Parapleisticantha ludivinae Forges, Ng & Ahyong, 2013, n. sp.
Creators: name: Forges, Bertrand Richer De
name: Ng, Peter K. L.
name: Ahyong, Shane T.
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Inachidae
Parapleisticantha
Parapleisticantha ludivinae

description: Parapleisticantha ludivinae n. sp.
(Figs. 4, 5, 6 F–H)
Material examined. Holotype: Philippines, Bohol, Panglao, Balicasag Is., coll. tangle nets, P.K.L. Ng, July 2003 (NMCR): male (22.9 × 19.2 mm).
Paratypes: Same data as holotype, (ZRC 2012.1200): 2 ovigerous females, 19.5 × 17.4 mm, 17.9 × 14.5 mm; Balicasag Is., coll. tangle nets, P.K.L. Ng, March 2004 (AM P90247): 3 males (18.5 × 15.1 mm to 22.3 × 18.3 mm), 1 female (21.0 × 17.4 mm); Balicasag Is., 200–300 m, coll. tangle nets, P.K.L. Ng, June 2002 (ZRC 2013.0316): 3 males (16.8 × 13.4 mm to 25.7 × 20.2 mm), 3 ovigerous females (17.1 × 14.1 mm to 19.7 × 16.8 mm); Balicasag Is., from fishermen with tangle nets, coll. P.K.L. Ng, July 2003 (ZRC 2012.1218): 1 male (21.7 x 17.8 mm); Balicasag Is., coll. fishermen with tangle nets, April 2004 (ZRC 2012.1175): 1 male (25.7 × 21.5 mm); Balicasag Is., 200–300 m, coll. tangle nets, P.K.L. Ng, May 2004 (ZRC 2013.0320): 2 males (16.2 × 13.3 mm, 18.0 × 14.7 mm), 3 ovigerous females (17.4 × 14.3 mm to 20.9 × 16.7 mm); station PN 1, Balicasag Is., from fishermen with tangle nets, November 2003 (ZRC 2013.0317): 1 female (18.2 × 14.7 mm); station P 4, Balicasag Is., from fishermen with tangle nets, coll. PANGLAO 2004, 8 June 2004 (ZRC 2013.0318): 1 male (21.1 × 17.4 mm); station PN 1, Balicasag Is., from fishermen with tangle nets, coll. PANGLAO 2004, 29 May 2004 (MNHN): 1 male (21.4 × 17.7 mm), 1 ovigerous female (15.9 × 12.8 mm); Noto Is., coll. local fishermen, tangle nets, May 2004 (ZRC 2013.0319): 1 ovigerous female (16.0 × 12.8 mm). All material from Panglao, Bohol, Philippines.
Description. Small-sized species (smallest ovigerous female less than 16 mm carapace length); carapace with branchial, cardiac and gastric regions well delimited, covered regularly with short spiniform granules, spinules; larger spines arranged as follows: 2 on gastric area, none on cardiac area, 1 on branchial area; branchial regions strongly convex, distinctly swollen (Fig. 4 A, B). Rostrum with 2 prominent short horns, about 1/4 to 1/5 of carapace length, widely diverging, forming V-shape (Figs. 4, 5 A), each horn with 0–2 dorsal spines, 2 or 3 lateral spines and 1–3 ventral spines; distal border of the antennular fossa with strong spine; sharp postocular spine; subhepatic tooth very long (Figs. 4, 5 A). Eyes with short peduncle, small rounded cornea (Figs. 4, 5 A). Supraorbital eave large, border with 3 teeth; supraocular spine longest; intercalated spine and infraocular spine sharp of same size (Fig. 4). Hepatic region with several spines, strongest pointing obliquely forwards (Figs. 4, 5 A, C). Interantennular spine (true rostrum) bifid (Fig. 5 A). Basal antennal article long, with 4 long spines arranged on border of article, 1 internal, 3 external; strong spine pointing outward at level of green gland opening (Figs. 4 C, 5A). Third maxilliped pediform, ischium with 2 longitudinal rows of sharp granules on outer surface, outer row with 4 or 5 granules, inner row with 7 or 8 granules; merus subtriangular, as long as broad, with 2 sharp granules on outer surface. Male chelipeds with strong chelae, inflated palm; dactylus with 2 low, broad teeth on inner border; cross-section of merus trigonal, each angle with row of sharp spines; outer palm surface covered with small, blunt or acute tubercles; propodal margin below articulation of dactylus and pollex gently serrulated, without projection; cutting edge of propodal finger with unevenly sized low teeth (Figs. 4 A, 5D). Ambulatory legs long; P2 longest, merus 0.95–1.11 cl (males), 0.80–0.88 cl (females); P5 shortest, merus 0.63–0.73 cl (males), 0.53–0.63 cl (females); merus with subdistal dorsal spine, dorsal and ventral margins lined with sharp spinules (Fig. 4 A). Abdomen of both sexes with 6 free somites and telson; distal margin of somite 6 gently concave (Fig. 5 B). G1 very stout, straight along basal two-thirds, distal part sharply bent outwards, forming 90° angle, lined with setae on straight part, distal part without subdistal process (Fig. 6 F–H); G2 about half as long as G1, tip spatuliform.
Etymology. The species is named after a colleague, Ms Ludivina Labe of the Bureau of Fisheries and Research, Philippines, one of the cruise leaders of AURORA 2007, and who has helped us on numerous occasions with our studies on Philippine crabs.
Remarks. Parapleisticantha ludivinae n. sp. is superficially similar to P. japonica Yokoya, 1933. Compared to P. japonica, however, P. ludivinae n. sp. has the branchial regions of the carapace distinctly more inflated and rounded (compare Figs. 1 A, B, 3A, B, 2D with Figs. 4 A, B, 5D); the rostral horns are relatively shorter (compare Figs. 1 A, B, 3A, B, 2D with Figs. 4 A, B, 5D); the ambulatory legs are proportionately more slender and longer, especially the P2 merus (compare Figs. 1 A, 3A and Fig. 4 A). The chelae are also different being relatively longer and more slender in P. ludivinae n. sp. (Fig. 5 E) (versus relatively stouter and shorter in P. japonica, Fig. 2 E); the cutting edge of the dactylus is lined with low, broad and not well differentiated teeth (Fig. 5 E) (versus with evenly sized distinct teeth in P. japonica, Fig. 2 E); and the junction of the dactylar and propodal fingers is gently serrulated but not prominently protruding or forming a process (Fig. 5 E) (versus with a distinctly granulated subtruncate process present in P. japonica, Fig. 2 E). Furthermore, the distal margin of abdominal somite 6 of P. ludivinae n. sp. is gently concave (Fig. 5 B) (versus deeply concave in P. japonica, Fig. 2 B); and most significantly, the G1 is proportionately stouter (Fig. 6 F–H) (versus relatively more slender in P. japonica, Fig. 6A–C).
Acknowledgements
The 2000–2004 specimens from the Philippines were collected by the second author as part of a joint program of Raffles Museum of Biodiversity Research, National University of Singapore (NUS); the University of San Carlos (USC), Cebu; and Holy Name University (HNU), Bohol. Special thanks are due to Lawrence Liao (USC) and Father Florante Camacho (HNU), who facilitated the research work. The PANGLAO 2004 expedition, which collected some of the material, was organised by MNHN (under Philippe Bouchet) with support from NUS and the National Ocean University, Keelung, Taiwan (under Chan Tin Yam), as well as the ASEAN Research Centre for Biodiversity and Conservation (Manila). Support from the Bureau of Fisheries and Aquatic Resources (BFAR), Manila, is acknowledged. Specimens from KMNH were loaned through the courtesy of Michitaka Shimomura; and we also thank Hironori Komatsu (National Science Museum, Tokyo) for help and for facilitating this loan.
description: Published as part of Forges, Bertrand Richer De, Ng, Peter K. L. & Ahyong, Shane T., 2013, Parapleisticantha Yokoya, 1933, a valid genus of deep-sea inachid spider crab from Japan and the Philippines (Crustacea: Decapoda: Brachyura: Majoidea), with the description of a new species, pp. 15-26 in Zootaxa 3635 (1) on pages 21-25, DOI: 10.11646/zootaxa.3635.1.2, http://zenodo.org/record/283510