Rosy maple moth

Description

Rosy maple moth is a common, small, silkworm moth. It occurs in the united States and southern Canada east of the Great Plains. Caterpillars are found feeding on the leaves of hardwood trees, especially red maple, silver maple, and sugar maple, but also boxelder and oak. Adults do not feed.

The adult is 1″ (26 mm) in length and has a wingspan of 1¼″ to 2 3⁄16″ (32 to 55 mm). It is a medium-sized moth but one of the smallest royal silkworm moths.

On males, the antennae are feather-like, with branches on both sides of the central axis (bipectinate). On females, the antennae are thread-like, unbranched.

The color is highly variable. The thorax is densely covered with long hairs that may be bright yellow, pale yellow, cream-colored, or white. The wings are rosy pink except for a broad median area which can also be bright yellow, pale yellow, cream-colored, or white. Sometimes the subterminal area is the same color as the median area. The legs are always rosy pink. A completely white form, called alba, occurs in Missouri.

The mature larvae, called green-striped mapleworm, is pale bluish-green or whitish-green with seven narrow, dark green stripes. On the second segment of the thorax (T2) there are two long black horns. On the abdomen there is a row of short black spines in the dorsal, subdorsal, and subspiracular areas. The subspiracular spines are the longest. There is often a rosy patch below the breathing pores (spiracles) on the seventh and eighth abdominal segments (A7 and A8). The head is beige to orangish-brown.

Size

Total length: 1″ (26 mm)

Wingspan: 1¼″ to 2 3⁄16″ (32 to 55 mm)

Similar Species

Habitat

Deciduous forests, woodlands, and bottomlands

Ecology

Season

One generation per year: May to August.

Behavior

Adults are active at night and will come to lights.

Young caterpillars, in the first three stages (instars), feed in groups. Older caterpillars feed alone.

Life Cycle

The female lays groups of 10 to 30 eggs on leaves of a host tree.

Pupa overwinter in a shallow chamber in the ground.

Larva Food/Hosts

Leaves of mostly maple trees, especially red maple, silver maple, and sugar maple, but also boxelder and oak.

Adult Food

Adults do not feed