Phrygiopilus chuacusensis Smalley, 1970

Magalhães, Célio & Wehrtmann, Ingo S., 2025, Taxonomic revision and distribution of the freshwater crabs of the family Pseudothelphusidae (Decapoda, Brachyura) from Guatemala, with the descriptions of two new species and keys to the species of all genera, Zoosystema 47 (26), pp. 581-615 : 591-592

Phrygiopilus chuacusensis Smalley, 1970

( Figs 4D, E; 15)

Phrygiopilus chuacusensis Smalley, 1970: 97 , figs 20-23. — Rodríguez 1982: 88; 2001: 440 (in key). — Villalobos F. 1982: 220 (in list). — Villalobos Hiriart & Álvarez 2008: 297 (in list). — Ng et al. 2008: 176 (in list). — Wehrtmann et al. 2016: 779 (in list). — Acevedo-Alonso & Cumberlidge 2022: 578 (Appendix 2, in list).

Isabellagordonia ( Phrygiopilus) chuacusensis – Pretzmann 1971: 21 (in list); 1972: 93.

TYPE MATERIAL EXAMINED. — Holotype. Guatemala • 1 ♂ (19.9:12.2); Baja Verapaz, stream near summit of Sierra de Chuacús, 96 km by highway north of Guatemala City ; 15°00’N, 90°26’W; [ 2029 m elev.] (see Remarks); 19.VIII.1967; A. E. & I. C. Smalley leg.; USNM 126113 .

Paratypes. Guatemala • 4♂ 6♀; data as in holotype; USNM 126114 • 1 ♂; data as in holotype; TMNH 6090 ,

DISTRIBUTION. — Guatemala ( Baja Verapaz) ( Smalley 1970) ( Fig. 15).

DESCRIPTION OF G1 ( Fig. 4D, E)

Stem moderately sinuous; distal portion markedly curved in laterocephalic direction, compressed in caudocephalic direction, approximately the same width along entire stem in mesocaudal view; caudal margin medianly concave in mesocaudal view, lateral lobe indistinct; cephalic margin slightly convex medianly in mesocaudal view. Marginal plate fused subdistally to caudal surface. Marginal suture on mesial surface, gently following the curvature of the stem, distinctly curved towards lateral side distally in mesial view; row of long and short setae along proximal portion of marginal suture. Marginal process wide, broadly rounded in mesocaudal view, not overreaching mesocaudal margin of apex. Lateral suture incomplete, marked by sulcus along first 3/4 of caudal surface, shallower distally. Mesial process unilobed, broadly subtriangular, directed cephalad. Cephalic process absent. Mesial surface produced into large roughly subtriangular supra-apical process covered with short spines along cephalic, caudal margins and distal portion of laterocephalic surface; patch of spines denser along median portion of cephalic and caudal margins. Supra-apical process with caudal margin moderately widened proximally; cephalic surface barely folded proximally, concave medianly; mesocaudal surface smooth, slightly concave. Supra-apical process slightly longer than wide (ratio width/length roughly 0.8), approximately 0.4 times length of entire stem in mesocaudal view; tip subtriangular, distinctly narrower than median portion. Apex narrow, slit-like and elongated mesolaterally, directed cephalad; lower margin smooth (finely crenulated in some paratypes), upper margin (basal portion of supra-apical process) smooth. Field of apical spines poorly developed, narrow, elongated mesolaterally, directed cephalad, with minute spines nearly concealed by basal portion of supra-apical process and distal margin of cephalic surface of G1.

REMARKS

This species is only known from its type locality in the Sierra de Chuacús, department of Baja Verapaz, Guatemala. The types and only specimens available were collected by A. E. Smalley himself and he stated that the type locality (“stream near summit of Sierra de Chuacús”) would be “ 96 km by highway north of Guatemala City ” at 15°00’N, 90°26’W. These coordinates, however, must be a mistake because, when plotted in a map (Google Earth ®, for instance) they do not match the textual information regarding the distance by road from Guatemala City, since these coordinates are placed both far from any road coming from Guatemala City and approximatelly 30 km SE from Sierra de Chuacús. In an attempt to obtain a roughly approximate location based on Smalley’s (1970) textual information by plotting the road distance ( 96 km) along the highway from Guatemala City towards the Sierra de Chuacús in Google Earth ®, the site could be located around the coordinates 15°10’03.45”N, 90°36’27.46”W, 828 m elev., which is more or less in line with information reported by the author.

Following a preliminary study of the material deposited at the UVGCR, Wehrtmann et al. (2016) listed the species as also occurring in the department of Zacapa. A more detailed examination of the male of lot UVGCR 348 for this study, however, showed that it actually belongs to Ph. ibarrai ( Pretzmann, 1978) because of the subtriangular and bifid mesial lobe of the G1.