Composition and abundance of porcellanid crabs (Crustacea: Decapoda: Anomura) from rocky bottoms off Vitória Island, southeast coast of Brazil

Abstract

ABSTRACT. This study aimed to describe the species composition and abundance of the porcellanid crabs inhabiting the consolidated sublittoral off an island on the southeastern coast of Brazil. During a sampling program at Vitória Island (23º44'S, 45º01'W), collections were carried out monthly from February 2004 through January 2006. The crabs were hand-caught by SCUBA divers during the daytime. The greatest carapace width (CW) was measured, and the sex and developmental stage were identified for each crab. The specimens were grouped into five demographic categories: juvenile males, adult males, juvenile females, adult females, and ovigerous females. A total of 275 crabs belonging to three genera and six species were obtained. Petrolisthes amoenus (Guérin-Méneville, 1855) and Pachycheles riisei (Stimpson, 1858) were the most abundant species. Most of the demographic classes were represented for both species, except that no adult females of P. riisei were recorded. Among the porcellanids, Pachycheles monilifer (Dana, 1852) was the dominant species; it comprised more than 75% of the total individuals sampled, and showed the highest constancy index for the region. The results obtained in this study provided information regarding the faunal composition and the relative abundance of the species, which will be useful as a reference for other sublittoral consolidated-bottom regions along the southeast Brazilian coast.

New records of caridean shrimps, Lysmata ankeri and L. cf. intermedia, from southeast coast of Brazil

“…The absence of records of these species until the present is likely due to their cryptic habit, as well as to low collection efforts in the rocky subtidal of this region (e.g., Mantelatto et al, 2004aMantelatto et al, , 2004bCobo, 2006;Alves et al, 2011;Alves et al, 2012). However, the possibility remains that these shrimps crossed this biological filter through accidental transport, such as in ballast water, as previously recorded for other species of decapod crustaceans (e.g., Mantelatto & Dias 1999;Alves et al, 2006;Tavares, 2011).…”

Substrate preference by the porcelain crab Pachycheles monilifer (Crustacea, Anomura): the bryozoan Schizoporella errata or the polychaete Phragmatopoma caudata?

“…The collection point on Grande Beach is located in an exposed region in rocky intertidal and on Itaguá Pier is positioned in a protected region with about 3 meters depth. Pachycheles monilifer is abundant in both localities and use these two substrates as shelter or/and food resource (Pinheiro et al, 1997;Micheletti-Flores and NegreirosFransozo, 1999;Alves et al, 2011;2013;Leone and Mantelatto, 2015).…”