Charactoceras? sp.

Fig. 22B

Material examined

ESTONIA • 1 spec.; Paope quarry; Kõrgessaare Formation, Vormsi Regional Stage; TUG 1006-13 .

Description

The specimen is a ca 120° long fragment of a body chamber with a broad elliptical whorl cross section. The dorsal part of the whorl is not preserved. The fragment has a shallow annulations, which run nearly directly transverse over the umbilical margin, ca 19–20 annulations occur per volution. A shallow U-shaped hyponomic sinus is apparent both from faint growth lines preserved on the mold and the shape of the annulations. The preserved part of the conch has a maximum diameter of 52 mm, and the diameter of the preceding whorl is 33 mm (WER = 2.48); at its adoral end the whorl width is 18 mm and the corresponding whorl height is 16 mm (WWI = 1.13).

Remarks

The conch shape and ornamentation of this fragmentary specimen is similar to annulated species of Charactoceras, such as C. kallholnense Frye, 1982 or C. suecicum Frye, 1982, However, the siphuncle including the septal foramen are not preserved, making a genus determination uncertain, and the fragmentary character of this specimen does not permit species level determination.