Shell Interior of Semiplanella carinthica Sarytcheva et Legrand-Blain (Brachiopoda, Productida)

Abstract

The interior of the dorsal valve of Semiplanella carinthica Sarytcheva et Legrand-Blain, 1977 is described. The location of the bases of brachial loops and adductor muscles is reconstructed. The unusual arrangement of the adductor scars and brachial loops developed in the result of their rotation that was caused by a strong torsion of the shell and necessity to raise the anterior shell margin over the valve bottom. Similarly structured brachial loops and partly cardinal process is known for Beleutella Litvinovich, 1967 and possibly Talasoproductus Litvinovich et Vorontsova, 1983. These three genera are suggested to be united into a new tribe Semiplanellini tribe nov. of the subfamily Gigantoproductinae.