Pachycheles chacei Haig, 1956

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 : 47-50

Pachycheles chacei Haig, 1956

( Figs. 22 , 23 )

Pachycheles chacei Haig 1956: 9 , pl. 1; Haig 1960: 135, pl. 31, fig. 3; Haig 1968: 68; Gore & Abele 1976: 19; Werding 1977: 190, fig. 11; Gore 1982: 8; Rodríguez et al. 2005: 555, pl. 1 fig. D; Lazarus-Agudelo & Cantera-Kintz 2007: 229; Moscoso 2012: 77, fig. 5D; Poupin 2018: 148.

Pachychelis rudis . — Nobili 1901: 18 (part) [not Pachycheles rudis Stimpson, 1858 ].

Material examined. Panama [ Pacific ]: 2 males, cl 4.1, cw 4.6 and cl 3.3, cw 3.4 ( MZUSP 33468 ) , Río Mar , rocky intertidal, low tide, leg. A. Anker, J.F. Lazarus-Agudelo & T. Kaji, 20.03.2015; 2 ov. females, cl 4.3, cw 5.1 and cl 4.1, cw 4.0 ( MZUSP 33477 ) , Río Mar , rocky intertidal, low tide leg. A. Anker, J.F. Lazarus-Agudelo & T. Kaji coll., 20 March 2015, rocky intertidal; 1 ov. female, cl 5.3, cw 6.5 ( MZUSP 33970 ) , Las Perlas Is., Isla Contadora , Playa Cacique, rocky-sandy intertidal, low tide, under rocks and in rock crevices, leg. A. Anker, J. Luque, T. Kaji & A.R. Palmer, 16.04.2014; 1 ov. female, cl 4.1, cw 4.9 ( FLMNH UF 57126 ) , Las Perlas Is., Isla Bartolomé , 8°38’51.8”N, 79°02’17.3”W, rocky intertidal, low tide, insde rock crevices, leg. P.P.G. Pachelle & M. Leray 24.03.2019 (fcn PP 19-082); 1 male, cl 2.8, cw 3.0 ( FLMNH UF 57127 ) , same collection data as for previous specimen (fcn PP 19-083); 1 female, cl 3.5, cw 4.2 ( FLMNH UF 57128 ) , same collection data as for previous specimen (fcn PP 19-084); 1 male, cl 5.5, cw 5.6 ( FLMNH UF 57129 ) , same collection data as for previous specimen (fcn PP 19-097) . Panama [ Caribbean ]: 1 ov. female, cl 4.0, cw 4.7 ( MZUSP 33478 ) , Isla Grande , western point, in coral rocks, depth 0.5–2 m, leg. A. Anker, J.F. Lazarus-Agudelo & T. Kaji, 27.03.2015; 1 male, cl 4.8, cw 5.2, 1 ov. female, cl 4.2, cw 4.8 ( MZUSP 40066 ) , Isla Grande , northern side, large shallow bay, exposed rocky intertidal, in rock crevices, leg. A. Anker et al., 31.07.2018; 1 male, cl 4.5, cw 4.8, 1 ov. female, cl 4.8, cw 5.6 ( MZUSP 33693 ) , between Sabanitas and Portobelo, shallow intertidal flat with adjacent fossilised coral platform with steep drop-off, in coral rocks at wave breaking area, leg. J.F. Lazarus-Agudelo, 25.03.2015 .

Previous records from Panama. Haig (1956, Atlantic); Gore & Abele (1976, Atlantic and Pacific).

Distribution. East Pacific: Guatemala, El Salvador, Costa Rica, Panama ( Isla Verde inside Golfo de Montijo, Río Mar, vicinity of Ciudad de Panamá, Las Perlas Is., Bahía Piña in Darién), Colombia, Ecuador and Peru ( Haig 1960; Gore & Abele 1976; Lazarus-Agudelo & Cantera-Kintz 2007; Moscoso 2012; present study). West Atlantic: Panama (Bocas del Toro, Punta Galeta, Portobelo, Isla Grande, Bahía de Caledonia, Golfo de Darién), Colombia and Venezuela ( Haig 1956, 1960; Gore & Abele 1976; Werding 1977; Rodríguez et al. 2005).

Ecology. Intertidal and shallow subtidal, presently known depth range: 0–7.5 m; typically found on rocky and mixed rocky-sandy shores, dwelling deep in rock crevices ( Haig 1960; present study).

Remarks. Originally described from the western Atlantic (Bahía de Caledonia in Panama), P. chacei is currently regarded as an amphi-American species, with populations well established on both coasts of the Isthmus of Panama ( Haig 1960; Werding 1977). The colour patterns of the Caribbean and eastern Pacific specimens ( Figs. 22 , 23 ) seem to present some variations, e.g. in the background colour ranging from greenish grey to brown, with a more or less pronounced paler dorsal ring, but are generally similar (see Rodríguez et al. 2005 for colour photograph of a Caribbean specimen). Pachycheles chacei is morphologically very close to the western Atlantic P. greeleyi ( Rathbun, 1900) and P. serratus ( Benedict, 1901) , for instance, in the dorsal granulation of the P1 and the dentition on the mesial margin of the P1 carpus. However, the three species can be distinguished by the presence or absence of male pleopods combined with the number of the telson plates, as following: P. chacei has one pair of male pleopods and a five-plated telson; P. greeleyi has no pleopods in males and a telson composed of either five or seven plates; P. serratus has one pair of male pleopods and a seven-plated telson ( Ferreira & Melo 2010, 2016).

Another presumably amphi-American species of Pachycheles , P. monilifer Dana, 1852 , was recorded from Florida ( Fig. 87F ) to southern Brazil in the western Atlantic and from Ecuador and Peru in the eastern Pacific ( Haig 1960; Table 3). It may therefore also occur in Panama, although no specimens have been collected so far on either coast of this country. Miranda et al. (2014) found almost no genetic difference betweent the specimens of P. monilifer from Mexico, Venezuela and Brazil; however, their analysis did not include material from the eastern Pacific.

Figures

FIGURE 22. Pachycheles chacei Haig, 1956:A, B, ovigerous female (cl 4.3 mm, cw 5.1 mm) from Río Mar, Panama (MZUSP 33477), dorsal (A) and ventral (B) views [photographs by AA].

FIGURE 23. Pachycheles chacei Haig, 1956: A, B, ovigerous female (cl 4.0 mm, cw 4.7 mm) from Isla Grande, Panama (MZUSP 33478), dorsal (A) and ventral (B) views [photographs by AA].

FIGURE 87. Some Porcellanidae reported from Colombia (A–E) or with transisthmian distribution (F), likely occurring in Panamanian waters: A, B, Neopisosoma neglectum Werding, 1986, male (A) and female (B) from Saint Martin (FLMNH UF 32006); C, D, Neopisosoma curacaoense (Schmitt, 1924), male (C) and female (D) from Saint Martin (FLMNH UF 32027); E, Neopisosoma bicapillatum Haig, 1960, male from Bahía Málaga, Colombia (CRBM-UV), all in dorsal view [photographs by AA]; F, Pachycheles monilifer Dana, 1852, male from Florida, USA (FLMNH UF 13258), dorsal view [photograph courtesy of Gustav Paulay].