Natatolana valida ( Hale, 1940 )

Keable, Stephen J., 2006, Taxonomic Revision of Natatolana (Crustacea: Isopoda: Cirolanidae), Records of the Australian Museum 58 (2), pp. 133-244 : 230

Natatolana valida ( Hale, 1940)

Cirolana valida Hale, 1940: 290 , fig. 2.–Springthorpe & Lowry, 1994: 64.

Natatolana valida .– Bruce, 1981: 958.– 1986: 89, fig. 60.– Brusca et al., 1995: 82.– Bruce et al., 2002: 153.

Type material. Holotype: ♀, 31.0 mm, AM E4814 (examined). Type locality: east of Flinders Island , Bass Strait [Springthorpe & Lowry (1994) give c. 40°S 148°30'E, 366–549 m].

Material examined. New South Wales: 76 including numerous 33 (2 dissected), AM P44412, off Wollongong , 34°33.01'S 151°16.54'E, 400 m, 7–8 May 1993 , SEAS NSW-803. Western Australia: 6♀♀, NTM Cr 007337, NW of Shark Bay, 26°28'S 112°31'E, pot caught, 400 m, CSIRO Fisheries, 28 April 1990 .

Diagnosis. Eyes: well developed; elongate, length c. 2× height. Interocular furrow: well developed, extending across the cephalon. Frontal lamina: lateral margins straight, parallel. Antenna: c. 0.4× as long as body, reaching to posterior of pereonite 3. Coxal plates: furrows variously developed, coxa 2 and 3 with a strongly developed furrow along ventral margin, coxae 4–7 without furrows. Pleonite 4: posterodorsal margin strongly concave proximal to meeting posteroventral margin at apex; apex forming a narrow acute point, or apex slightly rounded. Pleotelson: broad; anterodorsal depression absent; anterolateral margins almost straight and angling posteriorly toward the midline; posterolateral margins straight, markedly angled to anterolateral margins and meeting at an obtuse angle or convex; apex not produced, lateral margins converging smoothly to a point; with 14–20 RS ( Hale (1940) records 20 on the holotype but Bruce (1986) notes that some may have rubbed off since the original description and records 16; in the material examined a total of 14 was most common but this ranged up to 20). Pereopod 2: propodus with 4 RS on palm. Pereopod 3: propodus with 3 RS on palm. Pereopod 7: basis of medium breadth, width 0.5× length; distance between anterior margin and medial carina less than between posterior margin and medial carina; posterior margin with setae completely absent along entire length. Penes: absent. 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, 0.91× the length of the endopod.

Variation. In the material from New South Wales ( AM P44412) the median downbent process at the anterior of the cephalon is more obvious than in the type specimen. Although Bruce (1986) regarded this process as not constituting the rostral process found in other members of the genus it does appear to be homologous to it. Therefore, the anterior margin of the cephalon is not medially recessed as in other genera, such as Aatolana Bruce, 1993 .

Size. Adults to c. 40 mm.

Remarks. This is the first record of a male specimen of Natatolana valida . This species is most readily recognized by the elongate eyes, lack of penes, morphology of the appendix masculina and frontal lamina with a strongly expanded apex.

Distribution and ecology. Australia:of f Shark Bay, Western Australia; off Wollongong, New South Wales; off Flinders Island, Bass Strait. At depths of 400– 600 m. Scavenger.