Inverted roles: Spider predation upon Neotropical velvet worms (Epiperipatus spp.; Onychophora: Peripatidae)


Predatory behavior
Neotropical invertebrates
spider venom and onychophorans

How to Cite

Franco, R., & Monge-Nájera, J. (2016). Inverted roles: Spider predation upon Neotropical velvet worms (Epiperipatus spp.; Onychophora: Peripatidae). UNED Research Journal, 8(2), 171-173.


 Velvet worms are ancient predators with Cambrian origins that occasionally prey on Ctenid spiders. Here we report the opposite case: wolf spiders (Ctenus spp.) feeding on Epiperipatus spp. in Colombia and Costa Rica. Apparently the worms could not expel their defensive adhesive, and the efficacy of the spider venom suggests that onychophoran nerves and muscles are biochemically equivalent to those of insects.


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