Unexpected meal: first record of predation upon a potentially neurotoxic sea slug by the European green crab Carcinus maenas

Abstract

An unexpected predator-prey interaction is reported between two successful invasive species in Patagonia, the European green crab Carcinus maenas (Linnaeus, 1758) and the potentially neurotoxic grey side-gilled sea slug Pleurobranchaea maculata (Quoy & Gaimard, 1832). On two different occasions, a total of four crabs were observed preying upon the sea slugs in the field. The establishment of a novel predator-prey interaction between these species can imply significant effects on their potential spread and invasive success along the South Western Atlantic, as well as it provides a noteworthy contribution towards the knowledge of the currently underexplored question related to what eats the sea slugs.