Exopalaemon orientis ( Holthuis, 1950 )

Li, Xinzheng, Bruce, Alexander J. & Manning *, Raymond B., 2004, Some Palaemonid Shrimps (Crustacea: Decapoda) From Northern South China Sea, With Descripitions Of Two New Species, Raffles Bulletin of Zoology 52 (2), pp. 513-553 : 515-516

Exopalaemon orientis ( Holthuis, 1950)

( Fig. 2 )

Leander longirostris japonicus - Ortmann, 1890: 519, pl. 37: fig. 14. [not Palaemon japonicus De Haan, 1849 = Macrobrachium japonicum (De Haan, 1849) ]

Palaemon (Exopalaemon) orientis Holthuis, 1950: 49 ; Liu, 1959: 36.

Exopalaemon orientis - Holthuis, 1980: 83; Liu et al., 1990b: 246, Fig. 38; Hayashi, 1999a: 392, Figs. 380g-m, 381.

Material examined. – 110 juv. ( IOCAS) , 3 juv. (SI), 2 juv. ( ZRC), Haikou, Hainan Is. , coll. J. Y. Liu, 18 Jan.1956 ; 28 juv., CN 56 - K067B2, Haikou, Hainan Is. , coll. J. Y. Liu, 28 Jan.1956 .

Diagnosis. – Rostrum armed with 5-7 teeth on basal crest, 1 dorsal subterminal tooth, and 6-7 ventral teeth; carapace with antennal and branchiostegal spines, branchiostegal suture distinct. Third to sixth abdominal somites not sharply carinate in dorsal midline. Mandible with 3-segmented palp, incisor process with 4 teeth. First pereiopods slender, chela about 0.75 length of carpus. Second pereiopods with carpus 0.6 as long as chela. Third pereiopods with dactyl about 0.75 as long as propodus, ventral margin of propodus with 4 spines. Fifth pereiopods with dactyl no more than half as long as propodus, with some setae, instead of a ventral spines.

Distribution. – Japan to South China Sea.

Remarks. – The present species is very close to E. styliferus (H. Milne Edwards, 1840) . The latter can be distinguished from this species by having a rostrum with relatively more teeth, i.e., 1-3 dorsal subterminal teeth and 6-10 ventral teeth, and the 3rd pereiopod with the dactyl no more than half as long as propodus. E. orientis was previously recorded from Fujian, Taiwan and Guangdong in Chinese waters ( Liu et al., 1990b).

Figures

Fig. 2. Exopalaemon orientis Holthuis, 1950. a, carapace and rostrum, lateral view; b, mandible; c, 1st pereiopod; d, 2nd pereiopod; e, 3rd pereiopod; f, same, dactyl and propodus; g, 5th pereiopod; h, same, dactyl and propodus.