Nowrarcturus jamesi, Poore, 2013

Poore, Gary C. B., 2013, Rectarcturidae Poore, 2001 rediagnosed with descriptions of new Australian genera and species (Isopoda: Valvifera), Memoirs of Museum Victoria 70, pp. 17-36 : 23

publication ID	https://doi.org/ 10.24199/j.mmv.2013.70.03
publication LSID	urn:lsid:zoobank.org:pub:84546808-FAA2-4838-BFBD-4D3582415F45
DOI	https://doi.org/10.5281/zenodo.10886581
persistent identifier	https://treatment.plazi.org/id/1C749725-DF07-48BB-8B5A-7364487E1812
taxon LSID	lsid:zoobank.org:act:1C749725-DF07-48BB-8B5A-7364487E1812
treatment provided by	Felipe
scientific name	Nowrarcturus jamesi
status	sp. nov.

Treatment

Nowrarcturus jamesi View in CoL sp. nov.

Zoobank LSID. http://zoobank.org/ urn:lsid:zoobank.org:act:

1C749725-DF07-48BB-8B5A-7364487E1812

Figures 1a View Figure 1 , 4–6 View Figure 4 View Figure 5 View Figure 6

Material examined. Holotype. Australia, NSW, 54 km ESE of Nowra (34°52.7'S, 151°15.04'E), 990–996 m, 22 Oct 1988 (stn SLOPE 53 ), NMV J23444 About NMV (male, 6.3 mm). GoogleMaps

Paratypes. Collected with holotype. NMV J23734 About NMV (ovigerous female, 6.5 mm); NMV J19188 About NMV (1 male, 2 females, 1 manca); J19747 (ovigerous female, 6.5 mm) .

NSW, off Nowra (34°52.3'S, 151°15.0'E), 1096–1118 m, 15 Jul 1986 (stn SLOPE 7 ), NMV J19187 About NMV (male, 6.0 mm; female, 4.8 mm). GoogleMaps (All collected by WHOI epibenthic sled by G.C.B. Poore et al., Museum Victoria.) E of Broken Bay (33°36'S, 152°09'E), 1097 m, 4 Dec 1979 (stn K79-20-07), AM P.32672 (male, 6.0 mm) GoogleMaps .

Description. Male. Of even dimensions throughout length, sparsely and microscopically pustulose between transverse ridges, 3.2 times as long as greatest width. Pleotelson 0.25 times total body length.

Head with 3 pairs of submedian dorsal blunt tubercles: first conical, second broader, third ridge-like, all simple; maxillipedal segment with simple transverse ridge; ventrolateral margin smooth, with anterior triangular projection. Pereonites 1–7 each with pair of submedian and pair of sublateral blunt tubercles on transverse ridge. Submedian and sublateral tubercles on pereonites 1 and 2 secondarily pustulose; submedian processes on pereonite 3 flat transversely, anteriorly curved, meeting as shallow notch. Pereonites 1–7 + maxillipedal segment with supracoxal tubercles, weaker on 5–7. Pereonites 3 and 4 with sharp, bilobed, middorsal, transverse, posteriorly sloped ridge anterior to main ridge (less well defined on 4). Pleonites 1 and 2 with obsolete lateral bosses; pleonite 3 domed middorsally, with rounded marginal lobes; posterior pleotelson evenly domed, with rounded lateral wings; pleotelson tapering evenly to sharply rounded apex, tapered section 0.7 times as long as wide.

Antennule flagellum article 1 with 3 pairs plus 1 aesthetascs, article 2 with 2 aesthetascs. Antenna, fused articles (1 + 2) short, stout, with ventrolateral flange; article 5 1.5 times length of article 4; flagellum of 3 articles, almost as long as peduncle article 5.

Pereopod 1 propodus 2.5 times as long as wide. Pereopod 2 tuberculate, especially basis and flexor margin of carpus; dactylus unguis 1.2 times length of dactylus body. Pereopod 4 dactylus body 1.4 times as long as propodus, unguis setiform, 0.5 times length of dactylus body. Pereopods 5–7 with several small tubercles on extensor margin of basis–carpus. Pereopod 7 dactylus body 0.6 times as long as propodus, unguis stout, 0.5 times length of dactylus body.

Male pleopod 1 exopod 4 times as long as basal width; posterior face with 2 longitudinal erect lobes parallel to groove; lateral margin bearing row of 8 long simple setae proximally, 11 short simple setae distally; distomesial seta-bearing lamina well separated from much longer apex by triangular notch.

Uropodal exopod 0.7 times length of endopod.

Ovigerous female. Pereonites 2–4 swollen, taller and broader than more anterior and posterior segments. Submedian processes on pereonite 3 flat transversely, anteriorly curved, overhanging, meeting as a deep notch, and opposing a pair of more anterior erect submedian tubercles. Oostegites 1–4 supported by oval coxal plates; oostegites 5 a pair of adjacent oval discs.

Distribution. Southern NSW, Australia, 34– 42°S, 990–1118 m depth.

Etymology. For my grandson, James Salter.

Remarks. Females of the new species are immediately recognisable by the dorsal sculpture, particularly the characteristic submedian ridges and lobes on pereonite 3. This structure is less well developed in males.