Natatolana oculata ( Vanhöffen, 1914 )

Keable, Stephen J., 2006, Taxonomic Revision of Natatolana (Crustacea: Isopoda: Cirolanidae), Records of the Australian Museum 58 (2), pp. 133-244 : 209

Natatolana oculata ( Vanhöffen, 1914)

Cirolana oculata Vanhöffen, 1914: 499 , fig. 36.– Hale, 1937: 17.– 1952: 26.– Kussakin, 1967: 224.–? Schultz, 1977: 72, figs. 3– 4 [figures labelled C. albinota ]; 1978: 32.

Natatolana oculata .– Bruce, 1986: 222.– Brandt, 1988: 129, figs. 61–65.– Brusca et al., 1995: 82.

Type material. Lectotype designated by Brandt (1988): 3, 21 mm, ZMB 17617 (not examined) . Paralectotypes: ♀, 34 mm, ZMB 17617 (not examined) ; 2♀♀, ZMUC CRU157 —apparently part of the original syntype series from the type locality donated by the ZMB in 1926 (examined). Type locality: off Gauss Station , Posadowsky Bay, Antarctica, 66°2.9'S 89°38.5'E, 385 m, [Deutsche Sudpolarexpedition 1901–1903] .

Material examined. Antarctica: 2♀♀, USNM Acc. No. 247268, Palmer Peninsula, 64°46'S 64°04'W, fish traps, 47.5 m, 5 April, 1963, Staten Island Expedition .

Diagnosis. Interocular furrow: moderately developed, distinct but not extending across the cephalon. Frontal lamina: lateral margins straight, narrowing posteriorly, or lateral margins straight, parallel. Antenna: c. 0.3× as long as body, reaching to half way along pereonite 3. Coxal plates: furrows moderately developed, on all coxae. Pereonite 1, coxa 2 posterior margins straight or slightly convex, or sinuate. Pleonite 4: posterodorsal margin strongly concave proximal to meeting posteroventral margin at apex; apex forming a narrow acute point. Pleotelson: broad, length 0.84× basal width; anterodorsal depression absent; anterolateral margins convex; posterolateral margins concave; apex produced into a small point; with 8–12 RS. Pereopod 2: propodus with 6 RS on palm. Pereopod 3: propodus with 4 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 beyond tip of endopod; margins very slightly curved laterally; slender; apex not at angle to adjacent margins, bluntly rounded. Uropods: exopod subequal to endopod, 0.96× the length of the endopod.

Size. Brandt (1988) states that the maximum length of males is 35 mm and of females 28 mm but also mentions that a paralectotype female is 34 mm.

Remarks. Natatolana oculata is similar to N. meridionalis and N. pastorei . It differs most noticeably from N. meridionalis in having the posterolateral margins of the pleotelson distinctly concave and markedly angled to the anterolateral margins (not convex and joining smoothly with anterolateral margins). Natatolana oculata differs most noticeably from N. pastorei in having the dorsal posterolateral margin of pleonite 2 projecting posterior to the ventral posterolateral margin (not projecting subequal to the ventral margin).

The material of Schultz (1977) from southern Argentina is discussed under remarks for N. meridionalis .

Distribution and ecology. Magellan Strait, South Shetland Islands, Antarctic Peninsula and Weddell Sea ( Brandt, 1988); possibly southern Argentina. At depths of 43.5– 385 m. Scavenger.