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1 Ululodes hyalina Latr. of the southern United States
and Central America was studied by McClendon (1902). Eggs are laid in groups of 57-75 in a
double row at the end of a twig, and the mass is fenced off slightly below
the base by several circles of "repagula" placed on end. These repagula are thought to be aborted
eggs, produced by certain ovarian tubules at the same time that others form
normal eggs. This formation is
thought to protect the egg mass from natural enemies. The incubation period is 9-10 days. Larvae hide
in depression in soil or under the edges of stones and cover their bodies
with sand or dust. While awaiting
prey, the huge mandibles are held widely separated. The closing of the jaws is seemingly triggered by contact, and
the prey is usually paralyzed within seconds by the bite. The body fluids of the prey are absorbed
through a duct formed by the fitting together of curved mandible and
maxilla. There are 3 larval instars,
and development takes ca. 62 days. Helicomitus dicax Wlk. lays dark brown eggs in
single rows, each of which contains as many as 40 (Ghosh 1913). There are 3 larval instars, the larvae
living on the ground surface, beneath a dust covering which conceals all but
the mandibles. These are used in
placing the particles of dust or sand on the back, and each mandible can be
moved independently of the other (Clausen 1940/62). The pupa emerges from the cocoon by bursting it rather than by
dissolving or cutting an opening.
There is one generation annually, and overwintering is as active
larvae. Pseudoptynx sp. larvae
do not have a covering of sand or debris, but rather conceal themselves in
tree bark depressions (Gravely & Maulik 1911). Here they are inconspicuous, their legs being hidden and their
mandibles so widely separated that they lie along the sides of the head and
thorax. Larvae of Ascalaphus insimulans Wlk. assemble in linear groups on plant stems, with
their bodies overlapping, so that only the heads and widespread mandibles are
visible (Clausen 1940/62). Wheeler
(1930) noted several species that rely on protective coloration rather than a
soil covering. One undermined species
from Panama had a greenish-colored larva that inhabited the leaves of trees
and lay with its body flattened along the mid-rib on the upper surface. When awaiting prey, the mandibles were
opened so widely that they were completely hidden beneath the lateral margins
of the thorax. These "owlflies" has habits that are
similar to the Myrmeleontidae. The
larvae wait for their prey, which includes a variety of soft-bodied
insects. However, they do not
construct pits., but rather utilize natural depressions to hide and often
cover their bodies with dust. The
larvae are different from the true ant lions because they walk forward rather
than backward. The adults look a lot
like dragonflies but may be distinguished by a long, clubbed antenna. They are crepuscular or nocturnal in
behavior. Adults are strong fliers
just like dragonflies. There are
periods of hovering and rapid flight, when the adults feed on small
insects. It has been noted that
adults rest a lot, and usually with their head held down on a vertical twig,
from which the body projects a right angle thus appearing as a small twig
(Borror et al. 1989). They do not fly
off directly from a resting position, but must go through a preparation
period of several minutes while they vibrate their wings. The wings in some adults are colored. References: Please refer to <biology.ref.htm>, [Additional references
may be found at: MELVYL
Library] Borror, D. J., C. A. Triplehorn & N. F.
Johnson. 1989. An Introduction to the Study of Insects,
6th Ed. Saunders Coll. Publ., Philadelphia. 875 p. |