Page 551 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Erebidae
DISTRIBUTION Western Europe, east to the Urals, North Africa, and Asia Minor
HABITAT Warm, usually dry woodlands with abundant oak
HOST PLANTS Oak (Quercus spp.), including Pedunculate Oak (Q. robur),
Sessile Oak (Q. petraea), and Downy Oak (Q. pubescens)

NOTE Less smooth Catocala caterpillar, re ecting its knobbly food plants
CONSERVATION STATUS Not evaluated

ADULT WINGSPAN
2⅜–3⅛ in (60–80 mm)
CATERPILLAR LENGTH
2⅛–2 ⁄ in (55–65 mm)
CATOCALA SPONSA
DARK CRIMSON UNDERWING 549

(LINNAEUS, 1767)

The Dark Crimson Underwing caterpillar hatches in April from
a slightly attened, spherical, brown-and-yellow egg that has

overwintered. The larva is fully grown in June. It feeds at night,
when it is most easily found, and conceals itself by day on a
branch or trunk, often in a crevice. The pupa, which like that
of other Catocala species, is covered in a bluish-white bloom,
is formed on the food plant, in a cocoon constructed either
between spun leaves or in a crevice or hollow on a limb.

Compared to Catocala species that feed on willow and poplar,
the Dark Crimson Underwing caterpillar is less smooth in
appearance, with larger warts and humps, re ecting the more

irregular, knobbly appearance of oak twigs and branches. The
caterpillar of C. dilecta, also found on oak in warm forests,
is very similar but lacks the pale patches of C. sponsa. Adult
Dark Crimson Underwings y from late July to mid-October

in one generation.

Actual size
The Dark Crimson Underwing caterpillar is
brown, grayish, or blackish with several whitish
or yellowish patches or bands. It has pairs of
brown or blackish warts along the back and
others along the sides, and a rather large hump
and wart on the eighth segment and another
hump with two warts on the eleventh. It is
sparsely covered with sti , dark hairs.