Taylor, J.D., S.T. Williams, E.A. Glover & P. Dyal. 2007. A molecular phylogeny of heterodont bivalves (Mollusca: Bivalvia: Heterodonta): new analyses of 18S and 28S rRNA genes. Zoologica Scripta 36: 587-606. Available electronically.
(click the figure number to see the cladogram)
+-------- Neotrigonia_lamarckii
--+
| +----- Margaritifera_margaritifera
+--+
| +-- Anodonta_cygnea
+--+
+-- Unio_pictorum