Dr. Stephen Tobe's Virtual Laboratory

Diploptera punctata (Pacific Beetle Cockroach)

Diploptera punctata is the main subject of research in this lab. It is widely known for being the only viviparous cockroach in the world (i.e. the embryos are nourished by the mother during development). As well, it is easy to dissect (click for a tutorial) and produces large quantities of juvenile hormone. Thus, they are very useful to studies of insect endocrinology. This lab has been partially responsible for identifying the factors (called allatostatins) that control the synthesis and release of juvenile hormone, and is engaged in studying the evolution and method of action of the allatostatins.

Click to view videos (in .avi format) of our D. punctata mating behaviour (1.9 MB) and giving birth to live young (2.2 MB).

Above: a group of D. punctata going about their business in their natural habitat. Right: female and male. Females are ~18mm long and have a distinctly broad abdomen. Photo from here.

In the Tobe lab in Toronto, we also have some Diploptera that were trapped from a garden within Silpakorn University, Nakorn Pathom Campus, in Thailand. When they arrived in Toronto in January 2003, it was discovered that they were reproductively isolated from the lab population of D. punctata. Studies in this lab are now underway to identify the species.

Representative pictures of the Thai cockroaches are below.