|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Leptaena (Septomena) alaskensis
Strophomenata - Strophomenida - Rafinesquinidae
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|C. M. O. Rasmussen et al. 2012||Shell medium to large, plano-convex, subquardrate to slightly bilobate in outline; shell sharply geniculate dorsally. Maximum width at mid-valve. Anterior commissure uniplicate, sharply geniculate dorsally. Ventral interarea wide and high. Ornament of closely spaced parvicostellate intersected by larger costellae and concentric rugae. Dorsal interior with brachiophores flat and wide. Cardinal process bifid and undercut. Median septum weak with two pairs of transmuscle ridges. Inner pair subparallel, outer pair divergent, shorter, but more pronounced.|