Psfudozygopleura gracilis, Yoo, 1994

Yoo, E. K., 1994, Early Carboniferous Gastropoda from the Tamworth Belt, New South Wales, Australia, Records of the Australian Museum 46 (1), pp. 63-120 : 85

PSfudozygopleura gracilis n.sp.

PI. 16 figs 10-11

Description. Shell minute, slender, high spired, many whorled, anomphalous. Protoconch of about 3 whorls, the first whorl smooth, and the others with deeply sinuated transverse costae, transition from protoconch to teleoconch abrupt. Teleoconch of about 7 whorls; whorl profile rounded and somewhat pendant, suture moderately deep, surface smooth or ornamented by faint growth lines. Aperture circular in shape; inner lip thin, reflexed; parietal wall lacking, outer lip sharp with only a very slight sinus, nearly straight; base rounded.

Dimensions. Holotype ( F78483 ): H 1.5 mm, W 0.5 mm, PA20 Q, NW 9 .

Types. Holotype ( F78483 ) and 1 paratype ( F78493 ).

Type locality..Behind 'Kyndalyn' homestead, 10 km south-west of Somerton, NSW (Locality 24).

Stratigrapbic position. In base of oolitic limestone in the Kyncialyn Mudstone Member of the Merlewood Formation.

Geographic distribution. Type locality only.

Geological age. Middle or late Visean.

Etymology. Derived from the Latin gracilis meaning slender, slim.

Remarks. This is a very rare species. Two specimens recovered for this study are characterised by the presence of the typical pseudozygopleurid protoconch, tall smooth teleoconch whorls which are almost symmetrically arched, and a circular shape of aperture. There is no other form comparable to this species.