Biology, distribution, and abundance of Allopetrolisthes punctatus (Guerin, 1835) (Decapoda, Anomura, Porcellanidae), in the rocky subtidal of Chome, central Chile

The porcellanid crabs are diverse and abundant species inhabiting the intertidal and subtidal rocky substrate. One particular species is Allopetrolisthes punctatus, a medium-sized crab, poorly studied but strikingly abundant in some places of Chile. Near Chome (central Chile) large aggregations have been reported by local fishermen. A direct population assessment with semi-autonomous scuba diving was performed to evaluate stock structure, distribution, and abundance. A monthly monitoring was established to analyze the temporal variability of biological traits during a one-year time period. Dense crab aggregations were observed over the naked unprotected rocky substrate, with corporal size and sexual proportion spatially segregated. Allopetrolisthes punctatus showed a relatively high fecundity (164-8,741 eggs) and uninterrupted yearly spawning, which seems to favor the quick and successful settlement for this species in Chome.