The Systematic Position of Strepsiptera (Insecta)

The Strepsiptera are considered to be a monophyletic order. They show plesiomorphic characters already lost in most of the other holometabolous insects and many very peculiar autapomorphies related to their specialized endoparasitism. A series of non morphological arguments supports this point of view. Clear synapomorphies to other insect orders are absent; possibly the opisthomotorism and the resulting special structure of the metendosternite may be synapomorphies of the Coleoptera. The Strepsiptera thus are considered to be a sister-group of the Coleoptera.