Page 318 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Zygaenidae
DISTRIBUTION Northeast India, Indochina, southern China,
Chinese Taipei, and Japan
HABITAT Forested mountain slopes and valleys
HOST PLANTS Helicia spp., Buddleja spp., Co ea spp., Hibiscus spp.,
and tallow (Triadica spp.)
NOTE Caterpillar that advertises its noxiousness with classic
aposematic colors
CONSERVATION STATUS Not evaluated, but not uncommon

ADULT WINGSPAN
2¾–3⅛ in (70–80 mm)
CATERPILLAR LENGTH
1 ⁄ –1⅜ in (30–35 mm)

ERASMIA PULCHELLA
ERASMIA PULCHELLA
316
HOPE, 1841

Erasmia pulchella caterpillars are not cryptic and make no e ort
to conceal themselves from potential threats while feeding on the
topsides of leaves. Their defensive strategy is one of aposematic
red and yellow warning coloration, distasteful cyanogenic body
secretions, urticating hairs and spines, and ambiguous head
and tail anatomy. The main natural threat they face is from
parasitoids, particularly braconid wasps, against which they
have no defenses. The speci c parasitoids of the Chalcosiine

subfamily to which E. pulchella belongs have been able to adapt
to detoxify hydrocyanic acids, thus bypassing the group’s main
defensive mechanism.

Pupation occurs beneath a parchment-like silken sheet formed
over a concavity on the host plant leaf or adjoining vegetation or
in leaf litter. Adult moths are stunningly colored and iridescent
and highly prized in collections. They fly over the summer
months and inherit their distastefulness from the larval stage.
In the adult, this is expressed as a toxic froth, which bubbles from
thoracic glands when the moths are threatened.
Actual size

The Erasmia pulchella caterpillar is black,
with each segment ringed by six protuberances
topped with setae. The lateral, cranial, and
caudal-most protuberances are bright red
with long, white, exible setae. The dorsolateral
protuberances are white and the dorsal pairs
yellow, with shorter black setae. There is a
canary-yellow saddle mid-body.