Arcitalitrus belbucca, R Peart, 2006

R Peart, 2006, The Amphipod Genus Arcitalitrus (Crustacea: Amphipoda: Talitridae) of New South Wales Forests, With Descriptions of Six New Species, Records of the Australian Museum 58, pp. 97-118 : 99

Arcitalitrus belbucca n.sp.

Figs. 1, 8–10

Type material. HOLOTYPE, ♀, 14.0 mm, AM P60959, 11 November 1999, M. Gray, G. Milledge and H. Smith . PARATYPES, 65 specimens AM P60967 . Paratypes are all from the type locality.

Type locality. Belbucca Road , 1.5 km from junction with Middle Ridge Road , Irishman State Forest (30°32'58"S 152°40'14"E), west of Sydney, New South Wales, Australia .

Description. Based on holotype female. Body shape normally laterally compressed; cuticle calcification absent. Eye medium (1 ⁄ 5 – 1 ⁄ 3 head length). Antenna 2 longer than head and first 3 pereonites; peduncular articles narrow. Mandible left lacinia mobilis 4 dentate, or 5 dentate. Maxilliped outer plate distally acute/arcuate; palp dactylus present and distinct. Pereonite 1 sternite without papillose process. Gnathopod 1 not sexually dimorphic; simple; merus and carpus not expanded; propodus subrectangular; palm absent; dactylus longer than palm. Gnathopod 2 not sexually dimorphic; chelate; basis narrow; merus and carpus expanded posteriorly; propodus “mitten-like”; palm obtuse; smooth; dactylus shorter than palm. Pereopods 3–7 long (½ length of body); simplidactylate. Pereopod 4 carpus similar in length to pereopod 3 carpus, dactylus similar to pereopod 3 dactylus. Pereopod 7 posterodistal lobe present. Gill 2 lobate, not incised. Gills 3–5 lobate, smaller than gills 2 and 6. Gill 6 lobate, anterior margin convoluted, subapically incised along posterior margin. Oostegites long (length greater than 2× width), weakly setose, setae with simple smooth tips. Epimera 1 to 3 not convergent. Epimeron 2 subequal in length to epimeron 3. Epimeron 3 posteroventral margin smooth, posteroventral corner with small subacute tooth. Pleopod 1 well developed, biramous, rami subequal in length to peduncle; inner ramus with 13 articles; outer ramus with 9 articles. Pleopod 2 well developed, biramous, rami subequal in length to peduncle; inner ramus with 8 articles; outer ramus with 7 articles. Pleopod 3 reduced, rami absent. Uropod 1 not sexually dimorphic; peduncle with 8 robust setae on peduncle; inner ramus shorter than outer ramus, with 3 robust setae on the margins, with 5 apical robust setae; outer ramus without marginal robust setae, with 3 apical robust setae. Uropod 2 not sexually dimorphic; peduncle with 3 robust setae; inner ramus subequal in length to outer ramus, with 2 marginal robust setae, 4 apical robust setae; outer ramus without marginal robust setae, with 4 apical robust setae. Uropod 3 peduncle with 1 robust setae; ramus shorter than peduncle, ramus linear (narrowing), with 2 robust setae. Telson longer than broad, deeply incised, with marginal and apical robust setae, with more than 10 robust setae on whole telson.

Etymology. Named after Belbucca Road, in Irishman State Forest, the type locality and treated as a noun in apposition.

Remarks. Arcitalitrus belbucca is a member of the “Sylvaticus” species group. It is the only Arcitalitrus with a deeply incised telson. Arcitalitrus belbucca and Ar. nana appear to be sister taxa. They share many characters and both have more than 10 dorsal robust setae on the telson.

Distribution. New South Wales: Irishman State Forest, west of Sydney.