Natatolana laewilla Bruce, 1986

Keable, Stephen J., 2006, Taxonomic Revision of Natatolana (Crustacea: Isopoda: Cirolanidae), Records of the Australian Museum 58 (2), pp. 133-244 : 196

Natatolana laewilla Bruce, 1986

Natatolana laewilla Bruce, 1986: 85 , figs. 56, 57.– Brusca et al., 1995: 80.– Bruce et al., 2002: 151.

Natatolana leawilla .–Springthorpe & Lowry, 1994: 51 [lapsus].

Type material. Holotype: ♀, AM P33551 . Paratypes: AM P33550, P33552. All examined. Type locality: east of Port Jackson, NSW, Australia, 33°36'S 152°05'E, 1090–1125 m .

Material examined. Queensland: series from off Flynn Reef , 16°37.81'S 146°23.08'E, 1000m, 6–8 Jun. 1993: 1, AM P47300, SEAS QLD-932; 6, AM P47301, SEAS QLD-950 . New South Wales: series from northeast of Coffs Harbour , 1000m, 11–13 Aug. 1993; 15, AM P47302, 30°10.88'S 153°32.21'E, SEAS NSW-877; 7, AM P47303, 30°10.94'S 153°32.27'E, SEAS NSW- 862 . Tasmania: 8, AM P47304, east of Fortescue Bay , 43°08.96'S 145°15.36'E, 1000 m, 8–9 April 1994, SEAS TAS-403 .

Diagnosis. Eyes: vestigial. Interocular furrow: moderately developed, distinct but not extending across the cephalon. Frontal lamina: lateral margins sinuate. Antenna: c. 0.35× as long as body, reaching to posterior of pereonite 3. Coxal plates: furrows variously developed or completely absent on all coxae, if present may be weakly developed on all or only some coxae. Pleonite 4: apex forming a broad acute point. Pleotelson: broad, length 0.81× basal width; anterodorsal depression present; anterolateral margins convex; posterolateral margins convex; apex not produced, lateral margins converging smoothly to a point; with 10 RS. Pereopods 1–6: males with conspicuous elongated RS subequal to propodus on the merus of pereopods 1–3 and extending from the carpus to dactylus of pereopods 4–6. Pereopod 2: propodus with 0–1 RS on palm (the holotype has one robust seta on one side, in the other material examined these setae may be present or absent). Pereopod 3: propodus without RS on palm. Pereopod 7: basis narrow, width 0.46× length; distance between anterior margin and medial carina less than between posterior margin and medial carina; posterior margin with setae along entire length. Penes: present. Pleopod 2 appendix masculina: extending subequal with tip of endopod; slender; margins strongly or very strongly curved laterally; apex not at angle to adjacent margins, bluntly rounded. Uropods: exopod slightly shorter than endopod, 0.82× the length of the endopod.

Variation. Indistinct to well-developed coxal furrows are apparent on all coxae in some type material and the material examined from Queensland. The holotype and some material examined from Queensland has a robust seta on the propodal palm of pereopod 2. Conspicuously elongated robust setae were only present on the merus of pereopods 1–3 and on the carpus of pereopods 4–6 of adult males from Queensland. None of the male specimens in the non-type material examined had the appendix masculina as strongly curved as in the type material .

Sexual dimorphism. Females lack the conspicuously elongated robust setae that may be present on the merus of pereopods 1–3 and on the carpus of pereopods 4–6 of adult males.

Size. In type material females to 9.5 mm, males to 7.5 mm. Non-type material to c. 15 mm.

Remarks. Natatolana laewilla can be separated from all other species in the genus by the reduced eyes and the presence of a distinct dorsal depression on the pleotelson.

Distribution and ecology. Australia: Cairns, Queensland to Tasmania. At depths of 880–1125 m. Scavenger.