Pachycheles riisei ( Stimpson, 1859 )

Ferreira, Luciane Augusto De Azevedo & Anker, Arthur, 2021, An annotated and illustrated checklist of the porcelain crabs of Panama (Decapoda: Anomura), Zootaxa 5045 (1), pp. 1-154 : 53

Pachycheles riisei ( Stimpson, 1859)

( Fig. 26 )

Pisosoma riisei Stimpson 1858: 228 [nomen nudum]; Stimpson 1859: 75; Schmitt 1935: 188, fig. 48.

Pachycheles riisei .— Haig 1956: 12; Haig 1962: 182; Werding 1977: 192, fig. 14; Rodríguez et al. 2005: 557; Lira et al. 2012: 22, fig. 2D; Ferreira & Tavares 2017: fig. 1D; Poupin 2018: 148, fig. 145; Ferreira 2019: 62; Mantelatto et al. 2021: 569 , fig. 2F.

Pachycheles riseei (lap. cal.).— Lira et al. 2012: 22, fig. 2D.

Not Pachycheles riisei . — Ferreira & Melo 2016: 183 , 551, fig. 2B (part.) [= Pachycheles meloi Ferreira & Tavares, 2017 ].

Pisosoma glabra Kingsley 1880: 406 , pl. 14, fig. 2.

Material examined. Panama [Caribbean]: 1 male, cl 3.6, cw 4.1 ( MZUSP 40063 ), Bocas del Toro , Isla Colón, Boca del Drago , depth 2 m, from crevices in coral rubble, leg. A. Anker et al., 20– 21.07.2018. Extra-limital material . Mexico [Caribbean]: 1 male, cl cw indet. (UNAM-Sisal), Quintana Roo, Cozumel, 1 km north of Playa Corona , depth less than 1.5 m, underside of rocks, among sponges, leg. A. Anker & J Duarte Gutiérrez, 08.07.2010 (fcn COZ3-040) .

Previous records from Panama. None.

Distribution. West Atlantic: USA (Florida), Mexico, Puerto Rico, N, E and S Lesser Antilles, Belize, Panama (Bocas del Toro), Colombia, Venezuela and Brazil from Ceará and Atol das Rocas to São Paulo ( Haig 1956; Rodríguez et al. 2005; Ferreira & Melo 2016; Ferreira & Tavares 2017; Mantelatto et al. 2021; present study).

Ecology. Intertidal and shallow subtidal, presently known depth range: 0–6 m, but possibly deeper (at least 20 m); on rocky shores and coral reefs, under rocks and coral rubble and in crevices of coral rocks, among calcareous algae, sponges, etc. ( Werding 1977; Ferreira & Melo 2016; present study).

Remarks. Although P. riisei is widespread in the western Atantic Ocean, its records are relative scarce. The Bocas del Toro specimen is the first record of the species from Panama, whereas the Cozumel specimen appears to be the first record for Mexico. In the Caribbean Sea, P. riisei can be easily distinguished from other species of the genus by its striking carmin-red colour pattern ( Fig. 26 ; see also in situ photograph in Poupin 2018), which is essentially identical to that of P. biocellatus , its presumed eastern Pacific sister species. In Brazil, P. riisei is relatively common on mainland coasts and some oceanic islands, being replaced by the very similar P. meloi in the remote Trindade e Martin Vaz Archipelago ( Ferreira & Tavares 2017).

Figures

FIGURE 26. Pachycheles riisei Faxon, 1893: A, male (cl 3.6, cw 4.1) from Bocas del Toro, Panama (MZUSP 40063), dorsal view; B, extra-limital specimen, male (cl cw indet.) from Cozumel, Mexico (UNAM-Sisal), dorsal view [photographs by AA].