Page 321 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Zygaenidae
DISTRIBUTION Japan, Korean peninsula, Chinese Taipei, and southern China
(Hong Kong)
HABITAT Low to medium-altitude forests
HOST PLANTS Eurya japonica and E. emarginata, and Euonymus japonicus
NOTE Noxious yellow-and-black caterpillar
CONSERVATION STATUS Not evaluated, but very common

ADULT WINGSPAN
1¾–2⅜ in (45–60 mm)
CATERPILLAR LENGTH
1–1 ⁄ in (25–27 mm)
PIDORUS ATRATUS
PIDORUS ATRATUS 319

BUTLER, 1877

Pidorus atratus caterpillars hatch from eggs laid on the host

plant in bark crevices or developing ower buds. As a result, the
larvae are evenly distributed over the food plant rather than on
isolated leaves and often in large numbers. When disturbed, the
caterpillars produce and secrete droplets of cyanide compounds
(mainly linamarin and lotaustralin), which is typical of the Actual size
Chalcosiinae subfamily of moths. This acts as a taste deterrent
against natural predators. Contact with human skin can also

cause a delayed urticating e ect due to breakaway fragments of

irritating hairs. With the larva’s head disguised beneath a eshy

hood, the symmetrical body markings make it di cult to tell the The Pidorus atratus caterpillar is yellow with
front end from the rear, unless the caterpillar is seen in motion. broad, black stripes on the sides and bands
across the cranial and caudal segments. A lighter,
almost gray, stripe runs the length of the dorsal
midline. Single black setae occur on the
There are two generations annually, with caterpillars feeding protuberances within these black zones, while
from April to June and August to September. Pupation occurs those in the dorsal yellow zone bear two setae.
Long, thick, white setae form a sparse fringe
in a silken cocoon on host leaves or branches. The adult moths around the entire body.
have distinctive red heads and a white V-shaped blaze on the
wings at rest, and they are day- yers during July and September.