segments IHymen6ptera Ap6crital .
gastric caecum Caecum located at the anterior portion of the midgut.
gastrocoelus-thyridium (pl., gastrocoeli). In Ichneumonidae, the usually transverse impression anterolaterally on
metasomal tergum 2. The gastrocoelus includes the thyridium, which is the surface area with specialized
sculpture, whereas the gastrocoelus is the impression itself.
gastrocoelus-thyridium (pl. gastrocoeli). In Ichneumonidae, the usually transverse impression anterolaterally on
metasomal tergum 2. The gastrocoelus includes the thyridium, which is the surface area with specialized
sculpture, while the gastrocoelus is the impression iteself.galea (pl., galeae). The outer apical lobe of the
maxilla, articulated basally with the stipes.
gena (pl., genae; adj., genal). The cheek; the lateral part of the head between the compound eye and, when present,
the occipital carina; otherwise, the lower (in hypognathous head) or anterior (in prognathous head) part of the
back of the head between the compound eye and the occiput. The part of the head on each side below and
behind the compound eyes, between the frontal and occipital sulci.
genal comb A row of strong spines borne on the anteroventral border of the head (Siphonaptera).
gneration From any given stage in the life cycle to the same stage in the offspring.
geniculate Elbowed, or abruptly bent; geniculate antenna.
genital chamber See bursa copulatnx.
genitalia The sexual organs and associated structures; the external sexual organs.
genovertical plate An area on the head above the antenna and next to the compound eye (Diptera; also called orbital
genus (pl., genera) A group of closely related species; the first name in a binomial or trinomial scientific name. Names
of genera are latinized, capitalized, and when printed are italicized.
germ band A thickening of the klastoderm that produces the embryo.
germarium An area at the tip of the sperm follicles or ovarioles where sperm or egg formation is initiated. Apical
portion of the ovariole or sperm follicle.
giant axon A large‑diameter axon of an interneuron that traverses several body segments and conducts messages
glial cell A cell surrounding the axon of a neuron.
gill Evagination of the body wall or hindgut, functioning in gaseous exchanges in an aquatic animal.
gonopore The external opening of the reproductive tract.
granulosis virus (GV) A virus that multi plies in both the nucleus and cytoplasm of host cells, usually in the fat body.
glabrous Smooth, without hairs.
globose, globular Spherical or nearly so.
glossa (pl., glossae). The paired, fused, median lobe of the labium articulated basally with the prementum.
glossa (pl, glossaei) One of a pair of lobes at the apex of the labium between the paraglossae (in bees).
glymma (pl., glymmae). In Ichneumonidae, the paired groove or pit on the side of metasomal segment 1 between its
base and the spiracle; it is nearly always present when sternum 1 is free from tergum 1 but absent when tergum
1 and sternum 1 are fused.
gnathochilarium A platelike mouthpart structure in the Diplopoda, representing the fused maxillae and labium.
gonangulum A sclerite of the female external genitalia derived from the second gonocoxa, connecting the second
gonocoxa, ninth tergum, and first gonapophysis.
gonapophysis (pl., gonapophyses) A mesal posterior process of a gonopod, in the female forming the ovipositor; first
or second valvula.
gonocoxa A modified coxa that forms a part of the external genitalia ( = valviferi.
gonoplacs Lateral sheaths enveloping the ovipositor in pterygotes ( = third valvulael.
gonopod A modified leg that forms a part of the external genitalia.
gonopore The external opening of the reproductive organs.
gonostylus Stylus of a genital segment labdominal segment 8 or 91.
gregarious Living in groups.
grub A scarabaeiform larva; a thick‑bodied larva with a well‑developed head and thoracic legs, without abdominal
prolegs, and usually sluggish.
groove. A linear impression on a sclerite (also see suture).
gula A sclerite on the ventral side of the head between the labium and the foramen magnum.
gular sutures Longitudinal sutures, one on each side of the gula.
gustation Taste detection of chemicals in liquid.
gynandromorph An abnormal individual containing structure characteristics of both sexes (usually male on one side
and female on the other)
habituation Leatning not to respond to a stimulus that provides no reward or punishment .
hair pencils Tufts of fine setae serving to dust pheromone‑coated particles onto a memher of the opposite sex.
haltere A modified hind wing of a fly (Diptera), acting to maintain flight stability.
haplodiploidy A type of parthenogenesis in which males are produced from unfertilized eggs and are therefore haploid,
while the females are diploid.
haltere (pl, halteres) A small knobbed structure on each side of the metathorax, formed from a modified hind wing
hamuli jsing., hamulusl Minute hooks; a series of minute hooks on the anterior margin of the hind wing, with which
the front and hind wings are attached together lHymenopterai .
haustellate Formed for sucking, the mandibles not fitted for chewing (or absent).
haustellum A part of the beak (Diptera).
head The anterior body region, which bears the eyes, antennae, and mouthparts.
head. The principal anterior division of the body; it bears the mouthparts and antennae.
heart A muscular tube extending dorsally and longitudinally through the insect abdomen, continuous with the aorta,
serving in circulation of blood. The posterior pulsatile portion of the dorsal blood vessel
hematophagous Feeding on blood.
hemelytron (pl., hemelytra) The forewing of an insect that is sclerotized basally but membranous apically (literally,
half an elytron; applied chiefly to Hemiptera).
hemimetabolous Having incomplete or simple metamorphosis, that is, showing gradual change from molt to molt, with
externally developing wing pads. (Odonata, Ephemeroptera, Plecoptera), with nymphs aquatic.
hemocoel The blood‑filled body cavity.
hemocyte A blood cell.
hemocytes Blood cells.
hemolymph The "blood" of insects, combining functions of the lymph and blood of vertebrates (other than respiration).
The blood of arthropods.
herbivorous Feeding on plants.
hermaphroditic Possessing both male and female sex organs.
hertz Cycles per second (Hz).
heterodynamic life cycle A life cycle in which there is a period of dormancy.
heterogamy Alternation of bisexual with parthenogenetic reproduction.
heteromerous The three pairs of tarsi differing in the number of segments lColeoptera, for example, with a tarsal
formula of 5‑5‑41.
hibernation Dormancy during the winter.
hindgut The posterior portion of the alimentary tract, between the midgut and the anus.
holocrine secretion Release of enzymes by disruption of the entire cell.
holometabolous Having complete metamorphosis, passing through egg, larval, pupal, and adult stages.
homeostasis Maintenance of a functionally steady state in the body, in the colony of social insects, or in an ecos~stem.
holoptic The eyes contiguous above lDipterai.
homodynamic lile cycle A life cycle in which there is continuous development, without a period of dormancy.
homology Similarity in structure resulting from having had a common evolutionary origin.
honeydew The liquid excretions of sucking insects (Homoptera), consisting largely of water and sugars.
hormone An intemal chemical signalproluced by an endocrine gland and carried to the tissues by the hemolymph.
horns. Found around antennae in Chalcididae
host race A population of a species that shows a genetically determined preference for a particular host plant or animal
hydrostatic skeleton Maintenance of body form by the pressure exerted by muscles on a fluid‑filled body cavity, most
important in soft‑bodied larvae.
hypermetamorphosis A type of development in which there are two or more quite distinct larval forms sequentially.
hyperparasitoid An insect that is a parasitoid of a parasitoid.
hypopharynx A tonguelike structure in the buccal cavity, associated with the labium.
homonym One and the same name for two or more different things (taxa)
honeydew Liquid discharged from the anus of certain Homoptera.
hornworm A caterpillar (larva of Sphingidae) with a dorsal spine or horn on the last abdominal segment.
horny Thickened or hardened.
host The organism in or on which a parasite lives; the plant on which an insect feeds.
humeral Pertaining to the shoulder; located in the anterior basal portion of the wing.
humeral angle The basal anterior angle or portion of the wing.
humeral bristles The bristles on the humeral callus (Diptera).
humeral callus One of the anterior lateral angles of the thoracic notum, usually more or less rounded (Diptera).
humeral cross vein A cross vein in the humeral portion of the wing, between the costa and subcosta.
humeral plate The anterior sclerite of the wing at the base of vein C.
humeral suture The mesopleural suture (Odonata).
humeral vein A branch of the subcosta that serves to strengthen the humeral angle of the wing (Neuroptera,
humerus (pl., humeri) The shoulder; the posterolateral angles of the pronotum (Hemiptera1
humulus (pl., hamuli). One of a series of small bristle-like hook on the anterior martin of the hind wing; in some
groups there may be a basal and an apical series of hamuli.
hyaline Like glass, transparent, colorless.
hypermetamorphosis A type of complete metamorphosis in which the different larval instars represent two or more
different types of larvae.
hyperparasite A parasite whose host is another parasite.
hypodermis See epidermis.
hypognathous. With the head somewhat at a right angle to the plane of the body (vertical), so the mouthparts are
directed ventrally (cf. prognathous).
hypopharynx A median mouthpart structure anterior to the labium; the ducts from the salivary glands are usually
associated with the hypopharynx, and in some sucking insects the hypopharynx is the mouthpart structure
containing the salivary channel.
hypopleural bristles A more or less vertical row of bristles on the hypopleuron, usually directly above the hind coxac
hypopleuron (pl, hypopleura) The lower part of the mesepimeron; a sclerite on the thorax located just above the hind
hypopygium (adj., hypopygial). The last visible sternum of the abdomen.
hypostigmatic cell The cell immediately behind the point of fusion of Sc and R (Neuroptera, Myrmeleontoidea).
hypostomal bridge The sclerotized posterior part of the head that sometimes separates the foramen magnum from the
oral cavity (the bridge may sometimes be formed by the median fusion of the postgena or gena and is then
called the postgenal or genal bridge). Mesal extension of the hypostomae on each side to meet below the foramen magnum.
hypostomal carina. The ridge on the back of the head along the oral cavity that normally delimits the hypostoma from
the postgena and occiput.
Hz Hertz (cycles per second).
ileum The anterior part of the hindgut, preceding the rectum.
imaginal disc A group of cells set aside in the embryo and maintained through the larval stage as a center of
development of adult structures .
imago The terminal instar, or adult.
inclusion body A protein crystal that encloses an insect virus.
inclusive fitness Net genetic representation of an individual in succeeding generations, through personal reproduction
and that of individuals bearing identical genes.
incomplete metamorphosis Slight changes from molt to molt until wings and genitalia are fully formed in the adult.
indirect pest A pest insect that feeds on a part of the plant that is not marketed.
insect growth regulator (IGR) A substance produced by a plant that mimics or antagonizes an insect hormone.
insight learning The ability to combine leamed behavior from diverse experiences to solve a problem.
instar The stage of an insect's development between molts.
instinct Behavior performed without previous experience and without interaction with other members of the species.
integrated pest management (IPM) An approach to the control of pests (insects, diseases, weeds) in which all
available techniques are evaluated and integrated into a unified program.
interference competition Competition in which individuals are prevented from feeding, mating, or laying eggs as a
result of the presence of other individuals.
interneuron A nerve cell located within the central nervous system and serving to connect other neurons.
intersexual selection Natural selection involving choices between the sexes, often on the basis of courtship displays.
intrasexual selection Natural selection involving competition among members of one sex of a species, usually for
intrinsic Located entirely within an organ (as contrasted to extrinsic).
ipsenol An aggregation pheromone of bark beetles of the genus Ips.
Johnston's organ A sense organ similar to a chordotonal organ, located in the second antennal segment of most insects;
this organ functions in sound perception in some Diptera. joint An articulation of two successive segments or
parts. An organ in the pedicel of the antenna, consisting of a cluster of chordotonal sensilla.
jugal lobe A lobe at the base of the wing, on the posterior side, proximad of the vannal lobe (Hymenoptera). The
posterior area of the wing behind vein 1A and set off from more anterior areas by a slight fold (jugal fold) on
the wing and by a notch on the wing margin (also see claval lobe).
jugal vein The most posterior of the major longitudinal vein systems according to Kukalova‑Peck. jugum A lobelike
process at the base of the front wing, which overlaps the hind wing (Lepidoptera); a sclerite in the head
(Hemiptera and Homoptera).
juvabione An insect growth regulator occurring in certain trees and causing abnormal development of insects feeding
on the tree.
juvenile hormone (JH) A hormone secreted by the corpora allata that maintains juvenile features in immature insects
and controls certain aspects of adult physiology and behavior.
kairomone An interspecific chemical messenger that benefits the receiver but not the emitter.
katepleurite See catapleunte. keeled With an elevated ridge or carina. kHz Kilohertz Ikilocycles per secondl.
kin selection Natural selection that involves inclusive fitness.
kinesis An undirected movement in which the speed of movement or the frequency of tuming depends on the intensity
of stimulation .
K‑strategist A species characterized by a low reproductive rate, increased survival mechanisms, minor tendency to
disperse, and often a relatively large body size (as compared to an r‑strategist).
labellum (p. labellae). The expanded tip of the labium IDiptera; Iabial or pertaining to the labium.
Iabial gland Exocrine organ opening on or at the base of the labium, usually functioning as salivary or silk gland.
Iabial suture The suture on the labium between the postmentum and prementum.
Iabial palp One of a pair of small feelerlike structureS arising from the labium.
labium One of the mouthpart structures, the lower lip.
Iabrum The upper lip, Iying just below the clypeus.
Iabrum‑epipharynx A mouthpart representing the labrum and epipharynx.
Iacinia ipl., laciniael The inner lobe of the maxilla, borne by the stipes.
Iamella (pl., lamellae) A leaflike plate.
Iamellate With platelike structures or segments; lamellate antennae.
Iamina In the cuticle, a layer of cuticle with chitin microfibrils oriented in the same direction.
Iamina lingualis (pl., laminae linguales) One of two median distal plates in the millipede gnathochilarium.
Ianceolate Spear‑shaped, tapering at each end.
lanule. Crescent-shaped sclerite above base of antennae
Iarva (pl., larvae) The immature stage, between egg and pupa, of an insect having complete metamorphosis; the
six‑legged first instar of Acari; an immature stage differing radically from the adult.
Iarviform Shaped like a larva.
Iaterad Toward the side, away from the midline of the body.
Iateral Of or pertaining to the side (that is, the right or left sidel.
Iateral oviduct A tube in the female internal genitalia connecting the ovaries and the common oviduct.
Iaterotergite A tergal sclerite located laterally or dorsolaterally.
Iateroventral To the side laway from the midline of the body) and below.
Ieaf miner An insect that lives in and feeds upon the leaf cells between the upper and lower surfaces of a leaf.
Iigula The terminal lobe (or lobej of the labium, the glossae and paraglossae.
Iinear Linelike, long and very narrow.
Iongitudinal Lengthwise of the body or of an appendage.
Iooper A caterpillar that moves by looping its body, that is by placing the posterior part of the abdomen next to the
thorax and then extending the anterior part of the body forward; a measuringworm.
Iorum (pl., lora) The cheek; a sclerite on the side of the head of Hemiptera and Homoptera; the submentum in bees.
Iuminescent Producing light.
Iunule, frontal see frontal lunule.
labium The third set of mouthparts of insects (or underlip~, located behind the maxillae.
labrum A flaplike structure anterior to the mouthparts, kelow the clypeus.
labium (adj., labial). The posterior, medial appendage of the mouthparts between adn behind the maxillae, composed
of the submentum, emntum, prementum, glossa, paraglossa, and labial palpi.
labrum (adj., labral). The anterior, medial appendage of the mouthparts attached to the underside of, and often
concealed by, the clypeus.
lacina (pl., laciniae). The inner apical lobe of the maxilla, articulated to the stipes.
lamina (pl., laminae; adj., laminate). A thin plate or leaf-like process.
latent learning Conditioning in which the reward occurs some time following receipt of the stimulus.
life table A tabulation of the life stages of an insect with a cumulative record of mortality and survival.
light compass orientation Orientation in which a constant angle with a light source (usually the sun) is maintained.
laterotergite. The lateral part of an abdominal/metasomal tergum that is marked by a crease or groove, or is even
completely detached from the main dorsal part of the tergum (also see tergite, tergum).
locustol A primer pheromone of the desert locust that triggers development from the solitary to the gregarious form.
maggot A vermiform larva; a legless larva without a welldeveloped head capsule (Diptera).
malar space. The shortest distance between the base of the mandible and the margin of the compound eye.
Malpighian tubules Excretory tubes that arise near the anterior end of the hindgut and extend into the body cavity.
An excretory tubule, opening into the gut at the junction of the midgut and hindgut.
mandible Jaw; one of the anterior pair of paired mouthpart structures.
mandibulate With jaws fitted for chewing.
marginal cell A cell in the distal part of the wing bordering the costal margin (Diptera, Hymenoptera).
mandible (adj., mandibular). The paired, heavily sclerotized biting and chewing lateral appendage of the mouthparts
between the labrum and maxilla.
marginal vein A vein on or just within the wing margin; the vein forming the posterior side of the marginal cell
margined With a sharp or keellike lateral edge.
maxilla (pl., maxillae; adj., maxillary). The paired appendage of the mouthparts between the mandible and labium,
consisting of the cardo, stipes, lacinia, galea, and maxillary palpus.
maxillary Of or pertaining to the maxilla.
maxillary palp A small feelerlike structure arising from the maxilla.
maxilliped One of the appendages in Crustacea immediately posterior to the second maxillae.
mandible One of the most anterior pair of insect mouthparts, often jawlike and working from side to side.
maxilla One of a pair of mouthparts behind the mandibles and before the labium, bearing the maxillary palpi.
mechanoreceptor A sensillum sensitive to physical displacement .
media The longitudinal vein between the radius and cubitus.
medial (or median) Referring to the center, usually the midline, of an animal.
medial cross vein A cross vein connecting two branches of the media.
median In the middle; along the midline of the body.
medio‑cubital cross vein A cross vein connecting the media and cubitus.
membrane A thin film of tissue, usually transparent; that part of the wing surface between the veins; the thin apical
part of a hemelytron (Hemiptera).
membranous Like a membrane; thin and more or less transparent lwingsi; thin and pliable lcuticle1.
mental setae Setae on the mentum (Odonata).
mentum The distal part of the labium, which bears the palps and the ligula; a median, more or less triangular piece in
the millipede gnathochilarium.
mentum. A labial sclerite articulating basally with the submentum and apically with the prementum; often fused with
the latter and indistinguishable as a separate sclerite.
merocrine secretion Release of enzymes across the cell membrane, without destruction of the entire cell.
meroistic ovary An ovary possessing nurse cells that are connected to or accompany the oocytes.
meroistic ovariole Ovariole with nurse cells.
meropleuron. The lateral and ventral part of the mesothorax (also see mesosternum)
meropleuron (pl., meropleura) A sclerite consisting of the meron lbasal part1 of the coxa and the lower part of the
mes-, meso-. A Greek prefix meaning middle or mid; used with Latin, latinized, or Greek words to indicate the middle
(often 2nd) part of a structure.
mesad Toward the midline of the body. mesal At or near the midline of the body.
mesenteron The midgut, or middle portion of the alimentary tract.
mesepimeron (pl., mesepimera) The epimeron of the mesothorax.
mesepimeron. The posterior subdivision of the mesopleuron, usually small relative to the mesepisternum or almost
mesepisternal groove. A groove on the mesopleuron, extending ventrally from a pit under the base of the forewing
and, when complete, reaching the anteroventral margin of the mesothorax.
mesepisternum (pl., mesepisterna) The episternum of the mesothorax. The anterior subdivision of the mesopleuron,
usually comprising most of the mesopleuron.
mesinfraepisternum A ventral subdivision of the mesepisternum (Odonata).
meson The midline of the body, or an imaginary plane dividing the body into right and left halves.
Mesonotal suture. Dorsal sclerite of mesothorax
mesonotum The dorsal sclerite of the mesothorax.
mesothorax The middle segment of the insect thorax.
mesopleural bristles Bristles on the mesopleuron (Diptera).
mesopleuron (pl., mesopleura) The lateral sclerite~s1 of the mesothorax; the upper part of the episternum of the
mesoscutal lobe. The mesoscutum is usually divided by the notauli into a medial part and two lateral lobes (also see
mesoscutellar appendage. In Symphyta, the posterior subdivision of the mesoscutellum, usually crescent-shaped and
overhanging the postnotum of the mesothorax.
mesoscutellum The scutellum of the mesothorax, usually simply called the scutellum.
mesoscutellum. The middle region of the mesonotum or metanotum, behind the scutum. In Apocrita, only the
mesoscutellum is evident and is simply called the scutellum, while in Symphyta both the mesoscutellum and
metascutellum are present.
mesoscutum The scutum of the rnesothorax.
mesoscutum. The mesonotum excluding the scutellum; in groups with a transscutal articulation, the portion of the
mesonotum anterior to the articulation; the mesoscutum is usually divided by the notauli into a medial part and
two lateral lobes (also see scutum).
mesosoma (pl., mesosomata; adj., mesosomal). In Apocrita, the thorax plus the propoedum (cf. thorax). In Apocrita
IHymenoptera) the middle tagma of the body, composed of the three thoracic segments and the first true
abdominal segment Ithe propodeum).
mesosternum. The sternum of the mesothorax, usually invaginated and not visible, but sometimes incorrectly used as
a general term for the ventral surface of the mesothorax, such as when it is modified into a flattened plate with
posteriorly projecting lobes (also see mesopleuron). The sternum, or ventral sclerite, of the mesothorax.
mesothorax The middle or second segment of the thorax.
mesothorax. The 2nd and largest of the 3 primary subdivision of the thorax, bearing the middle pair of legs and, when
present, the forewings.
mesotrochantinal plate. The ventral part of the mesothorax inflected towards the metasternum beneath the base of the
mesocoxae; visible only by removing the mesocoxae.
met-, meta-. A Greek prefix meaning hind or posterior; used with Latin, latinized, or Greek words to indicate the
posterior (usually 3rd) part of a structure.
metamere A primary body segment lusually referring to the embryo).
metamorphosis A change in form during development.
metanotum The dorsal sclerite of the metathorax.
metanotum. The dorsal part of the metathorax.
metapleuron. The lateral and ventral part of the metathorax.
metapneustic. Only two spiracles are retained at the posterior end of the body.
metascutellum The scutellum of the metathorax.
metascutellum. In Symphyta, the middle region of the metanotum.
metasoma In Ap6crita (Hymenoptera) the posterior tagma of the body, comprised of all segments posterior to the
metasoma. (pl., metasomata; adj., metasomal). In Apocrita, the apparent abdomen, consisting of the abdomen
excluding the 1st segment or propodeum (cf. abdomen).
metasternum. The sternum of the metathorax, usually invaginated and not visible but sometimes used as a general term
for the ventral surface of the metathorax.
metatarsus (pl., metatarsi) The basal segment of the tarsus.
metathorax. The 3rd of the three primary subdivision of the thorax, bearing the hind pair of legs and, when present,
the hind wings. The most posterior of the three segments of the thorax.
metazonite The posterior portion of a mlllipede tergum when the tergum is divided by a transverse groove.
metepimeron (pl., metepimera) The epimeron of the metathorax.
metepimeron. The posterior subdivision of the metapleuron.
metepisternum (pl., metepisterna) The episternum of the metathorax.
metepisternum. The anterior subdivision of the metapleuron.
metinfraepisternum A ventral subdivision of the metepisternum (Odonata).
micropile A pore in the chorion through which sperm enter. A minute opening lor openings) in the chorion of an insect
egg, through which sperm enter the egg.
midgut The mesenteron, or middle portion of the alimentary tract.
migration A form of dispersal involving longdistance movements under at least partial control of the insects.
mimicry Presence of a pattem in a palatable species that closely resembles the pattem of an unpalatable species ( =
Batesian mimicry) (see also Mullerian mimicry).
millimeter 0.001 meter, or 0.03937 inch (about ~s inch).
minute Very small; an insect a few millimeters in length or less would be considered minute. molt A process of
shedding the exoskeleton; ecdysis; to shed the exoskeleton.
molting gland See prothoracic glands.
molting hormone (MH) See Ecdysone.
monoculture A uniform stand of one kind of crop plant.
monecious Possessing both male and female sex organs, hermaphroditic.
moniliform Beadlike, with rounded segments; moniliform antenna.
monocondylic A joint with a single point of articulation.
monophagous Feeding on a single plant or animal species.
morphology The science of form or structure.
motor neuron A neuron that forms a synapse with a muscle.
mouthparts. The appendages of the head used for feeding, including the labrum, hypopharynx, mandibles, maxillae,
Mullerian mimicry Presence of a similar aposematic pattem in unrelated, distasteful or poisonous species.
multivoltine Having several generations a year.
mushroom body A complex fiber tract in the anterior part of the brain, often suggesting the shape of a mushroom,
associated primarily with the integration of sensory information .
mutualism A living together of two species of organisms, with both species being benefited by the association.
mycetome A specialized internal organ that houses symbiotic microorganisms.
mycoplasma A pathogenic microorganism that passes through bacterial filters but has certain features in common with
myiasis A disease caused by the invasion of dipterous larvae.
myiasis Infestation with the maggots of flies.
myogenic flight muscles Flight muscles that contract repeatedly as a result of mechanical stretch and do not require
a nervous impulse for each contraction.
myogenic Produced by muscle; contraction of a muscle generated by that muscle itself, without neuronal stimulus.
myogenic rhythms Rhythms produced by spontaneously active muscles.
myrmecophile A symbiont found in the colonies of ants, usually living at the expense of the food in the nest.
myrmecophyte A plant that has special cavities in which ants live.
myriapod A many‑legged arthropod; a centipede, millipede, pauropod, or symphylan.
naiad An aquatic, gill‑breathing nymph.
nasute soldier (or nasutus) An individual of a termite caste in which the head narrows anteriorly into a snoutIike
natural control The maintenance of a population at nonoutbreak levels by natural environmental factors, biotic and
nebulous vein. A wing vein that is uniformly pigmented (not darker on its margins), without a tubular structure; it can
be seen with both reflected and transmitted light (cf. spectral, tubular veins).
necrophagous Feeding on dead animal matter.
nectar guide A streak on a flower that guides insects to nectar sources.
neopterous Possessing the ability to fold the wings backward over the abdomen.
neural lamella A fibrous, noncellular layer that surrounds and supports a ganglion.
neurogenic Produced by a neuron; contractions of muscle stimulated by a neuronal impulse. nidi In the midgut, clusters
of regenerative epithelial cells.
neurogenic flight muscles Flight muscles that contract each time a nerve impulse is received.
neurogenic rhythms Rhythms maintained by spontaneously active neurons.
neurohemal organ An organ associated with the nervous system that stores and releases hormones.
neuron Nerve cell.
neuropile The mass of closely packed nerve cell processes comprising the central part of a ganglion.
neurosecretory cell A cell of the nervous system that is specialized for the production and release of hormones.
niche The role that a species occupies in nature; that is, its precise habitat plus its behavior in that habitat.
nocturnal Active at night. node A knoblike or knotlike swelling.
nodilorm In the form of a knob or knot.
nodus A strong cross vein near the middle of the costal border of the wing (Odonata).
notal wing process Point at which the notum articulates with the wing (or axillary sclerites at the base of the wing).
notaulus (pl., notauli). The usually oblique, longitudinal groove on the mesoscutum, often dividing the mesoscutum
into medial and lateral parts. A longitudinal line on the mesoscutum of Hymen6ptera, marking the separation
of the dorsal longitudinal and dorsoventral flight muscles; also sometimes called notaulix notaulices),
parapsidal furrow, or parapsidal suture.
notopleural bristles Bristles on the notopleuron (Diptera).
notopleural suture. A groove separating the mesonotum from the mesopleuron. A suture between the notum and the
notopleuron (pl., notopleura) An area on the thoracic dorsum, at the lateral end of the transverse suture (Diptera).
notum (pl., nota; adj., notal). A thoracic tergum, usually subdivided into a scutum and a scutellum. A dorsal sclerite
of the insect thorax. The dorsal sclerite of a thoracic segment; the fused second gonapophyses of the
nuclear polyhedrosis virus (NPV) A vinus that multiplies in cell nuclei, chiefly in the epidermis, fat body, and blood
nurse cells Nutritive cells associated with the developing oocyte.
nymph An immature stage (following hatching) of an insect that does not have a pupal stage; the immature stage of
Acari that has eight legs.
oblique scutal carina. In Spheciformes, the ridge on the mesoscutum extending obliquely posteriorly and medially
from the lateral margin near the posterior of the tegula.
oblique vein A slanting cross vein; in Odonata, where Rs crosses M, 2.
obtect pupa A pupa in which the appendages are more or less glued to the body surface, as in the Lepid6ptera.
occipital carina. A ridge on the posterior surface of the head that separates the occiput from the vertex and gena; the
ventral part of the ridge is sometimes called the genal carina.
occipital foramen See foramen magnum.
occipital suture (or sulcus) A transverse suture in the posterior part of the head that separates the vertex from the
occiput dorsally and the genae from the postgenae laterally.
occiput (adj., occipital). The posterior part of the head behind the vertex dorsally and teh genae laterally. If an occipital
carina is present, the occiput is the area betwen it and the very narrow postocciput surrounding the foramen
magnum (also see postgena). The dorsal posterior part of the head, between the occipital and postoccipital
ocellar bristles Bristles arising close to the ocelli (Diptera).
ocellar triangle A slightly raised triangular area in which the ocelli are located (Diptera).
ocellus (pl., ocelli) A simple eye on the dorsal part of the head, containing a single facet. Hymenoptera usually have
3 ocelli: one median (anterior) and two lateral (posterior).
olfaction The sense of smell; the ability to detect chemicals in a gas.
oligolectic Utilizing a very limited number of plant species as sources of pollen (said chiefly of bees).
oligophagous Feeding on a somewhat restricted group of (often related) plant or animal species.
ocellus (pl., ocelli) A simple eye of an insect or other arthropod.
ocellus (pl., ocelli; adj., ocellar). A simple eye, consisting of a single, usually round or oval facet.
olistheter A tongue‑in‑groove mechanism connecting the first and second gonapophyses of the ovipositor.
ommatidium (pl., ommatidia) A functional unit of the compound eye, expressed extemally as a facet. A single unit
or visual section of a compound eye.
onisciform larva See platyform larva.
oogenesis The production of eggs.
oogonium ~pl., oogorlia~ The primary germ cells of the female.
ootheca A hardened protective structure surrounding the egg mass, composed of tanned protein and secreted by
accessory glands. The covering or case of an egg mass IMantodea, Blattaria.
open coxal cavity One bounded posteriorly by a sclerite of the next segment (front coxal cavities, Coleoptera), or one
touched by one or more pleural sclerites (middle coxal cavities, Coleoptera).
open cell A wing cell extending to the wing margin, not entirely surrounded by veins.
operculum (pl., opercula) A lid or cover.
opisthognathous With the mouthparts directed backward.
opisthorhynchous With the beak directed backward. oral Pertaining to the mouth.
oral cavity. The opening of the head from which the mouthparts are suspended.
oral vibrissae A pair of stout bristles, one on each side of the face near or just above the oral margin, and larger than
the other bristles on the vibrissal ridge (Diptera).
orbit. The narrow border around the eye. The inner and outer orbits are those parts of the face plus the frons and the
gena, respectively, immediately next to the eye.
orbital plate An area on the head above the antenna and next to the compound eye (Diptera); also called genovertical
order A subdivision of a class or subclass, containing a group of related superfamilies or families.
orthognathous. With mouth directed ventrad
osmeterium (pl., osmetena) A fleshy, tubular, eversible, usually Y‑shaped gland at the anterior end of certain
caterpillars (Papilionidae). An eversible gland on the thorax of the larvae of swallowtail butterflies that
ostia Segmentally arranged inlet pores in the walls of the heart.
ostiole A small opening.
ostium (pl., ostia) A slitlike opening in the insect heart.
outer vertical bristles The more laterally located of the large bristles on the vertex, between the ocelli and the
compound eyes (Diptera).
ovariole One of the tubules making up the ovary, in which the eggs are formed. A more or less tubular division of an
ovipositor The egg‑laying apparatus of insects, typically composed of two sets of valves or a tubular extension of the
ovisorption Resorption of eggs prior to the time of oviposition.
ovoviviporous Producing small larvae, the eggs having hatched inside the mother.
ovary The egg‑producing organ of the female.
oviduct The tube leading away from the ovary through which the eggs pass.
oviparous Laying eggs.
ovipore The external opening of the female reproductive system through which the eggs pass during oviposition.
oviposit To lay or deposit eggs.
ovipositor The egg‑laying apparatus; the external genitalia of the female.
ovipositor. In females, a slender, paired and interlocking, saw-like or tubular structure used for laying the eggs or, in
Aculeata, for stinging or, in some Ichneumonoidea, for both; it may be concealed or may extend beyond the
apex of the body and is protected by a pair of ovipositor sheaths.
ovipositor sheath. A paired, slcerotized structure enclosing the external part of the ovipositor.
oviscapt Modification of the terminal abdominal segments of a female to serve as an egg‑laying organ.
paedogenesis Reproduction by larviform individuals.
paleopterous Lacking the ability to position the wings backward over the abdomen.
palpus (pl., palpi) A paired, segmented appendage arising on the maxilla or labium and serving sensory functions associated with food ingestion.
panoistic ovary An ovary in which the ovarioles lack nurse cells.
parasite An animal that completes its development on or in another animal but does not normally kill it.
parasitoid An insect that lives in its immature stages in or on another insect, which it kills after completing its own
parental investment Behavior of a parent that increases the probability of offspring survival at the cost of the parent's
ability to produce more offspring.
parthenogenesis Production of young from unfertilized eggs.
paedogenesis The production of eggs or young by an immature or larval stage of an animal.
palp A segmented process born by the maxillae or labium.
palpifer The lobe of the maxillary stipes that bears the palp.
palpiform. Segmented process
palpiger The lobe of the mentum of the labium that bears the palp.
palpus (pl., palpi; adj., palpal). Paired sensory appendages of the maxilla and labium, consisting of 1-6 segments and
1-4 segments, respectively.
panoistic ovariole Ovariole without nurse cells.
papilla A small nipplelike elevation.
paraglossa (pl., paraglossae). A paired, lateral lobe of the labium articulated basally with the prementum lateral to the
base of the glossa. One of a pair of lobes at the apex of the labium, laterad of the glossae.
paramere A structure in the male genitalia of insects, usually a lobe or process at the base of the aedeagus.
paranotum Lateral expansion of the notum.
paraproct One of a pair of lobes bordering the anus lateroventrally.
parasite An animal that lives in or on the body of another living animal (its hostl, at least during a part of its life cycle,
feeding on the tissues of its host; most entomophagous insect parasites kill their host (see parasitoid I
parasitic Living as a parasite.
parasitoid An animal that feeds in or on another living animal for a relatively long time, consuming all or most of its
tissues and eventually killing it (also used as an adjective, describing this mode of life~. Parasitoid insects in
this book are referred to as parasites.
parthenogenesis Development of the egg without fertilization .
patella A leg segment between the femur and tibia (arachnids).
paurometabolous With simple metamorphosis, the young and adults living in the same habitat, and the adults winged.
pecten A comblike or rakelike structure.
pectinate Comblike; that is, having a series of slender projections from an elongate shaft. With branches or processes
like the teeth of a comb; pectinate antenna; pectinate tarsal claw.
pedicel The second, usually small, segment of the antenna; the stem of the abdomen, between the thorax and the gaster
pericardial sinus A space around the heatt, limited below by the dorsal diaphragm.
perineurium The layer of cells surrounding a ganglion, which secretes the neural lamella.
peripneustic. Lateral spiracles on the abdomen.
peritrophic membrane The delicate, tubular sheath that surrounds the food within the midgut .
petiole. narrow stem attaching abdomen to thorax
phagostimulant A natural plant substance that induces feeding by an insect.
pharate stage A stage in which molting has occurred but the insect has not cast off the old cuticle.
pharynx A muscular portion of the foregut, just behind the mouth.
phenological asynchrony Lack of synchrony between the life cycle of a pest and the appropriate stage of its host plant.
pheromone An extemal chemical messenger that passes between individuals of the same species and controls
phoresy A condition in which an individual is carried about by another individual without harming that individual.
phylogeny The study of the history of lines of evolution .
physical gill A bubble or packet of air that adheres to the body of an aquatic insect and is continuous with the tracheal
phytoecdysone A plant product that mimics ecdysone.
phytotoxemia A diseaselike plant condition produced by the injection of toxic substances by insects.
plastron A framework of stiff, water‑repellent hairs or cuticular structures on the bodies of aquatic insects, containing
a film of air into which oxygen diffuses from the water.
pleural suture A vertical or oblique suture marking an intemal ridge of the thoracic pleuron, running from the dorsal
coxal articulation to the pleural wing process.
pleural wing process A fulcrum for the wing base, formed at the top of the intemal ridge fommed by the pleural suture.
pleuron (pl., pleura) A lateral sclerite of the thorax.
pedicel. The 2nd primary division or segment of the antenna; it articulates apically with the flagellum and basally with
pedipalps The second pair of appendages of an arachnid.
pedunculate. An intermediate, club-like condition between sessile and petiolate (also see petiolate).
pelagic Inhabiting the open sea; ocean‑dwelling.
penultimate Next to the last.
pericardial sinus The body cavity surrounding the dorsal blood vessel, limited ventrally by the dorsal diaphragm.
perineural sinus The body cavity surrounding the ventral nerve cord, limited dorsally by the ventral diaphragm.
peristalsis Waves of contraction.
peristome The ventral margin of the head, bordering the mouth.
peritrophic membrane A membrane in insects secreted by the cells lining the midgut; this membrane is secreted when
food is present and forms an envelope around the food; it usually pulls loose from the midgut, remains around
the food, and passes out with the feces.
perivisceral sinus The body cavity surrounding the digestive system, reproductive system, etc., between the dorsal and
petiolate Attached by a narrow stalk or stem.
petiolate. Stalked, drawn out into an extended process.
petiole A stalk or stem; the narrow stalk or stem by which the abdomen is attached to the thorax (Hymenoptera~; in
ants, the nodelike first segment of the abdomen.
petiole. Part of the metasoma, usually metasomal segment 1; the usually narrow, parallel-sided stalk joining the rest
of the metasoma to the propodeum.
pH A measure of the acidity or alkalinity of a medium A pH value of 7.0 indicates neutral; lower values indicate acid,
and higher values alkaline. Defined as ‑log IH~I.
phallotreme External opening of the male reproductive system on the aedeagus.
phallus The male copulatory organ, including any processes that may be present at its base.
pharynx The anterior part of the foregut, between the mouth and the esophagus.
pheromone A substance given off by one individual that causes a specific reaction by other individuals of the same
species, such as sex attractants, alarm substances, etc.
photoperiod The relative amount of time during
phragma (pl., phragmata) A platelike apodeme or invagination of the dorsal wall of the thorax.
phylum (pl., phylal) One of the dozen or so major divisions of the animal kingdom.
phytophagous Feeding on plants.
pictured With spots or bands (pictured wings.
pilifer One of a pair of lateral projections on the labrum (Lepidoptera).
pilose Covered with hair.
placoid sensillum (pl., placoid sensilla). An elongated, appressed, plate-like or rounded roof-like or groove-like sensory structure; it is usually used when referring to the flagellar segments.
planidium larva A type of first‑instar larva in certain Diptera and Hymenoptera that undergoes hypermetamorphosis;
a larva that is legless and somewhat flattened.
plantar lobe. A small membranous pad projecting from the ventral apex of tarsomeres 1-4.
plastron A bed of very dense and very fine hairs used to hold an air bubble close to the body and across which gas
exchange takes place.
platyform larva A larva that is extremely flattened, as the larva of Psephenidae; also called onisciform larva.
pleural wing process The structure articulating with the wing (specifically with the second axillary scleritej.
pleural apophysis (or arm j Internal process extending from the pleural suture to the sternal apophyses. pleural suture
(or sulcusl A suture of a thoracic pleuron extending from the base of the wing to the base of the coxa, which
separates the episternum and epimeron.
pleural Pertaining to the pleura, or lateral sclerites of the body; lateral.
pleural groove. A groove on the mesopleuron and metapleuron extending between the wing base and the coxal
articulation; it separates the episternum from the epimeron.
pleurite A lateral or pleural sclerite.
pleuron (pl., pleura) The lateral area of a segment.
pleuron (pl., pleura; adj., pleural). The lateral part of a body segment, usually of a thoracic segment where the pleuron
occupies the lateral as well as the ventral areas of the mesothorax and metathorax.
pleuropodium Embryonic appendages of the first abdommal segment.
pleurotergite A sclerite containing both pleural and tergal elements.
plumose Featherlike; plumose antenna.
podite A segment of an arthropod leg, moved by muscles inserted in its base.
polyculture A mixed stand of crop plants.
polyembryony Division of a single egg to form several identical embryos.
polyethism The presence of several discrete types of behavior by different groups of individuals in colonies of social
polylectic Utilizing a variety of plant species as sources of pollen.
polymorphism The presence of two or more distinct, structurally different types of individuals within the same stage
of one species.
polyphagous Feeding on a broad array of plant or animal species.
population dynamics The forces that control population size, and their effects.
population regulation The maintenance of an approximately constant population size and density, and the forces that
population resilience The capacity of a population to adapt to change or to persist in a changing environment.
population stability The ability of a population to absorb disturbance and to return to an equilibrium state.
precoccinelline A defensive allomone produced by lady beetles during autohemorrhage.
precocene An insect growth regulator produced by certain plants that depresses the source of juvenile hormone.
preimaginal conditioning Conditioning of an immature insect that persists into the adult stage.
prepupa A resting stage of the last larval instar, prior to the molt to the pupal stage.
pretarsus The most distal segment of the insect leg, bearing the claws and arolium.
primary defense A defense mechanism that is continuously present, such as crypsis.
primer pheromone A pheromone that acts to modify the phvsiological state of an animal.
proctodeum The hindgut of insects.
procuticle The inner zone of the insect cuticle, containing chitin and protein, divisible into exocuticle and endocuticle.
progressive provisioning The supplying of food to the offspring over time, as the offspring grow.
proleg A fleshy, unjointed "false leg," occurring ventrally on the abdomen of caterpillars and other larval insects.
poikilothermous Cold‑blooded, the body temperature rising or falling with the environmental temperature.
point A small triangle of stiff paper, using in mounting small insects.
pollen basket See corbicula.
pollen rake A comblike row of bristles at
polyembryony An egg developing into two or more embryos.
polytrophic ovariole Meroistic ovariole in which trophocytes pass into the vitellarium with the oocyte.
porrect Extending forward horizontally; porrect antennae.
postabdomen The modified posterior segments of the abdomen, which are usually more slender than the anterior
segments (Crustacea); see also the postabdomen in a scorpion.
postalar callus A rounded swelling on each side of the mesonotum, between the base of the wing and the scutellum
posterior Hind or rear.
posterior cross vein A cross vein at the apex of the discal cell (Diptera)
posterior lingual plate. A sclerite on the posterior (ventral) surface of the glossa.
posterior cell One of the cells extending to the hind margin of the wing, between the third and sixth longitudinal veins
postgena (adj., postgenal). The lower part of the occiput; when the occipital carina is absent, the gena and postgena
are continuous, and the entire lower area constitutes the gena (also see occiput).
postgena (pl., postgenae) A sclerite on the posterior lateral surface of the head, posterior to the gena.
postgenal bridge Mesal extension of the postgenae on each side to meet below the foramen magnum.
posthumeral bristles Bristles on the anterolateral surface of the mesonotum, just posterior to the humeral callus
postmarginal vein The vein along the anterior margin of the front wing, beyond the point where the stigmal vein arises
postmentum The basal portion of the labium, proximad of the labial suture.
postnodal cross veins A series of cross veins just behind the costal margin of the wing, between the nodus and stigma,
and extending from the costal margin of the wing to Rl (Odonata).
postnotum (pl., postnota) A notal plate behind the scutellum bearing a phragma, often present in wing‑bearing
segments. A posterior sclerite of the mesonotum and metanotum behind the scutellum. The postnotum of the
metathorax is fused dorsally with abdominal tergum 1 and laterally with the metepimeron; in Apocrita the
postnotum is seldom visible, and then only as an impressed line in front of the propodeum.
postoccipital suture The transverse suture on the head immediately posterior to the occipital suture.
postocciput (adj., postoccipital). A narrow area surrounding the foramen magnum; it is separated from the occiput by
the postoccipital groove. The extreme posterior rim of the head, between the postoccipital suture and the
postpectal carina. In Ichneumonoidea, the posterior transverse carina ventrally on the mesopleuron, just in front of
postpetiole The second segment of a two‑segmented pedicel jantsl.
postscutellum A small transverse piece of a thoracic notum immediately behind the scutellum, in Diptera, an area
immediately behind or below the mesoscutellum.
postvertical bristles A pair of bristles behind the ocelli, usually situated on the posterior surface of the head (Diptera).
preapical Situated just before the apex; preapical tibial bristles of Diptera.
prebasilare A narrow transverse sclerite, just basal to the mentum in the gnathochilarium of some millipedes.
precosta The most anterior of the major longitudinal wing veins laccording to Kukalova‑Peckl.
predaceous Feeding as a predator.
predator An animal that attacks and feeds on other animals (its prey), usually animals smaller or less powerful than
itself. The prey is usually killed and mostly or entirely eaten; many prey individuals are eaten by each predator.
prefemur The second trochanter segment of the leg.
pregenital Anterior to the genital segments of the abdomen.
prementum The distal part of the labium, distad of the labial suture, on which all the labial muscles have their
prementum. A labial sclerite that articulates basally with the mentum and bearing the glossae, paraglossae, and palpi
preoral Anterior to or in front of the mouth.
prepectus An area along the anteroventral margin of the mesepisternum, set off by a suture (Hymenoptera)
prepectus. A sclerite of the thorax between the pronotum and the mesepisternum (also see epicnemium).
prepupa A quiescent stage between the larval period and the pupal period; the third instar of a thrips.
prestigma. The enlarged and sclerotized apex of one or more veins on the anterior margin of the wing basal to the
costal notch and almost continuous with the stigma.
presutural bristles Bristles on the mesonotum immediately anterior to the transverse suture and adjacent to the
pretarsus (pl, pretarsi) The terminal segment of the leg, typically consisting of a pair of claws and one or more padlike
pretarsus. The apical segment of a leg, bearing teh claws and associated structures (also see arolium).
pro-. A Latin prefix meaning "before" or "anterior"; used with Latin, latinized, or Greek words to indicate the anterior
(usually 1st) part of a structure.
proboscis The extended beaklike mouthparts.
proclinate Inclined forward or downward.
proctodaeum The hindgut, or the hindmost of the three major divisions of the alimentary tract, from the Malpighian
tubules to the anus.
procuticle The form in which the cuticle is initially secreted by the epidermis, before sclerotization takes place.
produced Extended, prolonged, or projecting.
proepimeron (pl., proepimeral) The epimeron of the prothorax.
proepisternum (pl., proepisterna) The episternum of the prothorax.
profile The outline as seen from the side or in lateral view.
prognathous Having the head horizontal and the mouthparts projecting forward.
prognathous. With the head somewhat in the same plane as the body (horizontal) so the mouthparts are directed
anteriorly (cf. hypognathous).
proleg One of the fleshy abdominal legs of certain insect larvae.
prominence A raised, produced, or projecting portion.
prominent Raised, produced, or projecting.
promote To move anteriorly.
pronate To turn the leading edge of the wing downward.
pronotal collar The horizontal surface of the posterior to the sloping, and often narrowing, region
immediately behind the head.
pronotal comb A row of strong spines borne on the posterior margin of the pronotum (Siphonaptera).
pronotal flange The anterior projected rim of the pronotum; it is often hidden by the head.
pronotal lobe. The rounded posterolateral extension of the pronotum that covers the mesothoracic spiracle.
pronotal plate. In Cynipoidea, the dorsal disc of the pronotum.
pronotum (adj., pronotal). The dorsal sclerite of the prothorax; in most Hymenoptera, occupying also the dorsolateral
or lateral part of the prothorax. The dorsal, often shieldlike sclerite of the prothorax.
propleural bristles Bristles located on the propleuron (Diptera).
propleuron (pl., propleural) The lateral portion, or pleuron, of the prothorax.
propleuron (pl., propleura). The lateral part of the prothorax. In Hymenoptera, it is displaced a bit by the pronotum
so as to occupy an oblique position ventrolateral and anterior to the pronotum.
propneustic. Lateral spiracles on the thorax.
propodeal carina. In Ichneumonoidea, one or more named, usually distinct, transverse or longitudinal ridges on the
propodeum (adj., propodeal). In Apocrita, the first tergum of the abdomen, widely and immovably fused with the
metanotum and with each metapleuron of the thorax, and usually narrowly and flexibly joined to the rest of
the abdomen (also see abdomen, metasoma, thorax). The posterior portion of the thorax, which is actually the
first abdominal segment united with the thorax (Hymenoptera, suborder Apocrita).
proprioception Detection by an animal of
proprioreceptor A sense organ that detects the relative position of parts of an animal's own body.
prosoma A term referring to the anterior part of the body, usually applied to the cephalothorax; the anterior part of the
head or cephalothorax.
prosternum. A ventral sclerite of the prothorax, between the propleura. The sternum, or ventral sclerite, of the
protelean parasite An entomophagous insect that attacks its prey only when the attacking insect is immature, the adult
being free living.
prothoracic glands Endocrine organs located in the prothorax of immature insects, secreting molting hormone.
Endocrine glands located in the prothorax generally that secrete ecdysone.
prothoracicotropic hormone (PTTH) A hormone secreted by neurosecretory cells of the brain and serving to activate
the prothoracic glands.
prothorax. The first of the 3 primary subdivisions of the thorax, composed of the pronotum, the propleuron, and the
prosternum. The anterior of the three thoracic segments.
protocerebrum The largest and most anterior part of the brain, which includes the optic lobes. The dorsal lobes of the
brain, innervating linter alial the compound eyes and ocelli.
protonymph The second instar of a mite.
proventriculus The portion of the foregut, just before the midgut, that controls entry of food into the midgut; often
lined with sclerotized teeth that grind the food. The valve between the foregut and midgut.
proximad Toward the end or portion nearest the body.
proximal Nearer to the body or to the base of an appendage. Referring to the part of an appendage that is closest to
prozonite The anterior portion of a millipede tergum when the tergum is divided by a transverse groove.
pruinose Covered with a whitish waxy powder.
pseudarolium jpl., pseudarolial A pad at the apex of the tarsus resembling an arolium.
pseudocercus ipl., pseudocerci~ See urogomphi.
pseudocubitus A vein appearing as the cubitus, but actually formed by the fusion of the branches of M and Cu,
pseudomedia A vein appearing as the media, but actually formed by the fusion of branches of Rs (Neuroptera).
pseudopupa A coarctate larva; a larva in a quiescent pupalike condition, one or two instars before the true pupal stage
pseudovipositor See oviscapt.
pteralia See axillary sclentes.
pterygote A winged insect, or a wingless insect believed to have been derived from winged ancestors.
pteropleural bristles Bristles on the pteropleuron (Diptera).
pteropleuron jpl., pteropleura1 A sclerite on the side of the thorax just below the base of the wing, and consisting of
the upper part of the mesepimeron (Diptera).
pterostigma A thickened opaque spot along the costal margin of the wing, near the wing tip lalso called the stigmal
pterothorax The wing‑bearing segments of the thorax (mesothorax and metathoraxl.
pterygote Winged; a member of the subclass Pterygota.
ptilinum A temporary bladderlike structure that can be inflated and thrust out through the frontal lor ptilinal~ suture,
just above the bases of the antennae, at the time of emergence from the puparium (Diptera) See brain hormone.
pubescence. The short, fine, often closely set setae on the body.
pubescent Downy, covered with short fine hairs.
pulvilliform Lobelike or padlike; shaped like a pulvillus; pulvilliform empodium.
pulvillus (pl., pulvilli) A pad or lobe beneath each tarsal claw (Diptera).
punctate Pitted or beset with punctures.
punctate. Having fine, impressed points or pits.
punctiform. With impressed pits or depressions)
puncture A tiny pit or depression.
pupa (pl., pupae) The stage between the larva and the adult in insects with complete metamorphosis, a nonfeeding and
usually an inactive stage.
pupariation Formation of the puparium by larvae of Diptera.
puparium (pl., puparia) A case formed by the hardening of the last larval skin, in which the pupa is formed.
pupate To transform to a pupa.
pupiparous Giving birth to larvae that are full grown and ready to pupate.
pygidial plate. A specialized area of the tergum of the last externally visible segment of the metasoma; it is usually
flattened and defined laterally by ridges or grooves.
pygidium The last dorsal segment of the abdomen.
pyloric valve The valve between the midgut and hindgut.
quadrangle A cell immediately beyond the arculus (Odonata, Zygoptera)
qualitative defenses of plants Toxins and small‑molecular‑weight compounds (such as alkaloids) that are active
against the physiological systems of phytophagous insects.
quantitative defenses of plants Complex, digestibility‑reducing substances (such as tannins) that reduce the ability
of insects to feed on plants.
queen substance A pheromone produced by the queen honey bee and serving various functions in the hive as well as
during mating and swarming flights.
radial cell A cell bordered anteriorly by a branch of the radius; the marginal cell (Hymen6ptera)
radial cross vein A cross vein connecting Rl and the branch of the radius immediately behind it.
radial sector The posterior of the two main branches of the radius.
radicle. The basal part of the scape often strongly defined by a constriction; it articulates with the torulus.
radius The longitudinal vein between the subcosta and the media.
raptorial Fitted for grasping prey; raptoriai front legs.
reaction chain A continuous series of behavioral acts, each of which is dependent on completion of the preceding act.
reclinate Inclined backward or upward.
rectal pad A portion of the rectum containing enlarged cells, responsible for active water and ion uptake from the
contents of the rectum.
rectum The posterior region of the hindgut.
recumbent. Referring to a seta lying parallel to the body surface.regulatory control The use of enforceable regulations
to prevent the spread of a pest or to suppress or eradicate it.
recurrent vein One of two transverse veins immediately posterior to the cubital vein (Hymenoptera); a vein at the base
of the wing between the costa and the subcosta, extending obliquely from the subcosta to the costa
recurved Curved upward or backward.
releaser An environmental or communicative stimulus that triggers a fixed action pattern.
releaser pheromone A pheromone that acts via the central nervous system to produce a quick behavioral response.
releasing mechanism An innate capacity to respond in a particular way to a specific stimulus .
remote To move posteriorly.
resilin A rubberlike, proteinaceous constituent of the insect procuticle.
resting potential The slight charge that can be measured in an unstimulated nerve cell.
reticulate. Covered with a network of lines; meshed or webbed. Like a network.
retina The receptive apparatus of an eye.
retinula cell A monopolar sensory neuron within an ommatidium of the compoun‑l eye.
retractile Capable of being pushed out and drawn back in.
rhabdom The central, rodlike element in an ommatidium, consisting of several rhabdomeres, one from each retinula
cell. A rodlike light‑sensitive structure formed of the inner surfaces of adiacent sensory cells in the omma
tidium of a compound eye.
Riker mount A thin glass‑topped exhibition case filled with cotton.
rostrum Beak or snout.
round dance A torm of recruitment in the honey bee, used when a food source close to the hive is communicated to
royal jelly A nutritive substance produced by glands in the heads of worker honey bees and fed to the larvae. Larvae
fed this diet throughout development produce queens.
r‑strategist A species characterized by having rapid development, high motility, and a high reproductive rate relative
to a K‑strategist .
rudimentary Reduced in size, poorly developed, embryonic.
saprophagous feeding on dead or decaying plant or animal materials, such as carrion, dung, dead logs, etc.
saprophagous Feeding on dead organic matter.
scape The most basal segment of the antenna. The first primary division or segment of the antenna; it articulates
apically with the pedicel and basally with the torulus.
scapula (pl., scapulae) One of two sclerites on the mesonotum immediately lateral of the notauli (Hymenoptera); also
scarabaeiform larva A grublike larva, that is, one with the body thickened and cylindrical, with a well‑developed head
and thoracic legs, without prolegs, and usually sluggish.
scavenger An animal that feeds on dead plants or animals, or decaying materials, or on animal wastes.
scent gland A gland producing an odorous substance.
scientific name A latinized name, internationally recognized, of a species or subspecies. The scientific name of a
species consists of the generic and specific names, and that of a subspecies consists of the generic, specific,
and subspecific names. Scientific names are always printed in italics.
sclerite A more or less rigid cuticular plate. A hardened body‑wall plate bounded by sutures or membranous areas.
A hardened plate of the integument; it is separated from other such plates by sutures or membrane.
sclerotin Cuticular protein that has been hardened and darkened through cross‑linkage of the molecules.
sclerotization The process of becoming hardened.
sclerotized Hardened. Referring to the body integument; relatively stiff and usually darkly pigmented areas compared
with usually colorless and flexible membranous areas.
scolopidium A sensillum located beneath the cuticle and modified for the reception of vibrations .
scolopophorous organ See campaniform sensillum.
scolytoid larva A fleshy larva resembling the larva of a scolytid beetle.
scopa (pl., scopae). In Apiformes, a brush-like structure of short stiff hairs of equal length used for collecting pollen.
A small, dense tuft of hair.
scramble competition Competition in which many individuals "scramble" for a limited resource, such as food.
scraper The sharpened anal angle of the front wing jtegmenl of a cricket or long‑horned grasshopper, a part of the
scrobal groove. A horizontal groove on the mesopleuron that may be continuous with the episternal groove anteriorly
and ends at the pleural groove posteriorly.
scrobe (adj., scrobal). A groove or furrow; antennal scrobe. A groove in the body integument for the reception or
concealment of an appendage, e.g., a longitudinal depression of the head above each torulus for reception of
the scape or a groove on the mesopleuron for reception of the mesofemur; the scrobe of the mesepisternum is
a small pit.
sculpture. Markings or a pattern of impressions or elevations on the surface of a structure.
scutellum (pl., scutella; adj., scutellar). The middle region of the mesonotum or metanotum, behind the scutum. In
Apocrita, only the mesoscutellum is evident and is simply named the scutellum, whereas in Symphyta both the
mesoscutellum and metascutellum are present. A sclerite of the thoracic notum; the mesoscutellum, appearing
as a more or less triangular sclerite behind the pronotum (Hemiptera, Homoptera, Coleoptera).
scutum (pl., scuta; adj., scutal). The anterior sclerite of a notum, in front of the scutellum. In Apocrita, the
mesoscutum is functionally only the area in front of the transscutal articulation; the axilla, although
morphologically part of the mesoscutum, is treated separately (also see axilla). The middle division of a
thoracic notum, just anterior to the scutellum.
sebaceous glands Glands secreting fatty or oily material.
secondary defense A defensive mechanism that is brought into play only in the presence of a threat--for example, an
secondary pest An insect that does not normally attain pest status except when insecticides destroy its natural enemies.
secondary plant substance A substance produced by a plant that plays no role in the basic metabolism of the plant.
sectorial cross vein A cross vein connecting two branches of the radial sector.
segment. A ring or subdivision of the body or of an appendage between areas of flexibility, and bearing intrinsic
muscles. A subdivision of the body or of an appendage, between joints or articulations.
seminal vesicle An expansion of the vas deferens of the male in which sperm are stored. A structure, usually saclike,
in which the seminal fluid of the male is stored before being discharged; usually an enlargement of the vas
semiaquatic Living in wet places or partially in water.
sense cone or sense peg A minute cone or peg, sensory in function.
sensillum (pl., sensilla) An integumental sense organ, consisting of sensory neurons and associated cuticular structures.
A simple sense organ, such as a seta, or one of the structural units of a compound sense organ. An organ
capable of detecting external stimuli.
sensory filtering The process of receiving only certain specific stimuli among the many potential stimuli impinging
on the body.
sensory neuron A neuron capable of generating an action potential in response to an external stimulus lsuch as physical
displacement, temperature, humidity, chemicals, etc.l.
serial homology Homology within an insect due to the repetition of components of an organ system in each body
serrate Toothed along the edge like a saw; serrate antenna.
sessile Attached or fastened, incapable of moving from place to place; attached directly, without a stem or petiole. One
structure attached to another, without a distinct constriction (cf. pedunculate, petiolate).
seta (pl., setae; adj., setal). A slender, hair-like, usually sensory extension of the cuticle, connected to the body wall
by a socket. A bristle. A movable hair of the integument, typically forming a sensillum.
setaceous Bristlelike; setaceous antenna.
setate Provided with bristles.
setulose Bearing short, blunt bristles. sigmoid Shaped like the letter S.
sibling species Closely related species that are difficult to distinguish by ordinary means.
sign stimulus A stimulus for which an animal has evolved a specific response pattem.
simple Unmodified, not complicated; not forked, toothed, branched, or divided.
social parasite An insect that invades or lays its eggs in the nest of another insect and develops on food in the nest.
spatulate Spoon‑shaped; broad apically and narrowed basally, and flattened.
species A group of individuals or populations that are similar in structure and physiology and are capable of
interbreeding and producing fertile offspring, and that are different in structure and/or physiology from other
such groups and normally do not interbreed with them.
spectral vein. A wing vein that is indicated only by a ridge or furrow on the wing surface; it has no trace of pigment
and cn only be seen with reflected light (cf. tubular, nebulous veins).
sperm duct A tube connecting the bursa copulatrix of ditrysian Lepid6ptera to the vagina.
sperm follicle A tubelike subdivision of the testis in which spermatogenesis occurs.
sperm precedence In multiple matings, the tendency for sperm from the most recent mating to fertilize the eggs.
spermatheca (pl., spermathecae) A saclike structure in the female in which sperm from the male are received and
often stored. A small sac associated with the median oviduct of the female, in which sperm are stored