Description of the larva and pupa of Canthochilum histeroides (Harold) with notes on its biology (Coleoptera: Scarabaeidae)

Canthochilum histeroides (Harold) is one of five described species of dung beetles of the subtribe Canthonina (tribe Scarabaeini, or ball rollers) occurring in Puerto Rico. All five species are endemic to Puerto Rico or the Greater Antilles and are the only Scarabaeinae known to occur in Puerto Rico. C. histeroides buries dung balls that are to serve as larval food individually 7-10 cm directly below the dung supply. Only brood balls several weeks old were seen; no trace of a burrow could be seen at that time. The brood balls measure 7 x 8 to 9 x 11 mm, with the longer axis vertical; they are smoothly contoured on the lower half but rough on the upper, probably as a result of the activities of the larva. The brood ball is made of dung with an outer crust of clay soil, which varies greatly in thickness.