Morphological investigation of three Tetramitus spp. which are phylogenetically very closely related: Tetramitus horticolus, Tetramitus russelli n. comb. and Tetramitus pararusselli n. sp.

The addition of T. horticolus, T. russelli and T. pararusselli confirms that the phenotypic definition of the genus Tetramitus is obsolete. Instead the genus can be differentiated by the significant differences from other vahlkampfiid genera in rDNA sequence.