Beloitoceras undetermined Foerste 1924

Beloitoceras (?) sp. Fig. 28F, I–J Material examined ESTONIA • 1 spec.; Raplamaa, Pirgu River outcrops; Adila Formation, Pirgu Regional Stage, GIT 426- 1081. Description The specimen is a fragment of a nearly complete body chamber and part of a phragmocone. The conch is slightly exogastrically curved. The height and width of the 23 mm long phragmocone are 20–23 mm and 13.5–15 mm, respectively (angle of expansion = 8°; CHI = 1.4–1.5). The septa form wide lateral lobes and pointed angular saddles on the prosiphuncular side. The siphuncle is nearly marginal, empty and the septal foramen has a diameter of 1 mm at the apical end of the specimen (RSH = 0.05). The body chamber is slightly gibbous, reaching its greatest height of 24 mm at ca mid-length of the preserved part. Its preserved length is ca 25 mm. Remarks The relatively long and slender (but still gibbous) body chamber distinguishes this specimen from known species of Beloitoceras. Its uniqueness would justify the erection of a new species and genus. Alternatively, the specimen is related to Richardsonoceroides Kröger, Zhang & Isakar, 2009, or Richardsonoceras priscum (Eichwald, 1860) (see below). However, knowledge about the shape of the complete mature body chamber and information on the siphuncle is needed for a definitive determination. The specimen therefore is left in open nomenclature.