Zoila campestris, Darragh, 2011

Darragh, Thomas A., 2011, A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae), Memoirs of Museum Victoria 68, pp. 1-28 : 24-26

Zoila campestris sp. nov.

Figures 16A–B, E–J, O

Cypraea (Zoila) sp. Ludbrook, 1978, p. 129, pl. 13, fig. 19.

Zoila sp. Wilson and Clarkson, 2004: 52, pl. 55, figs a, b.

Description. Shell solid, polished, of average size for genus, globose, surface on some specimens malleated with rectangular depressions, with sides about 1.5 mm long; ventral surface flattened. Spire barely protruding beyond last whorl, covered with thick callus. Posterior canal short, notched, sides thickened. Anterior canal very short, abruptly truncated, deeply incised. Aperture sinuous, widened above fossula; outer lip with 17–24 well-developed teeth, extending along entire lip; inner lip with 17–21 well-developed teeth, extending along entire lip. Fossula well developed, deeply depressed, bounded anteriorly by sharp terminal ridge. Colour pattern present on some specimens, of brown ground with darker brown patches.

Dimensions.

Type locality. Quarry 2.5 km north of Hampton microwave repeater tower, Roe Plains , Western Australia. AMG Eucla l:250,000 sheet CK365465. Roe Calcarenite .

Type material. Holotype WAM 89.177 , collected G.W. Kendrick 27–30 October 1988; paratype WAM 89.437 , collected Sam Rowe, January 1989; paratype NMV P308704 , collected T. A. Darragh, 9 August 1973.

Time range. Pliocene.

Occurrence and material. Roe Calcarenite : PL3172 Hampton Tower (P308704-5, WAM 69.494 , 70.17 , six specimens); PL3167 1.5 km north of Hampton Tower (P308703, WAM 80.109 , three specimens); PL3166 2.5 km north of Hampton Tower (P121293, WAM 89.178 , 89.437 , 89.637 , four specimens) .

Remarks. At first glance, small specimens of this species may be confused with the common Austrocypraea amae Fehse and Kendrick of the Roe Calcarenite, but they are readily distinguished by their smooth fossula. In Austrocypraea , the columellar teeth are produced into thin ribs that continue across the fossula. This species is most closely related to the living species Zoila decipiens ( Smith, 1880) , Recent, Western Australia, from which it differs by having stronger teeth and teeth present along the entire columella. It is also globose in shape rather than pyriform as in Z. decipiens and lacks the prominent protruding spire of that species. The fossula is very similar to that of the Z. decipiens . It is not closely similar to the fossil species of Zoila known from the Oligocene and Miocene of southeast Australia, with the exception of a species known from a single broken specimen from the upper Miocene of Victoria. Z. campestris bears some resemblence to Zoila kendengensis Schilder, 1941 from the Pleistocene Putiangan Formation of Java, but that species has relatively prominent anterior and posterior canals.

Etymology. Latin campester, pertaining to a plain.

Figures

Figure 16. A–B, E–J, O, Zoila campestris; A–B, paratype, WAM 89.437, Roe Plain, Western Australia, uncoated to show colour pattern, × 1; E, J, O, paratype, P308704, Roe Plain, × 1; F–H, holotype, WAM 89.177, Roe Plain, × 1; C–D, M, Z. sp., WAM 82.549, Barrow Island, Western Australia, × 1; K–L, N, Z. fodinata, holotype, WAM 89.637, Roe Plain, Western Australia, × 1.

Dimensions.