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<phycitid.htm> [For
educational purposes only] Glossary <Principal Natural Enemy Groups > <Citations> <Home> |
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LEPIDOPTERA, Phycitidae -- <Images>
& <Juveniles> Please refer also to the following links for details on this
group: This largely phytophagous of scavenger family
contains several species which feed entirely on other insects, especially in
the orders Lepidoptera and Homoptera.
Phytica dentilinella Hamp. is a predator of pupae of several Lepidoptera
in India. During some seasons it is
found abundantly in cocoons of the nettle grub, Parasa lepida Cram.
(Ayyar 1929). It is thought that the
young Phycita larva reaches the
host prior to cocoon formation.
Infested cocoons have thinner walls than those of healthy hosts, and
this indicates a certain amount of feeding by the predator larva while the
host was still active (Clausen 1940/1962). An undescribed species from southern Africa was
studied by van der Merwe (1921). One
to 6 1st instar larvae were found on almost mature larvae of Dasychira extorta on the foliage of fig trees. Feeding was very extensive on the body fluids of the Dasychira larva, and after its death
the predator may move to another host.
Oviposition was not observed, but eggs were found on cast skins. The young larvae apparently do not feed
extensively until the host spins its cocoon.
Thereafter occurs a rather long resting period, after which either the
host larva or the pupa is quickly consumed.
Mature larvae measure 25 mm. long, and the larval period ranges from
6-12 months, and the pupal period from 18-30 days. Adults show mostly during late summer. Clausen (1940) believed that this species
was far advanced toward obligate parasitism, because of the ability of some
individuals to attain maturity on a single host. Ayyar (1929) recorded Euzophera cocciphaga
Hamp. as a predator on the eggs and young larvae of the giant monophlebine
coccid, Aspidoproctus xyliae Gr., infesting rain trees in
India. The greenish-yellow eggs are
laid singly on the host's dorsum, most often in the posterior region. Newly hatched caterpillars crawl about
over the scale for a while but eventually find their way beneath the
body. One to 3 larvae may be found
beneath each scale. Shortly after
feeding begins, they securely fasten the margins of the scale insect to the
substratum with silken strands. This
is thought to serve the purpose of preventing emergence of the host larvae
after hatching. It was observed that
no larvae ever emerged from parent scales known to be infested, and yet when
a passageway was made through the silken barrier they emerged in
numbers. Mature parasitoid larvae are
grayish-green and ca. 6.5 mm. long.
Pupation occurs within a tubular cocoon beneath the host remains. Other Indian species of this genus are
known as stem borers or fruit feeders. Laetilia coccidivora Comst. is
a predator on the terrapin scale, Lecanium
nigrofasciatum Perg., and attacks
others also, particularly Ceroplastes,
Icerya and Pulvinaria (Simanton 1916a).
First brood eggs are laid singly among the mature scales during early
June, and feeding is mainly on gravid females. A delicate silken tube is constructed from scale to scale,
within which pupation occurs. Larvae
of the second brood feed on the young scales during late summer. Vitula
saissetiae Dyar is predaceous on Saissetia sp. in Panama, and the
larvae of V. edmandii Comst. has been collected in bumblebee nests in North
America (Clausen 1940/1962). Cereobata coccophthora Turn. is
predaceous on Eriococcus, and its
behavior, including the provision of a dorsal shield, is quite similar to
that of the noctuid Eublemma. Cryptoblabes
gnidiella Mill., normally feeds on
plant foliage, but it also has been observed to feed extensively on the
various stages of Aleurocanthus
spp. in Malaya (Clausen 1940/1962). References: Please refer
to <biology.ref.htm>, [Additional
references may be found at: MELVYL Library] |