Cyclozyga sinusigera Yoo

PI. 16 figs 6-7

Cyclozyga sinusigera Yoo, 1988: 247, figs 92-94.

Dimensions. Figured specimen (F78480): H 1.3 mm, W 0.4 mm .

Additional material. 1 specimen from 'Marohn' (Locality 28).

Stratigraphic position. In upper part of the Dangarfield Formation.

Remarks. This is an extremely rare species. Cyclozyga sp. (PI. 19 figs 5-8) from 'Kyndalyn' resembles C. sinusigera Yoo in shell shape and ornamentation, but differs in having closely spaced collabral lirae on teleoconch. Only two specimens of Cyclozyga sp. are obtained. The systematic position of Cyclozyga was discussed by Knight (1930a), and Hoare & Sturgeon (1978). The North American species of Cyclozyga have more strongly developed revolving costellae and are more attenuate in form.