A reader wants to know, “Does the Madagascar Hissing Cockroach, Gromphadorhina portentosa, exhibit isolation syndrome noted for German and American Cockroaches?” I don’t know the answer to that question off hand. Perhaps someone can comment on this question.
The Madagascar Hissing Cockroaches are clearly social. A male will guard a territory that often contains multiple females and will displace competing males from the territory. The immatures will aggregate near the female for an extended period after their birth. The female Madagascar Cockroach incubates her egg case (ootheca) inside her reproductive system until giving live birth. After birth, females have been observed (Perry and Nalepa) secreting a liquid that is consumed by the hatchlings. I do not know that mothers provide additional substance to their offspring after the initial day. I do not know of studies that have compared growth rates of the immatures held in isolation to group living. It would make an interesting project.
Madagascar “Hissing” Cockroaches
Living With Insects Blog 