Petrolisthes platymerus Haig, 1960

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 : 111

Petrolisthes platymerus Haig, 1960

Petrolisthes platymerus Haig 1960: 108 , pl. 4, pl. 29, fig. 3; Haig 1968: 66; Gore 1972: 336, figs. 1–6; Gore & Abele 1976: 24; Gore 1982: 18; Hiller et al. 2004: 131; Lazarus-Agudelo & Cantera-Kintz 2007: 230.

Petrolisthes eriomerus . — Boone 1931: 154 (part., specimen from Taboguilla) [not Petrolisthes eriomerus Stimpson, 1871 ].

Material examined. None.

Previous records from Panama. Boone (1931, as P. eriomerus Stimpson, 1871 ); Haig (1960); Gore (1972); Gore & Abele (1976).

Distribution. East Pacific: Costa Rica, Panama (Playa Venao, Panama Canal area, Taboga Is., vicinity of Ciudad de Panamá, Las Perlas Is.) and Colombia ( Haig 1960, 1968; Gore & Abele 1976; Hiller et al. 2004).

Ecology. Largely intertidal; under rocks, in tide-pools and in crevices of sabellarid reefs ( Haig 1960; Hiller et al. 2004).

Remarks. Although P. platymerus appears to be fairly common and widespread in Panama, it has not been collected by the second author, probably because of its “small size, detritus-covered carapace, and cryptic habits” that make it “difficult to discern in its usually muddy-flocculent habitat” ( Gore 1982). Petrolisthes platymerus is presumably most closely related to P. schmitti Glassell, 1936 and P. brachycarpus , these three species sharing a pubescent carapace; the front sinuously triangular to trilobate; the dorsal surface of the P1 palm swollen; the lateral margin of the P1 palm crested; and the gape of the P1 fingers with a thick tuft of setae. However, P. platymerus differs from both P. schmitti and P. brachycarpus by the carapace rougher and the P4 merus shorter and broader than in the other species ( Haig 1960). The species may also have some affinities with P. holotrichus , which, however, has a nearly smooth carapace; the P1 palm without a crest on the lateral margin; the gape of the P1 fingers without tuft of setae; and the entire body surface tomentose ( Haig 1960; see also Fig. 59 ).

Figures

FIGURE 59. Petrolisthes jugosus Streets, 1872: male (cl 3.5 mm, cw 3.3 mm) from Isla Grande, Panama (MZUSP 40067), dorsal view [photograph by AA].