Pendanthura seminigra, Kensley & Schotte, 2000

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 : 2088-2090

Pendanthura seminigra sp. nov.

( Figure 22)

Type material. HOLOTYPE: USNM 253118 , ovigerous m 1.6 mm, sta K-AL-108, coarse sand between coral heads, Ile Picard, Aldabra, 3±5 m, 22 March 1086 . PARATYPES: USNM 253119 , three ovigerous m 1.5±1.8 mm, same data as holotype . USNM 253120 , one ovigerous m 1.3 mm, sta K-AL-109, reef ¯at, Picard Is., Aldabra, intertidal, 23 March 1986 .

Diagnosis. Ovigerous female: Integument not indurate. Body 5.5 times longer than greatest width at pereonite 1. Cephalon broader than middorsal length, with rounded rostrum reaching as far anteriorly as anterolateral corners. Eyes well pigmented. Strong anterodorsal articular hollows between pereonites 1 and 2, and 2 and 3. Pleonites 1±5 fused, together equal in length to pereonite 7; pleonite 6 fused with telson, forming raised`collar’ at base of telson; latter with sinuous lateral margins tapering to broadly rounded apex, bearing two large statocysts at about midlength; posterior half of telson with hyaline margin. Antennular peduncle of three articles, basal article equal to two distal articles together; ¯agellum of single short article bearing several setae and two aesthetascs. Antennal peduncle of ®ve articles, article 2 longest and broadest; ¯agellum of single short article bearing numerous setae. Mandibular palp article about 2.5 times longer than wide, with two distal setae; incisor of three cusps; lamina dentata with four marginal serrations; molar short, bluntly triangular. Maxilla as ®gured. Maxilliped with low rounded endite; palp of single broad article bearing seven setae distally. Pereopod 1, carpus distally hyaline, acute; propodus ināted, palmar area hyaline, almost straight; unguis equal in length to rest of dactylus, with slender elongate accessory seta. Pereopod 2 less robust than pereopod 1, propodus with strong serrate sensory spine posterodistally. Pereopod 7, carpus with anterior free margin about half length of posterior margin; propodus with several fringed scales on posterior margin plus strong serrate sensory seta posterodistally; dactylar unguis with short accessory seta. Pleopod 1, both rami forming operculum but endopod larger than exopod; exopod about two-thirds in length, and slightly narrower than endopod, with nine marginal plumose setae; endopod with four relatively short distal setae. Uropodal exopod elongate-ovate, outer margin crenulate with fringed setae, reaching to base of endopod; latter distally rounded, with several marginal setae.

Male: Unknown.

Colour. Anterior half of animal more heavily pigmented than posterior. Cephalon and pereonite 1 and propodus of pereopod 1 dark blackish-brown; pereonite 2 anteriorly pigmented; pereonites 3±7, pleon, pleotelson and uropods with paler reticulation of pigment.

Remarks. The present species diOEers from the three previously described species (see Kensley 1984: 18) in several respects: the pigment pattern is distinctive; the uniarticulate mandibular palp is longer than in any of the earlier species, the maxillipedal endite is more reduced; the endopod of pleopod 1 is relative broader than in any of the earlier species.

Etymology. The species name, from the Latin meaning`half-black’, refers to the black pigmentation of the anterior half of the animal.