Proleg

Anatomical structure

A proleg is a small, fleshy, stub structure found on the ventral surface of the abdomen of most larval forms of insects of the order Lepidoptera, though they can also be found on larvae of insects such as sawflies. In all the orders in which they appear, mainly Hymenoptera and Lepidoptera, prolegs of any form evolved independently of each other by convergent evolution. They appear to have evolved from ancient inactive genes that have since been activated again.

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