Paleobiogeography of Somalina species during the Middle Eocene in Iran

Genus Somalina silvestri, Test large, up to 30 mm in diameter, discoidal to lenticular, cyclic chambers subdivided into chamberlets as in Orbitolites, with cross-wise oblique stolon system and possibly lateral stolons also, prominent lateral laminae as in Opertorbitolites enclose numerous chamberlets cavities, stolons connect the cavi­ties to the main equatorial chamber layer; wall calcareous, imperforate, porcelaneous; aperture not described as all known speci­mens are embedded in limestone. M. Eocene (Lutetian); Somalia; Iran. Remarks: Asterosomalina was separated on the basis of tests that occurred with typical Somalina but became triaxial or with four or five rays as seen in section. As other species of Somalina and other genera of the Soritidae also include occasional "twinned" or otherwise divided shells, this twinning appears to be related to conditions of growth.

Paleobiogeography, Somalina species, Middle Eocene, Iran