Mursia murimuria, Galil, Bella S., 2013

Galil, Bella S., 2013, On a collection of calappid crabs (Crustacea: Decapoda: Brachyura) from Fiji, with a description of a new species of Mursia, Zootaxa 3734 (4), pp. 485-491 : 487-489

Genus Mursia Desmarest, 1823

Mursia murimuria n.sp. ( Figs 1 , 2 ).

Material examined. Holotype. BORDAU 1, stn CP1467, 18°12’S 178°36’W, 417–427 m, 6.03.1999, 1♂ (24.2 mm) MNHN-IU-2013-6996. Paratypes: BORDAU 1, stn DW1421, 17°08’S 178°59’W, 403–406 m, 28.02.1999, 1 ♂ (25.1 mm), 1 ♀ (17.1 mm), MNHN-IU-2013-6997. — MUSORSTOM 10, south of Viti Levu, stn CP1386, 18°18.5’S 178°05.1’E, 230–344 m, 19.08.1998, 1 ♂ (14.5 mm), 1 ♀ (13.6 mm), MNHN-IU-2013-6989.

Description. Carapace transversely subovate, convex, nearly 1.2 wide as long. Dorsal surface densely covered with flattened granules of similar size. Rounded protuberances, covered with coalescent granules, disposed in 7 irregular radial rows on dorsal surface. Gastric, cardiac, intestinal regions separated from branchial regions by shallow, sinuous longitudinal grooves. Anterolateral margin arcuate, beaded, denticulate, denticles successively smaller posteriorly. Lateral spine acuminate, prominently upcurved, may reach more than 0.3 carapace width, proximally granular ( Fig. 1 ). Posterolateral margin oblique, sharply convergent, minutely beaded, angled medially. Posterior margin beaded, lateral teeth triangular, dorsoventrally flattened, median lobe effaced. Frontal margin projecting slightly beyond orbits, trilobate, median lobe broadly triangular, at lower plane than lateral lobes; lateral lobes rounded, separated from supraorbital margin by shallow concavity. Antennule obliquely folded. Supraorbital margin with single fissure, minutely granular, with long plumose setae. Inner orbital tooth ogival, separated from outer orbital margin by deep V-shaped cleft, from front by orbital hiatus. Antennae short, slender, basal segment subrectangular, lodged in orbital hiatus. Eye retractable, eyestalk short, granular, setose. Buccal frame rhomboidal, narrowing anteriorly. Thick fringe of plumose setae running the length of third maxilliped exopod, merus; ischium granular, setose. Subhepatic region densely setose. Thoracic sternum narrow, granular. Male abdomen with segments 3–5 fused; prominent trilobate carina on second segment, rounded lateral lobes slightly more prominent than trapezoidal median lobe; penultimate segment subquadrate, lateral margins slightly sinuous; telson triangular, subequal with penultimate segment. Chelipeds massive, subequal. Merus distally bispinose, distal spine longer, stouter than lateral spine. External surface of manus convex, closely granular, upper margin crested, setose, bearing 8 denticles; first tooth low, teeth 2–4 triangular; successive teeth progressively lower, wider. External surface with 9 granular tubercles in 3 oblique rows, 2 tubercles near base of crest; proximal tubercle in lowest row ram-shaped, slightly upcurved, median tubercle dorsoventrally flattened, rounded; distal tubercle smallest, rounded. Internal surface with band of setae near lower margin. Lower margin minutely serrate. Upper margin of dactylus crested, setose, proximally granular; inner surface bearing stridulating ridge of nearly 30 striae. Left dactylus with curved rounded tooth proximally, fitting into depression in pollex. Pereiopods 2–5 slender, laterally compressed, meri minutely granular; dactylus slender, longer than propodus, styliform. First male pleopod thick, slightly curved, distally auriculate, single line of spinules on interior margin. Second male pleopod with corneous distal portion, crook-shaped, tip upcurved ( Fig. 2 ).

Color (preserved specimens). Internal surface of palm cream with small bright orange patch distally near the articulation with the dactylus.

Etymology. Murimuria is part of the underworld in Fijian mythology, as in the depths in which this species occurs. The name is used as a noun in apposition.

Remarks. Several Mursia species are notable for their exceedingly long (> 0.3 carapace width) lateral carapace spines: M. armata de Haan, 1837, M. longispina Crosnier, 1997 , M. baconaua Galil & Takeda, 2004 , and M. aurorae Galil & Ng, 2009. Mursia murimura n. sp. is distinguished from these species in possessing a thick, distally auriculate first male pleopod, rather than a slender and evenly tapering first male pleopod. It is further distinguished from M. armata in its slender lateral carapace spines, longer cheliped merus spines, lack of cylindrical protuberances on the posterior margin of the carapace, and crook-shaped rather than looped distal portion of the second male pleopod; it differs from M. longispina in possessing shorter lateral carapace spines (0.3 rather than 0.5 carapace width), a longer spine distally on the cheliped merus and the absence of cylindrical protuberances on the posterior margin of the carapace; it differs from M. baconaua in possessing a longer distal spine on the cheliped merus and in the shape of the second male pleopod (distal portion hook-shaped, tip twisted in M. baconaua ); it differs from M. aurorae in its slender lateral carapace spines, longer spine distally on the cheliped merus and the absence of cylindrical protuberances on the posterior margin of the carapace. The first and second male pleopods of M. murimura n. sp. ( Fig. 2 ) are similar to those of M. diwata Galil & Takeda, 2004 (Fig. 5 E, D) collected off Balicasag Island, Philippines. The new species, however, is distinguished by the much longer lateral carapace spine (0.3 in contrast to less than 0.2 carapace width), and even longer spine distally on the cheliped merus, than in the M. diwata specimens (n=45, CL 8.4–21.9 mm) collected off Balicasag (Galil & Takeda, 2004; Fig. 9).

Mursia musorstomia Galil, 1993

Mursia musorstomia Galil, 1993: 366 , fig. 4 f, 8 g-h, 10 a-b, 13. — Ng & Richer de Forges 2007: 320.

Material examined. BORDAU 1. stn CP1411, 16°05’S 179°28’W, 390–403 m, 26.02.1999, 1 ♂ (23.1 mm) MNHN-IU-2013-6968; stn CP1444, 17°11’S 178°41’W, 398–409 m, 3.03.1999, 1 ♀ (17.8 mm), 1 pre-adult, MNHN-IU-2013-6965; stn CP1476, 19°41’S 178°11’W, 310–420 m, 8.03.1999, 2 pre-adults (9.9, 10.1 mm), MNHN-IU-2013-6992; stn CP1479, 20°58’S 178°45’W, 450–460 m, 9.03.1999, 1 ♀ (16.0 mm), 8 pre-adults, MNHN-IU-2013-6964; stn CP1481, 20°57’S 178°45’W, 441–506 m, 9.03.1999, 2 ♂ (11.2, 17.5 mm), 4 ♀ (12.2– 15.9 mm), 13 pre-adults, MNHN-IU-2013-6961; stn 1481, 20° 57.50S 178° 44.90W, 441–506 m, 9.03.1999, 1 preadult (7.4 mm), MNHN-IU-2013-6993; stn CP1493, 18°43’S 178°24’W, 429–440 m, 11.03.1999, 1 ♀ (18.2 mm), MNHN-IU-2013-6963; stn CP1495, 18°53’S 178°30’W, 420–445 m, 12.03.1999, 1 ♀ (20.0 mm), N° IU-2013- 6962; stn CP1504, 18°13’S 178°34’W, 427–440 m, 13.03.1999, 1 pre-adult (10.5 mm), MNHN-IU-2013-6994.

Distribution. Known from New Caledonia, Chesterfield Is, Loyalty Is (Galil1993). New record for Fiji.

Figures

FIGURE 1. Mursia murimuria n. sp. Fiji, BORDAU 1, stn DW 1421, male (cl 25.1 mm), Paratype, MNHN-IU- 2013, dorsal view of carapace. Photo by Pierre Lozouet (MNHN).

FIGURE 2. Mursia murimuria n. sp. Fiji, BORDAU 1, stn DW 1421, male (cl 25.1 mm), paratype, MNHN-IU- 2013. a. first male pleopod, scale 2 mm; b. tip of first male pleopod, scale bar: 1 mm; c. second male pleopod, scale bar: 2 mm; d. tip of second male pleopod, scale bar: 1 mm. Drawing by Jean-François Dejouannet (MNHN).