Arcitalitrus nana R Peart 2006, n.sp.
Creators: name: R Peart
Publisher: name: Zenodo
Year: 2006
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Arcitalitridae
Arcitalitrus
Arcitalitrus nana

description: <i>Arcitalitrus nana</i> n.sp. Figs. 4, 18–20 <b>Type material</b>. HOLOTYPE, &amp;female;, 15.0 mm, AM P60956, December, 1999, M. Gray, G. Milledge and H. Smith. PARATYPES, male AM P60955; 35 specimens, AM P60964. Paratypes are all from the type locality. <b>Type locality</b>. Five km ENE of Lowanna, Nana Creek State Forest (30°11'51"S 152°56'53"E) New South Wales. <b>Other material examined</b>. New South Wales, Australia: Junction of Urumbilum Creek road and Loudens road, Orara State Forest (30°19'35"S 152°55'00"E), 5 specimens, 9–23 December 1999, collected from pitfall traps, M. Gray, G. Milledge and H. Smith; nearly 2 km east of Mount Kariong, Brisbane Water National Park (33°27'50"S 151°17'04"E), 40 specimens, 1–15 December 1999, collected from pitfall traps, M. Gray, G. Milledge and H. Smith; end of Little North Arm road, west bank of Rosewood River, Dorrigo National Park (30°24'06"S 152°46'18"E), 25 specimens, 10–24 November 1999, collected from pitfall traps, M. Gray, G. Milledge and H. Smith; Reids Creek road, Gladstone State Forest (30°31'01"S 152°48'29"E), 20 specimens, 12– 25 November 1999, collected from pitfall traps, M. Gray, G. Milledge and H. Smith; beside Hacking River, Lady Wakehurst Drive, Royal National Park (34°09'47"S 151°00'55"E), 35 specimens, 6–20 December 1999, collected from pitfall traps, M. Gray, G. Milledge and H. Smith; approximately 0.3 km east of Artillery Hill, Sir Bertram Stevens Drive, Royal National Park (34°04'55"S 151°03'40"E), 28 specimens, 6–20 December 1999, collected from pitfall traps, M. Gray, G. Milledge and H. Smith; 3 km northwest of Caledonia Knob, Bagawa State Forest (30°08'44"S 152°55'47"E), 37 specimens, 10–23 November 1999, collected from pitfall traps, M. Gray, G. Milledge and H. Smith. <b>Description</b>. Based on holotype female. <i>Body</i> shape normally laterally compressed; cuticle calcification absent. <i>Eye</i> large (greater than <b> 1</b> ⁄ <b> 3</b> head length). <i>Antenna 2</i> longer than head and first 3 pereonites; peduncular articles narrow. <i>Mandible</i> left lacinia mobilis 4 dentate. <i>Maxilliped</i> outer plate distally acute/arcuate; palp dactylus present and distinct. <i>Pereonite 1</i> sternite without papillose process. <i>Gnathopod 1</i> not sexually dimorphic; simple; merus and carpus not expanded; propodus subrectangular; palm absent; dactylus longer than palm. <i>Gnathopod 2</i> not sexually dimorphic; chelate; narrow; merus and carpus expanded posteriorly; propodus “mitten-like”; palm obtuse; smooth; dactylus shorter than palm. <i>Pereopods 3–7</i> long (½ length of body); simplidactylate. <i>Pereopod 4</i> carpus similar in length to pereopod 3 carpus, dactylus similar to pereopod 3 dactylus. <i>Pereopod 7</i> posterodistal lobe present. <i>Gill 2</i> lobate, not incised. <i>Gills 3–5</i> lobate, smaller than gills 2 and 6. <i>Gill 6</i> lobate, <i> <i>anterior margin convoluted, subapically incised along posterior margin</i>. Oostegites</i> long (length greater than 2× width), weakly setose, setae with simple smooth tips. <i>Epimera 1 to 3</i> not convergent. <i>Epimeron 2</i> subequal in length to epimeron 3. <i>Epimeron 3</i> posteroventral margin smooth, posteroventral corner with small subacute tooth. <i>Pleopod 1</i> well developed, biramous, rami subequal in length to peduncle; inner ramus with 13 articles; outer ramus with 11 articles, <i> <i>outer ramus with more than 10 articles</i>. Pleopod 2</i> well developed, biramous, rami shorter than peduncle; inner ramus with 8 articles; outer ramus with 6 articles. <i>Pleopod 3</i> reduced, uniramous, rami shorter than peduncle; inner ramus with 1 articles; outer ramus without articles. <i>Uropod 1</i> not sexually dimorphic; peduncle with 4 robust setae on peduncle; inner ramus shorter than outer ramus, with 4 robust setae on the margins, with 4 apical robust setae; outer ramus without marginal <b>Etymology</b>. Named for Nana Creek State Forest, the type locality and treated as a noun in apposition. <b>Habitat</b>. Forest floor leaf-litter. <b>Remarks</b>. <i>Arcitalitrus nana</i> is a member of the “sylvaticus” species group. It differs from other species in the group in having a uniramous pleopod 3, in having 3–5 marginal robust setae on the inner ramus of uropod 2 and in having the telson incised halfway. <i>Arcitalitrus nana</i> and <i>Ar. orara</i> both have large eyes. <i>Arcitalitrus nana</i> and <i>Ar. belbucca</i> both have more than 10 dorsal robust setae on the telson and both species, plus <i>Ar. orara</i>, have the inner ramus of uropod 1 shorter than the outer. <i>Arcitalitrus nana</i> and <i>Ar. belbucca</i> and <i>Ar. bassianus</i> all have pleopod 2 outer ramus with 6–10 articles. <b>Distribution</b>. New South Wales: Lowanna, Nana Creek State Forest; Caledonia Knob, Bagawa Creek State Forest; Orara State Forest; Brisbane Water National Park; Dorrigo National Park; Gladstone State Forest; Royal National Park.
description: Published as part of <i>R Peart, 2006, The Amphipod Genus Arcitalitrus (Crustacea: Amphipoda: Talitridae) of New South Wales Forests, With Descriptions of Six New Species, pp. 97-118 in Records of the Australian Museum 58</i> on pages 102-103