Beloitoceras sinuoseptatum

Beloitoceras cf. sinuoseptatum (Roemer, 1861) Figs 16G, 32C, 33 Material examined ESTONIA • 2 specs; Vormsi Island, Hosholm shore; Adila Formation, Pirgu Regional Stage; GIT 878- 231, GIT 426-2. Description The nearly complete specimen GIT 878-231 (Fig. 32C) is relatively strongly curved during early growth stages (corresponding to conch heights <ca 40 mm) and reaches a maximum conch height of 53 mm at the base of the mature body chamber. There, the conch width is ca 37 mm (CHI = 1.43), and the conch cross section is oval in shape with narrow dorsal and ventral margins. The body chamber is 35 mm long and at the aperture 48 mm high. In lateral view, the dorsal and ventral margin of the body chamber is slightly convex. The peristome appears to be straight and simple. The phragmocone height increases from 40 mm to 53 mm at a length of 55 mm (angle of expansion = 13°). Between conch heights of 21–40 mm the conch expands at an angle of 19°. The sutures form shallow lateral lobes. In specimen GIT 426-2, which is a short fragment of a phragmocone with five chambers, the details of the siphuncle are well-preserved (Fig. 16G). The siphuncular segments are trapezoidal, with adnate areas at the adapical surfaces of the septa. The septal necks are cyrtochoanitic. Remarks The two specimens are slightly more curved and larger than the fragments assigned to B. sinuoseptatum but otherwise indistinguishable from the types and the material herein assigned to B. sinuoseptatum sensu stricto, in which a maximum conch height of ca 44 mm occurs (see above).