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Charybdis hellerii is an invasive swimming crab widely disseminated in the western Atlantic. This species became a threat to colonized ecosystems, competing with local species for resources. The extension of distribution and increasing population size of C. hellerii has been associated with the scarcity of indigenous predators and cases of predation report octopuses as the main native predators. In this study, we present the first evidence that native fish can consume C. hellerii. 53 individuals of the goldspotted snake eel, Myrichthys ocellatus, were collected at seagrass and macroalgal beds in Pernambuco State, Brazil, and had their stomach contents analyzed. Three juvenile C. hellerii were found along with native prey. Myrichthys ocellatus feeds mainly on small crabs, thus C. hellerii individuals were consumed before reaching sexual maturity. Oppositely to octopuses and other crab predators, M. ocellatus is of little fishing interest and is commonly found in macroalgae beds, seagrass meadows and sandy areas near reefs. Our results suggest that a higher number of carcinophagous taxa may prey on this invasive crab and we emphasize that the conservation of these species is paramount for controlling C. hellerii populations in invaded areas.

IntroductionThe Eudrilidae earthworms are endemic to the Ethiopian region (Reynolds, 1994). They present extreme variations in the sexual apparatus, particularly of the female organs (Omodeo, 2000;Blakemore, 2002. Eudriline evolution has resulted in economy of sperm production. Modifications in the male apparatus appear to reduce, or prevent, gregarine ravages (Sims, 1987). Eudrilus eugeniae has achieved a pantropical distribution (Omodeo, 2000).Megascolecidae is the most diverse family of earthworms (Blakemore, 2002); it has over 1000 species (Sims and Gerard, 1985;Blakemore, 2002). Most of them are native to Asia (Blakemore, 2002) and Australia (Sims and Gerard, 1985). One genus of the family Acanthodrilidae, Diplocardia, is native to North America. Several genera of Megascolecidae sensu stricto [i.e. Arctiostrotus, Argilophilus, Chetcodrilus, Drilochaera, Driloleirus (the only meroic genus), Kincaidodrilus, Macnabodrilus, Nephrallaxis, and Toutellus], placed under the as of yet poorly defined tribe