In dixid and some culicid males, a transverse lobiform element of the phallosome located between the phallus and proctiger; supported on either side by a sclerite, opisthophallic sclerite. The opisthophallus has not been studied or recognised in most mosquitoes but is well developed in Culex, Maorigoeldia and Verrallina.
Adults: opisthophallus