Eisothistos andamanensi

Kensley, B. & Schotte, M., 2000, New species and records of anthuridean isopod crustaceans from the Indian Ocean, Journal of Natural History 34, pp. 2057-2121 : 2092-2095

Quantanthur a andamanensi s sp. nov.

( Figures 25, 26)

Type material. HOLOTYPE: ZMUC, non-ovigerous m 9.1 mm, sta CRU-2039, Patang, Phuket Is., Thailand, coll. Dexter, 26 July 1994 . PARATYPES: ZMUC, one non-ovigerous m 9.0 mm, sta CRU-2039, Patang, Phuket Is., Thailand, coll. Dexter, 26 July 1994 . ZMUC, four non-ovigerous m 7.0± 7.9 mm, sta CRU-2044, Nai Hain, Phuket Is., Thailand, coll. Dexter, 5 October 1994 . USNM 253283 , four nonovigerous m 7.0± 8.5 mm, sta CRU-2045, Koto, Phuket Is., Thailand, coll. Dexter, 3 December 1994 .

Other material examined. ZMUC, three juveniles, sta CRU-2040, Nopoiotoush , Phuket Is., Thailand, coll. Dexter, 19 March 1995 . ZMUC, three juveniles, sta CRU-2041, Patang , Phuket Is., Thailand, coll. Dexter, 3 March 1995 . ZMUC, one non-ovigerous m, sta CRU-2042, Koto , Phuket Is., Thailand, coll. Dexter, 4 March 1995 . ZMUC, ®ve juveniles, sta CRU-2043, Nai Yang ¯at, Phuket Is., Thailand, coll. Dexter, 8 August 1994 . ZMUC, four non-ovigerous m, nine juveniles, sta CRU-2046, Patang , Phuket Is., Thailand, coll. Dexter, 6 December 1994 .

Diagnosis. Female: body about 14 times longer than greatest width. Pleonite 6 dorsally distinct from telson. Latter about 2.7 times longer than basal width, with slight`shoulder’ in posterior half, apically narrowly rounded, apex bearing two clumps of six setae each. Antennular peduncle article 2 bearing ®ve elongate ventrally-directed setae, article 3 with three setae, ¯agellum of three articles, tiny terminal article with three aesthetascs. Antennal peduncle article 2 with single distal elongate seta, article 4 with four elongate setae, article 5 with single seta, ¯agellum of two (perhaps three) articles. Mandibular palp articles each bearing single distal seta; lamina dentata having ®ve marginal serrations. Maxillipedal endite narrow, with two terminal setae, reaching to middle of palp article 3; terminal palp article attached obliquely at distolateral corner of article 3, bearing ®ve setae. Pereopod 1, carpus triangular, distally rounded, bearing scattered setae on posterior surface; propodus expanded proximally, palm convex, with scattered setae on mesial surface; unguis subequal to rest of dactylus, with tiny accessory seta at base. Pereopods 2 and 3, posterior surfaces of ischium, merus, carpus and propodus bearing relatively elongate setae; merus and carpus each having rounded distal projecting portion; propodus not ināted as in pereopod 1, with numerous ®ne setules on anterior surface; unguis about one-®fth length of dactylus, with fringed setae on posterior margin. Pereopods 4±7 becoming more elongate posteriorly, having elongate setae on posterior margins of merus, carpus and propodus; carpus having short free anterior margin, with short squat seta posterodistally. Pereopod 7, propodus with fringed scales on posterior margin, three bifringed setae posterodistally. Pleopod 1, endopod slightly shorter than exopod, with about ten distal plumose marginal setae. Uropodal exopod about 2.5 times longer than greatest width, lateral margin distally sinuous, apex subacute; endopod triangular, apically rounded, 1.8 times longer than basal width.

Remarks. Quantanthura andamanensi s is the second species of the genus from the Indian Ocean ( Q. remipes ( Barnard, 1914) , was recorded from the Agulhas area of South Africa) and bears some resemblance to Q. erica Poore and Lew Ton, 1986a , from the Bass Strait oOE southern Australia. The Australian species, however, lacks shoulders on the telson, has a less elongate uropodal exopod, a much broader maxillipedal endite, while the propodal palm of pereopod 1 is slightly concave.

Poore and Lew Ton (1986a) divided the species of Quantanthura into two groups, based on features of the antennules, mandible, maxilliped and posterior pereopods. Q. andamanensis , while not agreeing in all features, does have densely setose pereopods 4±7, has articles 1 and 2 of the mandibular palp subequal and does have long setae on articles 2 and 3 of the antennular peduncle, all features of group 2.

Etymology. The speci®c name is taken from the Andaman Sea, in which Phuket Island lies.