Colour - Variable, browns, yellows, reds, greens, oranges, often with blotches.
Body - Stout with long hair scales.
Wings - 2 Pairs. Membranous. Hairy
Broad, Wing-span up to 180 mm in some species.
Mouthparts - Much reduced.
Antennae - 3 segments.
pectinate, bipectinate to apex. Feather like.
Legs - Broad overlapping scales. Feet (Tarsi) have 5 segments.
Head - Broad overlapping scales. Large rounded compound eyes.
Proboscis rarely present.
Thorax - Broad overlapping scales. 3 segments. Front segment much smaller. Hairy
Abdomen - Broad overlapping scales. 7-11 segments. Spiracles on segments 1-7. Hairy
Egg - Flat. Smooth. Asymmetrical.
Habits - Can't fly when cold.
Body - Has tufts stiff bristles which will penetrate and irritate the skin if handled. Bristles stick out of stout, silken cocoon case also, providing similar protection. 10-30 mm long, 5-10 mm wide.
Mouthparts - Chewing.
Antennae - Short. 3 segments.
Legs - 5 segments. Single claw on end.
Head - Hard.
Thorax - 10-11 segments. Spiracles on segments 1 to 8. Prolegs on segments 3, 6 and 10
Habits - Feed during day. Herbivorous.
Cocoon - Silken. Has slit or funnel like opening to allow adult to escape easily.