Pagurus rotundimanus Wass, 1963

Lemaitre, Rafael & Tavares, Marcos, 2015, New taxonomic and distributional information on hermit crabs (Crustacea: Anomura: Paguroidea) from the Gulf of Mexico, Caribbean Sea, and Atlantic coast of South America, Zootaxa 3994 (4), pp. 451-506 : 493-496

Pagurus rotundimanus Wass, 1963

( Figs. 21 , 22 )

Pagurus rotundimanus Wass, 1963: 149 , fig. 8 (type locality: Dry Tortugas, R/V Oregon, sta 1005, 24°20' N, 83°20' W).— Pequegnat, 1983: 121, fig. 66.— Lemaitre & Cruz Castaño, 2004: 77.—Felder et al., 2009: 1071.— McLaughlin et al., 2010: 34.

Type material. Gulf of Mexico: holotype male 4.0 mm, off Florida, R/V Oregon, sta 1005, 24°20’N, 83°20’W, 347 m, 13 Apr 1954 ( USNM 97466). Paratypes, Florida Keys: 1 ov female 2.7 mm, Florida Keys, sta 68, [no depth data], 1 Aug 1932, coll. W. L. Schmitt ( USNM 103425); 1 ov female 3.7 mm, Florida Keys, sta 30–32, 247 m, 2 Jul 1932, coll. W.L. Schmitt ( USNM 103426); 2 males 3.7, 3.8 mm, 2 females 2.8, 4.2 mm, 1 ov female 3.3 mm, Florida Keys, sta 67, 256– 360 m, 1 Aug 1932, coll. W.L. Schmitt ( USNM 103431); 1 female 3.5 mm, 1 ov female 3.6 mm, Florida Keys, 17.5 miles S of no. 2 red buoy, Tortugas Expedition Carnegie Lab, sta 32–31, 280– 289 m, 22 Jul 1931, coll. W.L. Schmitt ( USNM 103436); 1 male 3.4 mm, Florida Keys, about 18 miles due S of no. 2 red buoy, Tortugas Expedition Carnegie Lab, sta 18–31, 375– 404 m, 3 Jul 1931, coll. W.L. Schmitt ( USNM 107820).

New material. Gulf of Mexico. Off Florida, R/V Citation IV, sta, E1A, 28°54’22”N, 86°24’24W,BLM/MMS, NGOMCS/ 4503, 351 m, 14 May 1985, coll. LGL Ecological Research Associates: 1 male 2.4 mm ( USNM 265248); off Florida, R/V Citation IV, sta E2A, 28°35’01”N, 86°45’44”W, BLM/MMS, NGOMCS/ 4502, 625 m, 13 May 1985, coll. LGL Ecological Research Associates: 2 males 2.4, 2.5 mm, 1 female 2.1 mm ( USNM 265252); off Florida, R/V Citation IV, sta E01, 28°28’47”N, 86°02’32”W, BLM/MMS, NGOMCS/4504, 351– 357 m, 14 May 1985, coll. LGL Ecological Research Associates: 2 males 2.1, 3.1 mm, 3 females 3.6–4.5 mm ( USNM 265249); off Florida, R/V Citation IV, sta E2B, 28°18’58”N, 86°18’56”W, BLM/MMS, NGOMCS/4511, 600– 625 m, 17 May 1985, coll. LGL Ecological Research Associates: 2 females 2.5, 2.8 mm ( USNM 265251); off Florida, R/V Citation IV, sta E2D, 28°07’38”N, 85°51’36”W, BLM/MMS, NGOMCS/4508, 624– 631 m, 16 May 1985, coll. LGL Ecological Research Associates: 1 male 1.9 mm ( USNM 265253); off Louisiana, R/V Citation V, sta WC–1, 27°42’58”N, 92°52’05”W, BLM/MMS, NGOMCS/5501, 344– 393 m, 7 Jun 1985, coll. LGL Ecological Research Associates: 2 females 2.1, 3.0 mm, 2 ov females 2.1, 2.8 mm ( USNM 265254); off Louisiana, R/V Gyre II, sta W01, 27°37’00”N, 93°33’36”W, BLM/MMS, NGOMCS/ 2022, 342 m, 4 Apr 198, coll. LGL Ecological Research Associates: 1 male 3.4 mm, 1 female 3.1 mm ( USNM 265250); 25°55’08”N, 96°25’43”W, 311–384 m, 13 Jun 1989, coll. M. Wicksten: 1 male 3.1 mm ( USNM 259393).

Caribbean Sea. ESE of Cabo Gracias a Dios, coast of Nicaragua-Honduras, R/V Pillsbury, sta 1355, 14°40’N, 81°33’W, 440–797 m, 31 Jan 1971: 1 female 2.0 mm ( USNM 1238335); Colombia, B/I Ancón, sta EA 268, 8°59’24.8”N – 8°59’30.2”N, 76°45’42.8”W - 76°46’27.6”W, 500 m, 6 Jun 2008, coll. INVEMAR: 1 male 3.4 mm ( USNM 1238334).

Diagnosis. Shield ( Fig. 21 A) about as long as broad or slightly broader than long, naked or with scattered short setae; lateral projections terminating in small spine; rostrum broadly triangular, rounded. Ocular peduncles about 0.7 times as long as shield, with few short setae dorsally; cornea dilated; acicles subtriangular, each terminating in simple subterminal spine. Antennular peduncles exceeding distal margin of cornea by nearly full length of ultimate segment, with scattered short setae. Antennal peduncle exceeding distal margin of cornea by one-third length of fifth segment; second segment with distolateral angle produced and terminating strong spine; acicle reaching to or slightly exceeding distal margin of cornea, terminating in sharp spine, unarmed except for setae on mesial margin; flagellum with scattered short setae ≤ 1 article in length. Third maxilliped ischium ( Fig. 21 B) with simple or bifid accessory tooth. Chelipeds ( Fig. 21 C, D) markedly dissimilar in strength; tip of fingers of left reaching to about midlength of fingers of right. Right cheliped with dense, fine setae on dorsal surfaces of chela and carpus; fingers straight, distinctly shorter than palm, cutting edges each with 5 or 6 subequal, large calcareous teeth; chela mostly smooth except for dorsomesial row of small spines or tubercles; carpus smooth except for dorsomesial row of weak (Fig.) or strong spines. Left cheliped moderately covered with setae; fingers about 1.5 times as long as palm and terminating in small inwardly curved corneous claw; chela with elevated dorsomedian ridge armed with row of small spines; carpus with dorsomesial and dorsolateral rows of small spines, and 2 small spines on dorsodistal margin laterally. Ambulatory legs ( Fig. 22 A–D) slender; dactyl long, about 1.8 times as long as propodus, unarmed except for row of long setae on nearly entire dorsal margin, and ventromesial row of long setae on distal half; meri, carpi and propodi unarmed except for short setae on dorsal margins, small dorsodistal spine on each carpus, and 2 or 3 small spines distally on ventral margin of merus of first ambulatory leg (second pereopod). Fourth pereopod ( Fig. 22 E) semichelate, propodal rasp consisting of single row of ovate scales; lacking preungual process. Anterior lobe of sternite XII ( Fig. 21 E) subsemicircular. Uropods markedly asymmetrical. Telson ( Fig. 21 F) nearly symmetrical, 1.5 times as long as broad, with prominent U-shaped median cleft separating posterior lobes; terminal margins of posterior lobes each with row of about 5–11 unequal blunt to sharp spines increasing in strength distally (2 or 3 most distal spines usually largest and ventrally curved).

Distribution. Western Atlantic: Gulf of Mexico, Bahamas, and Caribbean, from off Nicaragua-Honduras border to Colombia. Depth: 247 to 631 m.

Color. Based on Wass (1963: 151, fig. 8): ambulatory legs each with light red band medially on merus and propodus, and right cheliped with light red band distally on merus and proximally on carpus.

Remarks. This rare species had not been mentioned in the literature since its original description by Wass (1963) from the Dry Tortugas, Florida, until Felder et al. (2009) updated its distribution in the Gulf of Mexico. The specimens reported herein of Pagurus rotundimanus in the southwest and southern Caribbean, significantly expands the distribution of this species both horizontally and vertically.

Figures

FIGURE 21. Pagurus rotundimanus Wass, 1963: male 3.4 mm, Colombia, B / I Ancón, sta EA 268 (USNM 1238334). A, shield and cephalic appendages, dorsal; B, ischium of left third maxilliped, outer view; C, right cheliped, dorsal; D, left cheliped, dorsal; E, sternite XII, ventral; F, telson, dorsal. Scales: 1 mm (A, C, D), 0.5 mm (B, E, F).

FIGURE 22. Pagurus rotundimanus Wass, 1963: male 3.4 mm, Colombia, B / I Ancón, sta EA 268 (USNM 1238334). A, left second pereopod, lateral; B, dactyl of same, mesial; C, left third pereopod, lateral; D, dactyl of same, mesial; E, propodus and dactyl of left fourth pereopod, lateral. Scales: 1 mm (A – D), 0.5 mm (E).