4″ Viper headed hissing larva/caterpillar? Found in N. E. Pa on trunk of Red Maple tree. Hisses and strikes like snake when provoked, fake eyes on top, reddish legs… seem to remember 3 or four sets on front… then none til the back. (PA)
Your neat colored caterpillar is the Abbott’s sphinx caterpillar.
These are found in eastern and central North America in and around woodlands that have wild grapevines. The larvae feed on grape foliage and related species of plants.
This cool caterpillar starts out green with a horn or tail on the back-end. Middle stage (instar) caterpillars are whitish to blue-green with dark faint cross-stripes and the horn is replaced by an orange raised knob.
The last instars may be either brown with a “wood-grain” coloration or brown with ten green saddles on the back. In these late instars like yours, the knob resembles an eye.
Such a cool find…thanks for sharing!