Upogebia ruiyui, Liu, 2015

Liu, Wenliang, 2015, Two new species of the genus Upogebia Leach, 1814 (Crustacea: Decapoda: Gebiidea: Upogebiidae) from the South China Sea, Raffles Bulletin of Zoology 63, pp. 418-425 : 421-424

Upogebia ruiyui , new species

( Figs. 4–6 )

Material examined. Holotype: female (cl. 4.2 mm), MBM 136790/ CJ 97C-160, Sanya Bay, Hainan Province, South China Sea, intertidal zone with sandy substratum, coll. Xinzheng Li, 3 March 1997 . Paratype: female (cl. 3.0 mm), MBM 136790/C597C-160, same data as holotype.

Description. Rostrum ( Figs. 4 , 5A, B ) triangular, about 1.1 times as long as basal width; anterior margin truncate, projecting beyond eyes, bearing 2 strong triangular teeth on each lateral margin, one pair of that on lateral angle, and the other pair of that on the middle of lateral margin, without infrarostral spine; dorsal surface with dense setae and scattered many small tubercles extending onto gastric region of carapace. Carapace ( Fig. 5A, B ) with narrow lateral ridges, 5–6 small triangular teeth on lateral margin, weakly projecting forward, divided from lateral margin of rostrum by shallow notch; dorsal surface of carapace with dense setae but without conspicuous tubercles; anterolateral border unarmed; cervical groove long and deep, unarmed; postorbital region unarmed.

Eyestalks stout ( Fig. 5B ), unarmed; cornea darkly pigmented. Antennular peduncle reaching article 4 of antennal peduncle, unarmed. Antennal peduncle unarmed; article 3 with ovate scale on upper surface.

Maxilliped 3 ( Fig. 5C ) moderately stout; exopod consisting of 2 articles, reaching to proximal third of merus.

Female pereopod 1 chelate, strong, symmetrical ( Fig. 6A , B). Basis unarmed. Ischium with 3 ventral spines. Merus about 2.3 times as long as high, with row of about 10–11 ventral spines and 2 subterminal spines on dorsal margin. Carpus triangular, about 0.5 length of merus, with 1 small lower subdistal spine, mesial face with 4 spines near to distal end. Propodus 1.6 times as long as high, 2.4 length of carpus, upper margin with row of 6–7 tubercles on basal half and 1 subterminal tubercle, lower margin with row of 10–11 tubercles; mesial face unarmed. Fixed finger slender, narrow and sharply pointed; cutting edge slightly curved, with 2 inconspicuous teeth. Dactylus strong, terminating in corneous tip, about 0.4 length of palm; extensor margin arched, with 2 proximal small teeth; cutting edge curved, unarmed; lateral surface carinate medially.

Pereopod 2 ( Fig. 6C ) unarmed; merus about 3.6 times as long as high; carpus about 0.5 length of merus; propodus about 2.2 times as long as high; dactylus slender, 0.7 length of propodus.

Pereopod 3 ( Fig. 6D ) unarmed; merus about 4.4 times as long as high; carpus about 0.5 length of merus; propodus about 2.6 times as long as high; dactylus slender, 0.9 length of propodus, tapering distally.

Pereopod 4 ( Fig. 6E ) unarmed; dactylus slender and elongate, 1.1 length of propodus, tapering distally.

Pereopod 5 ( Fig. 6F ) semichelate, unarmed; dactylus elongate and curved.

Abdominal tergites smooth. Telson ( Fig. 5D ) subrectangular, 0.6 times as long as wide, and about 0.7 length of abdominal somite 6; bearing two transverse crista dentata consisting of a row of small spines on dorsal surface; posterior margin truncated, unarmed.

Female pleopod 1 present, uniramous, consisting of 2 articles. Uropodal protopod ( Fig. 5D ) bearing one spine each near bases of endopod and exopod; exopod rounded, almost as long as wide, bearing some small spines on distolateral margin, slightly convex on mesial margin; endopod shorter than exopod, about 1.1 times as long as wide.

Remarks. This new species closely resembles Upogebia allspachi Sakai, 2006 known from Fiji, in the form of rostrum, about 1.1 times as long as basal width and both are armed with 2 strong triangular teeth on each lateral margin ( Sakai, 2006). It differs from U. allspachi in the upper margin of the propodus of pereopod 1 being armed with a row of 6–7 small tubercles (versus with a row of six sharp spines); lower margin being armed with a row of 10–11 small tubercles (versus only with a median triangular tooth), and the dorsal surface of the telson bearing two transverse denticulate carinae (versus bearing one strong transverse carina).

Etymology. The species is named in honour of the late Professor Ruiyu Liu (J. Y. Liu), the Institute of Oceanology, Chinese Academy of Sciences, for his great contribution to the Chinese carcinology.

Distribution and habitat. Presently known only from the type locality.

Figures

Fig. 4. Upogebia ruiyui, new species. Holotype female, C597C-160/MBM136790, entire animal, laterral view. Scale bar = 1mm.

Fig. 5. Upogebia ruiyui, new species. Holotype female, C597C-160/MBM136790. A, anterior carapace, lateral view; B, anterior carapace, dorsal view; C, right maxilliped 3, outer view; D, abdominal somite 6, telson and uropods, dorsal view. Scale bars = 1 mm (A, B); 1.25 mm (C); 1.6 mm (D).

Fig. 6. Upogebia ruiyui, new species. Holotype female, C597C-160/MBM136790. A, right pereopod 1, outer view; B, right pereopod 1, inner view; C, pereopod 2, outer view; D, peorepod 3, outer view; E, peorepod 4, outer view; F, peorepod 5, outer view. Scale bar = 1mm.