
Appearance
Snout butterflies have prominent elongated mouthparts which, in concert with the antennae, give the appearance of the petiole of a dead leaf. Snouts often take advantage of their brilliant camouflage by hanging upsidedown under a twig, making them nearly invisible.Wings are patterned black-brown with white and orange markings. The fore wings have a distinctive squared off, hook-like tip.
Caterpillars appear humpbacked, having a small head, swollen first and second abdominal segments, and a last abdominal segment that is tapered and rounded. They are dark green with yellow stripes along the top and sides of the body, and have two black tubercles on the top of the thorax.

Migration
Massive migrations of this species often attract attention in the Texas and Mexican newspapers.References:
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