Page 426 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Saturniidae
DISTRIBUTION Far southeastern Russia, northeastern China, Korean
Peninsula, and Japan
HABITAT Forests
HOST PLANTS Trees, including oak (Quercus spp.), maple (Acer spp.),
walnut (Juglans spp.), and willow (Salix spp.)
NOTE Giant silkmoth caterpillar that squeaks when disturbed
CONSERVATION STATUS Not evaluated

ADULT WINGSPAN
4¼–5 in (110–130 mm)
CATERPILLAR LENGTH
3⅛ in (80 mm)
RHODINIA FUGAX
RHODINIA FUGAX
424
(BUTLER, 1877)

The Rhodinia fugax moth caterpillar hatches in early spring after
overwintering as an egg on a twig. In the rst instar, it is black

on the dorsum and yellow on the sides, but by the third instar the
colors are reversed. During this period the dorsum has rows of
tubercles studded with curved, black bristles, and the caterpillar
groups with its siblings. In the fourth and fth instars, it becomes

solitary and often hangs motionless beneath a branch, its dark
green ventrum blending with the darkness below, and the
light green dorsum blending with the bright sky above.

The full-grown caterpillars, which are smooth to the touch and
squeak when disturbed, spin a cocoon of green silk, shaped like
a pitcher, with an open top and a small hole in the narrow base.
The moths emerge to mate in the fall, and the females lay their
eggs. There are 11 species of Rhodinia in Japan.

Actual size
The Rhodinia fugax caterpillar is dark green
on the ventrum and pale green on the dorsum,
with twin, rounded points on the dorsal peak
behind the head. A thin, yellow lateral line is
clearly visible. The body is smooth but covered
with tiny, yellow knobs and a line of blue,
bead-like scoli. The spiracles are pale orange,
and the head and feet are green.