Petrobrasia vallata Krömmelbein & Weber, 1971

Fig. 11, 11a–c

1971 Petrobrasia vallata n. sp. —Krömmelbein & Weber, p. 42–43, pl. 7, fig. 32.

Diagnosis: A Petrobrasia species from the diversicostata -group with the following peculiarities: carapace in lateral outline well rounded, the posterior margin fairly bluntly truncated. Sculpture: a hook-shaped ridge accompanies the ventral margin for its entire length, turns off sharply in the antero-dorsal direction at the posterior margin and ends just before the centre of the valve. The area of the central muscle-field can be raised like a knob or short ridge (mostly on the right valve). The hook-shaped ridge encloses the central valve area, which is embellished with irregularly reticulate, slightly bent or sharply bent longitudinal ribs.

Holotype: Carapace, BfB 7805.

Paratypes: Not deposited.

Dimensions: Holotype, length 0.77mm, height 0.40mm, width 0.21mm.