Natatolana narica ( Bowman, 1971 )

Keable, Stephen J., 2006, Taxonomic Revision of Natatolana (Crustacea: Isopoda: Cirolanidae), Records of the Australian Museum 58 (2), pp. 133-244 : 203

Natatolana narica ( Bowman, 1971)

Cirolana narica Bowman, 1971: 107 , figs. 1–22.

Natatolana narica .– Bruce, 1981: 958.– 1986: 64, 222.– Brusca et al., 1995: 82.

Type material. Holotype: 3, 21.8 mm, ZMUA Is. 100.527 . Paratypes: 3, 21.9 mm, USNM 139048 ;? ♀, 17.3 mm , ZMUA Is. 100.528. None examined. Type locality: Banks Peninsula, South Island, New Zealand [43°50'S 173°E], from vestibular diverticulum of Cephalorhynchus hectori .

Material examined. New Zealand: 3, 3♀♀, QM W18895, [Tasman Bay ], 41.18°S, 173.16°E, 0 m, isopod trap, ex New Zealand Oceanographic Institute, K 225A; 3 , ♀, NMNZ Cr 4434, Otago Harbour , 20.3 m, 23 Feb. 1962, loc. 10520 .

Diagnosis. Eyes: vestigial (ommatidia are indistinct and lack pigment). Interocular furrow: well developed, forming a ridge that extends across the cephalon; smoothly convex. Frontal lamina: lateral margins medially constricted. Antenna: c. 0.3–0.4× as long as body, reaching to threequarters of the way along pereonite 4. Coxal plates: furrows variously developed, incomplete and indistinct on coxae 2–4, 7. Pleonite 4: posterodorsal margin strongly concave proximal to meeting posteroventral margin at apex; apex forming a narrow acute point. Pleotelson: broad, length 0.75× basal width; anterodorsal depression absent; anterolateral margins almost straight and angling posteriorly toward the midline, or convex; posterolateral margins broadly rounded; apex not produced, truncate with a small medial point; with 8–12 RS (material examined 8–10, types described as having about 12). Pereopod 2: propodus with 0–1 RS on palm. Pereopod 3: propodus without RS on palm. Pereopod 7: basis broad, width 0.56× length; distance between anterior margin and medial carina less than between posterior margin and medial carina; posterior margin with setae on proximal third. Penes: absent. Pleopod 2 appendix masculina: extending beyond tip of endopod, 1.06× length of endopod; margins straight or very slightly curved laterally; slender; apex not at angle to adjacent margins, bluntly rounded. Uropods: exopod longer than endopod, 1.15× the length of the endopod.

Size. Adults to c. 21 mm.

Remarks. Natatolana narica and N. paranarica n.sp. are the only species of Natatolana in which the uropod exopod is distinctly longer than the endopod. Natatolana paranarica is almost identical to N. narica but differs in that the posterolateral margins of the pleotelson meet at an acute angle, rather than being broadly rounded; the uropod endopod medial margin is smoothly convex, not sinuate; the ventral margin of the posterior coxae is straight not sinuate; there are slender setae at the uropod endopod and exopod apices that are shorter than the length of these rami, rather than being as long as them.

Distribution and ecology. New Zealand. Intertidal to 20.3m depth. Natatolana narica has been collected from nasal tract of a dolphin, it is unlikely to be a parasite as entry probably occurred while the dolphin was dead or dying ( Bowman, 1971) and the species is likely to be a scavenger.