One of many male Automeris io from Wellfleet/Eastham, Cape Cod, MA.
These are also in the Saturnidae family and have no functioning mouthparts. The larvae feed together until the final instar. The females of this species have brown forewings instead of yellow. Automeris is a new world genus. The caterpillars can also give a nasty sting.
Automeris io (Saturniidae - Hemileucinae) is a colorful moth known from the United States and Mexico .
The Io moth adult is 2.0 to 3.5 inches (50 to 87 mm) in wingspan and easily recognized by the large eye-spots of the hindwings. The species is sexually dimorphic, adult males are mostly yellow (top in the photo), while females have brown forewings (bottom in the photo) .