Ruiz, C. & Serrano, J. 2006: Molecular phylogeny and systematics of Calathus Bonelli (Coleoptera: Carabidae: Sphodrini) based on mitochondrial cox1–cox2 sequences. — Entomol. Fennica 17: 214–220.
The current subgeneric taxonomy of the genus Calathus is revised according to cox1–cox2 mitochondrial sequences of 44 species representing six subgenera. The subgenus Calathus s. str. was found to be monophyletic, but the subgenus Neocalathus is clearly polyphyletic and should be split into two or more subgenera. The monotypic subgenus Bedelinus appears in an isolated clade. The recent placement of C. rotundatus within the new subgenus Iberocalathus is supported by molecular data, what makes the subgenus Amphigynus to include only the type species C. rotundicollis. The species of the C. granatensis group are within the sister clade of the subgenus Calathus and should be included in a separate subgenus. Finally, the Canarian subgenera Lauricalathus and Trichocalathus are not well differentiated and do not seem to be monophyletic taxa, which suggests the need for a detailed revision.