Nematopaguroides fagei Forest & de Saint Laurent, 1968

Lemaitre, Rafael, 2020, New and rare micro-pagurid hermit crabs (Crustacea: Anomura: Paguridae) from the Caribbean Sea and Gulf of Mexico, Zootaxa 4722 (4), pp. 301-325 : 308-311

Nematopaguroides fagei Forest & de Saint Laurent, 1968

( Figs 5 , 6 )

Nematopaguroides fagei Forest & de Saint Laurent, 1968: 157 , figs 136–141 (type locality: off Recife, Brazil, Calypso, sta 27, 8°25.5’S, 34°48.5’W); Coelho & Ramos, 1973: 166 (list); Coelho & Santos, 1980: 143 (list); Coelho & Ramos-Porto, 1986: 43 (list); Rieger, 1998: 417 (list); Wang & McLaughlin, 2000: 956; McLaughlin, 2003: 124; McLaughlin et al., 2010: 31; Lemaitre & Tavares, 2015: 492; Coelho et al., 2007: 10, tab. 4; Lemaitre et al., 2017: 164.

Nematopaguroides cf. fagei .— Baker et al., 1981: 355, tab. G4; Felder et al., 2009: 1070 (in part, see Remarks).

Not Nematopaguroides cf. fagei (= N. karukera Lemaitre, Felder & Poupin, 2017 ).— Gore, 1981: 159.

Material examined. Gulf of Mexico: 1 male 1.2 mm, 1 ovig female 1.1 mm, EPA DYNACORP PROJECT, EPA 54763 264-repA, South Marsh Island 57C, platform #2, [south of Grand Isle, Louisiana], 40 m, [no date], coll R .W. Heard ( USNM 1253305 ); 1 male 1.5 mm, R / V Pelican, NSF-II-060, DEB-0315995, 21°34.18’N, 91°4.71’W, 33 m, sand/rubble, box dredge, 12 Jun 2005, coll D.L. Felder et al. ( USNM 1541790 , ex ULLZ 6992 ); 1 male 0.8 mm, R / V Pelican, station NSF-II-098, southwest Gulf of Mexico, 22˚6.91’ N 91˚20.74’ W, 42– 41 m, 17 Jun 2005, gear box dredge, rubble, coll D.L. Felder et al. ( USNM 14655083 , ex ULLZ 7072 ) .

Guadeloupe, French Antilles, Caribbean Sea: KARUBENTHOS 2012: 2 ov females 1.0, 1.1 mm, GS 10, 16°03.25’N, 61°46.17’W, 23 m, 9 May 2012 , vieux habitant-herbier à Halophila stipulacea , MNHN-IU-2013- 5469; female 0.6 mm, GD 11, 16°07.72’N, 61°46.26’W, 14 m, 9 May 2012 anse à la barque-herbier à Halophila stipulacea (MNHN-IU-2013-5613); 1 male 1.0 mm, 1 ov female 1.1 mm (MNHN-IU-2013-5607), 2 males 1.2, 1.5 mm (MNHN-IU-2013-5308), GD 21, Pointe sur baie de Baille-Argent, 16°15.55’N, 61°48.8’W, 40 m, 12 May 2012.

Recognition characters. Shield ( Fig. 5A ) as broad as long, dorsal surface smooth. Rostrum broadly rounded. Ocular peduncles shorter than shield length, dorsal surface with short, stiff setae, corneas weakly dilated; acicles terminating bluntly and with small submarginal spines. Chelipeds ( Fig. 5B, C ) sparsely setose, not much different in length, right stouter, fingers of left reaching to approximately midline of fingers of right; palm of right cheliped with dorsolateral and dorsomesial margins armed with row of small spines; carpi of right and left with distinct dorsolateral and dorsomesial row of spines. Pereopods 2 and 3 ( Fig. 6 A–D) with long setae mostly on dorsal and ventral margins; dactyls broadly curved, approximately 1.1 times as long as propodus, with ventromesial row of 3–6 slender corneous spinules. Propodal rasp of pereopod 4 ( Fig. 6E ) with single row of rounded scales. Telson ( Fig. 6F ) posterior lobes asymmetrical, separated by deep median U-shaped cleft, terminal margins each armed with 2 or 3 spines in addition to more prominent ventrally curved spine at lateral angle. Male with unpaired right sexual tube on coxa of fifth pereopod ( Fig. 5D ), tube coiled and distally filiform. Ovigerous female carrying relatively few (usually 10–15) eggs.

Color. Unknown.

Distribution. Gulf of Mexico, from Louisiana and off Yucatán; Caribbean Sea Lesser Antilles, from Guadeloupe; and States of Pernambuco and Bahia, Brazil. Depth: 14– 41 m.

Remarks. This is the type species of Nematopaguroides Forest & de Saint Laurent, 1968 . Since Forest & de Saint Laurent’s (1968) description of N. fagei , this rare species has been mentioned in biogeographical studies of the decapod fauna from Brazil ( Coelho & Ramos 1973; Coelho & Santos 1980; Coelho & Ramos-Porto 1986; Coelho et al. 2007), although apparently no new material was collected in those studies and thus the distribution was based on the few type specimens from Pernambuco to Bahia, Brazil. Gore (1981) did report one juvenile from Key Largo, Florida, noting that because of its small size and juvenile condition could not be positively identified as this species, and thus was reported therein as N. cf. fagei . However, examination of Gore’s material (formerly in the Indian River Coastal Zone Museum, HBOI 89:4699, currently under Florida Atlantic University oversight) has shown that it is an adult albeit minute male (shield length = 1.1 mm) of N. karukera Lemaitre, Felder & Poupin, 2017 .

Felder et al. (2009) tentatively included Nematopaguroides fagei (as N. cf. fagei ) in the fauna from the Gulf of Mexico based on the equally tentative report by Gore (1981) but cited additional specimens they collected in the northwestern Gulf of Mexico (cited in Baker et al. 1981). Felder et al. questioned whether the specimens from the Gulf actually represent N. fagei , a species until then known only from Brazil. However, a male and an ovigerous specimens (USNM 1253305) collected south of Grand Isle, Louisiana, have been studied and agree in most respects with Forest & de Saint Laurent’s (1968) description of Nematopaguroides fagei , except that the Louisiana specimens have a right chela with a dorsal surface smooth, unarmed and nearly glabrous, whereas Forest & de Saint Laurent describe a right chela with dorsolateral, dorsomesial and medial rows of spines. This difference in armature may well represent intra-specific morphological variation of the type frequently seen on the right cheliped in other pagurids (e.g., Lemaitre et al. 1982). The morphology of two male specimens (USNM 1541790 ex ULLZ 6992, USNM 14655083, ex ULLZ 7072) collected in the southwest Gulf of Mexico, although the former is missing the ambulatory legs, and the latter is small in size (shield length = 0.8 mm), is consistent with the definition of N. fagei by Forest & de Saint Laurent (1968).

Nematopaguroides fagei can be differentiated from the other two western Atlantic congeners (i.e., N. pusillus and N. karukera ) by the armature of the carpus of the left cheliped (with a dorsolateral and dorsomesial row of spines on the carpus in N. fagei vs. with few weak spines or spineless in N. pusillus and N. karukera ), and the shape and proportions of the dactyls of pereopods 2 and 3 (long and broadly curved in N. fagei vs. short and curved in N. pusillus and long and straight in N. karukera ).

The specimens of N. fagei herein reported indicate a considerable range for this species, from the Gulf of Mexico and Caribbean Sea Lesser Antilles to Brazil. Based on the morphology of the few known specimens alone, and until more material can be collected throughout a broad geographic range to be analyzed using both comparative anatomy and DNA techniques, no other conclusion than this species having a broad distribution can be reached.

Figures

FIGURE 5. Nematopaguroides fagei Forest & de Saint Laurent, 1968, male 1.5 mm, KARUBENTHOS 2012, sta GD 21, Pointe sur baie de Baille-Argent, Guadeloupe, French Antilles, Caribbean Sea (MNHN-IU-2013-5308): A, shield and cephalic appendages, dorsal; B, right cheliped, dorsal; C, left cheliped, dorsal; D, sternum, coxae of pereopods 1–5, and sexual tube, ventral. Scale: 0.5 mm.

FIGURE 6. Nematopaguroides fagei Forest & de Saint Laurent, 1968, male 1.5 mm, KARUBENTHOS 2012, sta GD 21, Pointe sur baie de Baille-Argent, Guadeloupe, French Antilles, Caribbean Sea (MNHN-IU-2013-5308): A, left pereopod 2, lateral; B, dactyl of same, mesial; C, left pereopod 3, lateral; D, dactyl of same, mesial; E, propodus and dactyl of left pereopod 4, lateral; F, telson, dorsal. Scale: 0.5 mm.