Munidopsis shulerae, Vázquez-Bader, Ana Rosa, Gracia, Adolfo & Lemaitre, Rafael, 2014

Vázquez-Bader, Ana Rosa, Gracia, Adolfo & Lemaitre, Rafael, 2014, A new species of Munidopsis Whiteaves, 1874 (Crustacea: Anomura: Galatheoidea: Munidopsidae) from the Gulf of Mexico and Caribbean Sea, Zootaxa 3821 (3), pp. 354-362 : 355-360

Munidopsis shulerae sp. nov.

( Figs 1 , 2 )

Type material. Holotype, female [P5 missing], CL 10.4 mm, SW Gulf of Mexico, NW of Alacranes Reef, BIOREPES2, R/V Justo Sierra, sta 31, 22°41'63''N, 90°45'14''W, 639.9-642.1 m, 0 6 June 2007, coll. AGG, EPC 312007.

Paratypes: NE Gulf of Mexico, off Florida: 2 males (CL 8.6 mm, 9.4 mm), 1 female (CL 10.0 mm), NGOMCS, R/V Citation, cruise IV, sta E2B, MMS-GOMCS/4511, 28°18’58”N, 86°18’56”W, 600–625 m, 17 May 1985, coll. LGL, USNM 1227847; 1 male (CL 3.9 mm), 1 ovig. female (CL 6.3 mm), MMS-NGOMCS, R/V Citation, cruise IV, sta E1B, MMS-NGOMCS/4505, 28°18’40”N, 85°44’20”W, 344–346 m, 15 May 1985, coll. LGL, USNM 1227848; 1 male (CL 10.3 mm), R/ V Citation, cruise IV, sta E2C, MMS-NGOMCS/4509, 28°13’33”N, 86°06’39”W, 616–620 m, 17 May 1985, coll. LGL, USNM 1227851; 3 male (CL 6.0– 7.8 mm), 1 ovig. female (CL 11.5 mm), R/V Citation, cruise IV, sta E2D, MMS-NGOMCS/4508, 28°07’38”N, 85°51’36”W, 624–631 m, 16 May 1985, coll. LGL, USNM 1227850; 1 male (CL 7.8 mm), R/V Citation, cruise IV, sta E2E, MMS-NGOMCS/4507, 28°01’04”N, 85°39’38”W, 629 m, 16 May 1985, coll. LGL, USNM 1227849; NW Gulf of Mexico, off Louisiana: 1 male (CL 7.0 mm), R/V Citation, cruise V, sta WC-4, MMS-NGOMCS/5505, 27°43’10”N, 92°09’14”W, 516–527 m, 10 June 1985, coll. LGL, USNM 1227852; 1 male (CL 5.5 mm), R/V Citation, sta WC-6, MMS-NGOMCS/5506, 27°42’44”N, 91°32’55”W, 543 m, 10 June 1985, coll. LGL, USNM 251462; SW Gulf of Mexico, off Campeche: 1 male (CL 6.8 mm), BATO, R/V Justo Sierra, sta 15, 22°23’41’’N, 91°37’88’’W, 603 m, 24 May 1988, coll. AGG, EPC 151998; 1 female (CL 7.9 mm), BIOREPES2, R/V Justo Sierra, sta 25, 22°41’63’'N, 90°4577'W, 640-643 m, 0 6 June 2007, coll. AGG, EPC 252007; 1 male (CL 10.5), SW Gulf of Mexico, off Yucatan: BIOREPES1, R/V Justo Sierra, sta 55, 23°55’50’’W, 645.2–649.0 m, 14 August 2005, coll. AGG, EPC 552005.

Non-paratypes. The following material used by Mayo (1974) has not been located at the USNM or UMML, and is presumed lost: western Caribbean, off Yucatan, 1 male (CL 7.4 mm), R/V Pillsbury, sta 607, 18°30’N, 87°37’W, 715–787 m, 17–18 March 1968; 1 female (CL 8.1 mm); 1 ovig. female (CL 7.0 mm), Straits of Florida, R/V Gerda , sta 160, 26°33’N, 79°42’W, 320–586 m, 26 June 1963.

Description. Carapace ( Fig. 1 A, D, E): Quadrangular, 1.1–1.2 as long as broad, lateral margins subparallel. Dorsal surface nearly flat in lateral view except for broad, deep groove separating gastric and cardiac regions, unarmed except for coarse cover of small simple or minutely multidentate tubercles. Regions well delineated by deep grooves or furrows, gastric region inflated. Frontal margin behind ocular peduncles oblique, with small but conspicuous blunt submarginal protuberance between antennal and ocular peduncles. Epigastric region divided into two distinctly inflated processes, each delimited anteriorly by semicircular, tuberculated ridge. Gastric region separated from hepatic and branchial regions by anterolateral and posterior branches of cervical groove. Meso- and metagastric regions less inflated than epigastric region, with small tubercles. Posterior cardiac region triangular, elevated, with scattered, small, unequal tubercles, and preceded by deep, long transverse furrow. Metabranchial region not inflated, with small tubercles. Antennal spine absent. Lateral margins nearly straight, subparallel, with small or minutely multidentate tubercles; hepatic region bluntly subtriangular, separated from adjacent regions by well-defined furrow. Posterior margin preceded by elevated, transverse, sharp ridge. Pterygostomian flap ( Fig. 1 E, 2A) covered with well-spaced, minutely multidentate tubercles; anterior half with deep, large depression, anterior margin bluntly subtriangular. Rostrum ( Fig. 1 A, D–G) short, about 0.25 length of remaining carapace, slender, subtriangular in cross-section, nearly horizontal in lateral view, terminating in blunt tip; dorsal surface with median carina extending nearly to epigastric region and continued as small row of tubercles between inflated portions of epigastric region; surfaces lateral to carina smooth or minutely tuberculate.

Sternum ( Fig. 1 B): Sternum almost as long as broad, maximum width at sternites 6 and 7; sternites smooth except for small granules on anterior portion and distal margin of sternite 4. Sternite 3 (basal to third maxillipeds; Fig. 2 B) with anterior and posterior margins sinuous, subdivided into lobes by anteromedian notch; anterior margin denticulate. Sternite 4 with subcircular median depression distally near posteromedian margin of sternite 3.

Pleon ( Figs. 1 A, 2A): Pleon lacking spines, surfaces of tergites and pleura smooth except sometimes few small tubercles on pleuron of second somite. Tergite 2–4 with raised, transverse rim anteriorly, tergites 5 and 6 lacking rim. Telson ( Fig. 1 C) about 1.2 times as broad as long, composed of 8 plates. Uropods smooth; endopod subtriangular, with long setae on lateral and posterior margins, dorsal surface with weak submedian longitudinal carina extending from proximal margin to distal 0.75 of endopod; exopod subtriangular, with long setae on anterior and lateral margins, dorsal surface with weak carina close to and parallel to anterior margin and extending form proximal margin to distal 0.75 of exopod. Protopod unarmed.

Eye ( Fig. 1 A, D–G): Ocular peduncle short, stout, movable, unarmed. Cornea subglobular, weakly pigmented, at most reaching level of midline of second antennal segment.

Antennule ( Fig. 1 F, 2C): Basal article armed with 2 strong, conspicuous, well separated spines (often with multifid tip): 1 ventrodistal spine directed anteriorly, at most reaching to tip of rostrum, and 1 dorsodistal spine directed anterodorsally. Flagellum long, slightly more than 0.2 times longer than CL.

Antenna ( Fig. 1 D, 2C): Basal segment of peduncle not exceeding rostrum, with ventromesial projection; segments 1–3 unarmed; segment 4 with distal dorsolateral lobe.

Maxilliped 3 ( Fig. 2 D): Ischium longer than broad; extensor margin sharply ridged, with distolateral spine, crista dentata with 17–23 sharp or blunt corneous denticles; merus with 2 or 3 distinct, usually unequal spines on flexor margin, with distalmost spine usually shortest, extensor margin weakly serrated and terminating in small spine; carpus, propodus, and dactyl unarmed.

Pereopod 1 (cheliped) ( Fig. 2 E): Surfaces covered with numerous, well-spaced minute granules or tubercles, sparsely setose. Carpus and chela slightly flattened dorsoventrally. Major cheliped 2.7–3.6 times, and minor about 3.0 times, as long as carapace. Merus with concave mesial surface. Palm about 1.3 length of carpus. Fingers not gaping when closed, or only slightly gaping proximally; cutting edges of fixed finger and dactyl each with row of small, blunt subtriangular teeth, and row of setae on each side, dactyl with large, rounded tooth proximally.

Pereopods 2–4 (walking legs) ( Fig. 2 F–H): P2 to P4 similar in shape and ornamentation, moderately slender, long, lacking spines, surfaces with numerous minute tubercles, sparsely setose; meri each with minute, well-spaced tubercles mostly on proximal half of lateral surface; carpi, propodi and dactyls mostly smooth. P2 and P3 subequal in size, P4 shortest. Carpus with weak longitudinal dorsolateral ridge. Dactyl broadly curved, terminating in long, sharp, slender corneous claw.

Epipods: absent from all pereopods.

Etymology. This species is named to honor Dr. Barbara Shuler Mayo (1945–1988), using her maiden name, and who first recognized but never formalized the description of this new species. The name is in recognition of her outstanding work on western Atlantic species of Munidopsis , much of which unfortunately remained unpublished after her untimely death ( The Boston Globe 1988).

Colour. Overall whitish.

Distribution. Known from the northern and southwestern Gulf of Mexico, the Straits of Florida, off coast of Campeche, and the western Caribbean off the Mexican coast of Yucatan. Depth: 320 to 787 m.

Remarks. As previously mentioned, Mayo (1974) was the first to recognize this new species in her unpublished doctoral dissertation. Regrettably, Mayo never published a description before, and her dissertation does not meet the Code’s criteria for publication (art. 8, ICZN 1999). Therefore, the name she used, which to our knowledge has never been mentioned in any capacity in any publication, is unavailable. Mayo’s specimens of this new species, one male and one female from R/V Pillsbury station 607, off Yucatan, presumably deposited in USNM, and one ovigerous female from R/V Gerda station 160, in the Straits of Florida, presumably deposited in UMML, have not been found and are considered lost.

Munidopsis shulerae sp. nov. is most similar to a western Atlantic congener, M. polita ( Smith, 1883) , in the shape and size of the rostrum as well as presence of a dorsal, longitudinal carina, a carapace with well delimited regions, and general shape and size of all pereopods. The two can be distinguished based on the following characters: the carapace regions are better delimited and are more inflated ( Fig. 1 A, D) in the new species than in M. polita ( Fig. 3 A–C); the rostrum of the new species is horizontal ( Fig. 1 E), directed straight ahead, and has a distinct, tuberculate, dorsal carina that extends into the epigastric region, whereas in M. polita the rostrum ( Fig. 3 D) is oblique, directed downwards, and the dorsal carina does not extend to the epigastric region; the dorsal ornamentation of the carapace is coarser, with larger and more numerous tubercles in the new species ( Fig. 1 A, D) than in M. polita ( Fig. 3 A, B, D); in the new species there is a conspicuous, blunt, submarginal protuberance between the antennal and ocular peduncles ( Fig. 1 F), whereas in M. polita there is no such protuberance ( Fig. 3 B, C); and in the new species, sternite 3 is divided into narrrow, ovate lobes with sinuous anterior and posterior margins ( Fig. 2 B), whereas in M. polita , sternite 3 is divided into subcircular lobes ( Fig. 3 E).

Of the seven groups of Munidopsis species recognized by Ahyong et al. (2011), M. shulerae sp. nov. can be assigned to the Anoplonotus group, which includes species characterized by having a simple, narrow rostrum, lacking eye spines, carapace with regions well marked, fused sternites 3 and 4, pleonal tergites unarmed dorsally, and dactyls of walking legs falcate and with smooth flexor margins. Ahyong et al. (2011) included six species in this group: M. polita , M. bruta Macpherson, 2007 , M. granulata Miyake & Baba, 1967 , M. palmatus Khodkina, 1973 , M. truculenta Macpherson & Segonzac, 2005 , and M. vesper Taylor et al., 2010 . Of these, only M. polita occurs in the western Atlantic, whereas the remainder are distributed in the Pacific or Indian Ocean, or the eastern Atlantic. Munidopsis shulerae sp. nov. is clearly distinguished from all others in the Anoplonotus group by the presence in this new species of a dorsal, longitudinal carina on the rostrum that extends to the epigastric region, and a conspicuous submarginal protuberance between the antennal and ocular peduncles.

Figures

FIGURE 1. Munidopsis shulerae sp. nov. A – C, holotype, female (CL 10.4 mm), SW Gulf of Mexico, NW of Alacranes Reef, EPC 312007; D – G, paratype, female (CL 10.0 mm), NE Gulf of Mexico, off Florida, USNM 1227847. A, carapace and pleonites 1 – 3, dorsal; B, sternum, ventral; C, telson, dorsal; D, carapace, dorsal; E, carapace and pterygostomian flap, lateral; F, frontal region of carapace and cephalic appendages, dorsal; G, rostrum and cephalic appendages, lateral.

FIGURE 2. Munidopsis shulerae sp. nov., paratype, female (CL 10.0 mm), NE Gulf of Mexico, off Florida, USNM 1227847. A, carapace and pleon, right lateral view; B, sternite 3, dorsal; C, rostrum, and left antennular and antennal peduncles, ventral; D, right maxilliped 3, outer view; E, left cheliped, dorsal; F – H, right P 2 (upper), P 3 (middle), and P 4 (lower). Scales equal 2 mm (A, E – H), and 1 mm (B – D).

FIGURE 3. Munidopsis polita (Smith, 1883), male (CL 8.2 mm), NW Atlantic, eastern coast of United States, off Martha’s Vineyard, USNM 40039. A, entire animal (except missing right antennal flagellum, and right P 2, P 3); B, carapace and cephalic appendages, dorsal; C, frontal region of carapace and cephalic appendages, dorsal; D, carapace and cephalic appendages, lateral; E, sternum, ventral; F, telson, dorsal.