The larvae of Madoryx pseudothyreus (Lepidoptera: Sphingidae), resident on Adams Key and Elliott Key, Florida, feed on the foliage of black mangrove trees, Avicennia germinans (Avicenniaceae), and pupate in silk cocoons spun on the branches or living leaves of the host. The last instar larva is normally cryptically colored brown and gray, but displays a pair of large eyespots on the thorax and bright colors on the prolegs when disturbed. The pupa bears a bifurcate cremaster that helps to anchor it in the cocoon.
