Prothoracic tracheal apparatuses ofAcanthoplus speiseriBrancsik andEnyaliopsiscf.matebelensisPer., are described. The vesicula femoralis for the apparatus of each species differs from the condition considered by Zeuner (1936a) to be typical for the subfamily Hetrodinae to which the two species belong.Acanthoplus speiseripossesses a horn‐shaped apparatus, whileE.cf.matebelensisbears a trumpet‐shaped structure. The horn‐shaped prothoracic tracheal apparatus was previously reported to be a specialized structure in the ‘Bradyporoid group’ of Zeuner (1936a). The trumpet‐shaped apparatus is reported for the first time in the subfamily. The problems of using the prothoracic tracheal apparatus as a taxonomic character in classifying the tettigoniid subfamilies and the implications of the presence of the atypical prothoracic tracheal apparatuses in the Hetrodinae to the classification of the Tettigoniidae ar