Zoila chathamensis ( Cernohorsky, 1971 )

Darragh, Thomas A., 2011, A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae), Memoirs of Museum Victoria 68, pp. 1-28 : 5

Zoila chathamensis ( Cernohorsky, 1971)

Figures 1H , 5A , D-G, I-K

Bernaya chathamensis Cernohorsky, 1971, p. 117 , fig. 13.

Description. Shell of small size for genus (36 mm), solid, somewhat globose to subpyriform, dorsal surface uniformly convex, ventral surface weakly convex, almost flat. Posterior canal narrow, barely projecting, deeply incised; anterior canal very short, deeply incised. Spire not visible. Outer lip with 14– 16 teeth, columella lip with 12–18 teeth. Fossula well developed, smooth, broad, very slightly concave, slightly projecting, bounded by very weak terminal ridge.

Dimensions.

Type locality. Flowerpot Harbour , Pitt Island , Chatham Islands, New Zealand, Red Bluff Tuff , late Paleocene /early Eocene .

Occurrence and material. Pitt Island , New Zealand: Red Bluff Tuff, Flowerpot Harbour (holotype AMNZ TM-1325 ), ( GNS GS12159 , one specimen) ; Red Bluff Tuff, GS 12173 Rocky side, Tarawhenua Peninsula ( GNS TM8792 , one specimen) .

Remarks. Cernohorsky (1971) assigned his new species to the genus Bernaya , apparently not realising that the fossula of species assigned to that genus has a deep groove at the anterior end. His description of the fossula is quite accurate, but his figure does not show the morphology of the fossula very well, as it was not fully prepared. The holotype is refigured here, but the fossula is not very clear in the illustration (fig. 5I). Another specimen kindly provided by Dr Alan Beu has been more fully prepared and although the aperture is narrow, making photography, difficult the simple nature of the fossula can be seen (fig. 5J). The fossula is somewhat similar to that in Z. viathomsoni n. sp. and Z. decipiens (E.A. Smith, 1880), but is not as concave.

Although much smaller, the overall morphology of this species is somewhat similar to that of Zoila friendii thersites ( Gaskoin, 1849) . The fossula is relatively shorter and is not as deeply concave as that of the latter species, but is otherwise similar.

Figures

Figure 1. A, Cypraeorbis medius (Deshayes,1835), × 5;B, Cypraeorbis sphaeroides (Conrad,1848),× 5; C, Cypraeorbis ventripotens (Cossmann, 1903), × 5; D, Cypraeorbis viathomsoni sp. nov. WAM 72.296, × 5; E, Zoila didymorhyncha sp. nov. P302687, × 2.6; F, Zoila campestris sp. nov. WAM 89.437, × 2.6; G, Zoila fodinata sp. nov. WAM 89.637, × 3; H, Zoila chathamensis (Cernohorsky, 1971) GNSTM 87922, × 2.3. Arrows indicate the location of the notch.

Figure 5. A, D–G, I–K, Zoila chathamensis; A, E, I, holotype, AIM 71325, Flower Pot Harbour, Chatham Islands; A, E, × 1.5; I, × 2; D, F–G, J–K, GNS TM8792, Taruwhenua Peninsula, Chatham Islands; D, F–G, K, × 1.5; J, × 2; B–C, H, L, Z. viathomsoni; B–C, H, holotype, WAM 72.296, Thomson Highway, Western Australia; L, fossula, P310194, Thomson Highway, × 3.

Dimensions.