Overview
Worldwide this is the second largest family and contains about 155 genera and about 1020 species. The family is poorly represented in Australia, although 6 of the 9 subfamilies occur.
Description
Legs often very short; femora and tarsi sometimes without spines. Hind wing with branches of R sometimes reduced to 5 or less; CuA with numerous branches, many going to the plical fold. Visible male tergal glands generally absent. Male subgenital plate asymmetrical or symmetrical, usually bearing a pair of short slender styles, except in the Panesthiinae which lack them. Hook-like genital phallomere on right side. Female subgenital plate broad, rounded, notched or truncate, never bivalvular. Cerci usually short. Only 1 yolk-filled oocyte in each ovariole at ovulation. Except in 4 panesthiine genera which do not form an ootheca, all make an egg case and retract it into a uterus. One viviparous genus (
Diploptera
), remainder ovoviviparous.