They do not have keeled sterna.
Its abdomen is shiny except sparsely pollinose on the 1st segment and sterna; dorsum black pilose; the venter is white pilose except black on the 5th sternum.
The sterna are brownish black.
Terga are separated from each other and from the adjacent sterna or pleura by a membrane.
In the "monotrysian" type there is an opening on the fused segments of the sterna 9 and 10, which act as insemination and oviposition.
The ridge is elongated and ends on anterior sterna, which have a rounded tubercle.
In insects, the sterna are usually single, large sclerites, and external.
The males would press their gastral sterna against a perch and rub their mandibular against it.