Genus Kelheimia gen. nov.

Derivatio nominis.

After the city of Kelheim that is close to the Saal quarry.

Type species.

Kelheimia triangulata n. sp.; upper Kimmeridgian; South Germany.

Diagnosis.

Shell broadly trochiform, conical, slightly coeloconoid with early whorls more slender than late whorls; early whorls with ornament of intersecting spiral cords and axial ribs; late whorls ornamented with few wide spiral cords; transition from whorl face to base at sharp, angular edge; base slightly convex, covered with spiral cords; aperture large with circular lumen and callous inner lip; growth lines straight, prosocline.

Remarks.

Pyrgotrochus P. Fischer, 1885 and Conotomaria Cox, 1959 have more evenly increasing whorls, a less pronounced ontogenetic sculptural change, a flat base and a selenizone located well above the abapical suture.