Globobulimorpha costata, 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 : 88

Globobulimorpha costata n.sp.

PI. 23 figs 1-7

Description. Shell minute, low-spired globose, fusiform, anomphalous. Protoconch of I-Il,/,) smooth whorls, deviated. Teleoconch of about 3 whorls of thin shell, last whorl embracing much of previous whorls; whorl profile strongly arched; suture deep; ornament consisting of fine prosocline collabral lirae; base rounded. Aperture large, subcircular; columellar lip with a strong siphonal fold; siphonal channel below fold very wide; parietal inductura lacking or narrowly confined to the region close to the columellar, outer lip thin, straight.

Types. Holotype ( F78495 ) and 4 figured paratypes ( F78496 -7).

Type locality. 150 m west of 'Marohn' homestead, on the Scone-Gundy roadside, 4 km south-west of Gundy, NSW (Locality 28).

Stratigraphic position. In bioclastic limestone, upper part of the Dangarfield Formation.

Additional material. 26 specimens from the type locality ( F78507 ) .

Geographic distribution. Type locality only.

Geologic age. Late Tournaisian.

Etymology. Derived from the Latin costatus meaning costate, bearing ribs.

Remarks. This species resembles Strobeus ovalis n.sp., and species of Soleniscus in possessing a columellar fold, but differs in having a thinner shell layer, strongly arched whorls ornamented with fine collabral lirae.