NEOCLIMENES HOLTHUISI N. GEN., N. SP., A NEW DEEP-SEA PONTONIINE SHRIMP FROM THE SOUTH CHINA SEA (, )

BY

MASAKO MITSUHASHI1,4), XINZHENG LI2,5) and TIN-YAM CHAN3,6) 1) Laboratory of Biology, Osaka Institute of Technology, Ohmiya, Asahi-ku, Osaka 535-8585, Japan 2) Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China 3) Institute of Marine Biology, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 202, Taiwan, R.O.C.

ABSTRACT

Neoclimenes holthuisi n. gen., n. sp., a new pontoniine shrimp and species is described from Pratas (Dongsha) in the South China Sea from about 500 m depth. The new genus has the hepatic spine bearing a distinct basal suture, similar to the recently described genus, Patonia Mitsuhashi & Chan, 2006, also from deep water around Taiwan, but both genera differ in the shape of the rostrum and the structure of the chelipeds.

RÉSUMÉ

Neoclimenes holthuisi n. gen., n. sp., une crevette Pontoniinae appartenant à un genre et une espèce nouvelle est décrite à partir d’un matériel obtenu à Pratas (Dongsha) dans la mer de Chine du Sud à une profondeur de l’ordre de 500 m. Dans le nouveau genre, l’épine hépatique présente une suture basale distincte, similaire à celle observée dans le genre récemment décrit, Patonia Mitsuhashi & Chan, 2006, lequel provient aussi des eaux profondes au large de Taïwan. Cependant, les deux genres diffèrent par la forme du rostre et la structure des chélipèdes.

INTRODUCTION

Recent deep-sea biodiversity surveys in Taiwan and adjacent areas (the TAI- WAN cruises) have collected many new decapod . Previously, two

4) e-mail: [email protected] 5) e-mail: [email protected] 6) e-mail: [email protected]

© Koninklijke Brill NV, Leiden, 2010 Studies on : 515-527 516 CRM 014 – Fransen et al. (eds.), LIPKE BIJDELEY HOLTHUIS MEMORIAL VOLUME new deep-sea pontoniine shrimps were described based on the TAIWAN mate- rial, namely Patonia mclaughlinae Mitsuhashi & Chan, 2006 and Periclimenes sandybrucei Mitsuhashi & Chan, 2009. In the present paper, another new pon- toniine species is described based on an ovigerous female collected off Pratas (Dongsha, southwest of Taiwan and under its jurisdiction) in the South China Sea during the recent TAIWAN deep-sea surveys. The new species has the he- patic spine bearing a distinct basal suture. This unusual feature is so far only known in the pontoniine genera, Dasella Lebour, 1945, Paranchistus Holthuis, 1952, Allopontonia Bruce, 1972, Zenopontonia Bruce, 1975 and Patonia Mit- suhashi & Chan, 2006. Among these genera, the new species is most similar to Patonia in having the dorsal rostrum entirely dentate, the body laterally compressed, and the third to fifth pereiopods slender and with biunguiculate dactyli. However, the new species does not fit the generic definition of Patonia in having the ventral margin of the rostrum armed with distinct teeth, the basal antennular segment bearing only a single anterolateral spine, and the second pereiopods much larger than the first pereiopods. Thus, a new genus is estab- lished to accommodate the present species. Carapace length (cl) and body length (bl) are measured dorsally from the postorbital margin to the posterior border of the carapace and to the telson, respectively. The specimen is deposited in the National Taiwan Ocean University, Keelung (NTOU).

SYSTEMATIC ACCOUNT

Family PALAEMONIDAE Rafinesque, 1815

Subfamily PONTONIINAE Kingsley, 1878 Genus Neoclimenes n. gen. Type species. — Neoclimenes holthuisi n. sp. by present designation. Etymology. — Named from the closely related genus Periclimenes and “neo-” from neos (Greek, new). Gender masculine. Diagnosis. — Body subcylindrical. Rostrum well developed, slender, ex- ceeding eye, lateral carina feebly developed; dorsal margin dentate, posterior- most (epigastric) tooth with basal suture; ventral margin dentate. Carapace smooth; inferior orbital angle distinct; antennal spine submarginal; supraor- bital spine absent; hepatic spine present, with basal suture. Abdomen smooth, third somite not posteriorly produced, pleura broadly rounded. Telson with two