The Hydrangea Sphinx is a relative large caterpillar (almost as large as my thumb) that feeds on plants in the hydrangea family. The caterpillar below was found (Summer 2010) near a mock orange plant (an ornamental Philadelphus species in the family Hydrangeaceae). The caterpillar eggs are laid singly and it is a good thing because a single caterpillar can consume a large amount of foliage. One caterpillar, however, doesn’t make a huge dent in the foliage.
For most of its life, the caterpillar is green. As pupation approaches, the larvae turn the chocolate brown color of the larva pictured. The spiracles on the side of the caterpillar appear in the photo as reddish-orange squares. The spiracles are oval with white coloration at the apogees of the oval, that gives it a “square appearance. Most of the caterpillars in the genus Darapsa have this spiracle coloration.
Adult hawkmoths are important pollinators of flowers including some species of orchid. Some orchid species have special structures, pollinaria, that stick to the bodies of insects that visit the flowers. The hawkmoths are strong fliers and can be observed hovering in flight while feeding on nectar from flowers.