Plesionika spinensis Chace, 1985

Li, Xinzheng & Komai, Tomoyuki, 2003, Pandaloid Shrimps From The Northern South China Sea, With Description Of A New Species Of Plesionika (Crustacea: Decapoda: Caridea), Raffles Bulletin of Zoology 51 (2), pp. 257-275 : 269

Plesionika spinensis Chace, 1985

Plesionika spinensis Chace, 1985:129 , figs. 58, 59 [type locality: western Mindanao Sea off Murcielagos Bay, Philippines]

Material examined. – 1 female (cl 9.4 mm) ( IOCAS), CN K7 B-11, 19 00’N, 112 30’E, 472 m, sand, AT, coll. Z. Tang, 17 Feb.1959 ; 1 female (cl 7.5 mm) ( IOCAS), CN K122 B-49, 19 00’N, 112 30’E, 300 m, sand, AT, coll. S. Shen, 8 Feb.1960 .

Supplemental material. – 1 male (cl 10.1 mm), 1 ovig. female (cl 10.1 mm) (paratypes; CBM-ZC, transferred from USNM 205305 ), Albatross : stn 5517, west of Mindanao Sea, Philippines, 08 45.30’N, 123 33.45’E, 309 m, 9 Aug.1909 .

Distribution. – Previously known only from the Philippines at depths of 199- 333 m. The present specimens extend the geographical range of this species to north and west and bathymetrical range down to 472 m.

Remarks. – The present specimens fit well the original description of P. spinensis by Chace (1985). The identification was confirmed by comparison with two paratypes (USNM 205305).

This species is similar to the members of the Plesionika ensis (A. Milne Edwards, 1881) species group, including P. ensis from the western Atlantic and P. reflexa Chace, 1985 , from the western Pacific. The three species share the following features: the upper orbital lobe is distinct; the third abdominal somite is armed with a median spine on the posterodorsal margin; the posterior three pereopods are not greatly elongate or extremely thin, with carpi being subequal to or slightly shorter than the propodi. Plesionika spinensis can be readily distinguished from the two relatives by the rostrum with dorsal margin dentate over the entire length, the absence of the ventral membranous part of the branchiostegite of the carapace, the possession of a median tooth on the posterodorsal margin of the fourth abdominal somite, and the elongate dactyli of the third to fifth pereopods.