Hyposmocoma molluscivora
You're probably used to thinking of caterpillars as creatures that munch on leaves and other plant material—nice, harmless herbivores. Here's one that has a different lifestyle. Hyposmocoma molluscivora is a case-bearing moth, which means that the caterpillar spins a loose 'shell' of silk, which may also incorporate debris from its environment as camouflage or additional protection. This caterpillar crawls about, ignoring all of the plants around it, looking for snails. When it finds one, it spins out more silk, trapping it so it can't escape, and wedges its case against the snail shell. Then it crawls out of its case and pursues the snail as it withdraws into its shell, and dines on terrified escargot.
Rubinoff D, Haines WP (2005) Web-Spinning Caterpillar Stalks Snails. Science 309(5734):575


Becky hates snails and loves caterpillars. Does the Science article contain ordering information?
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