The cuticular hydrocarbons of the giant soil-burrowing cockroach Macropanesthia rhinoceros Saussure (Blattodea : Blaberidae : Geoscapheinae): analysis with respect to age, sex and location

The cuticular hydrocarbons of a widespread species of soil-burrowing cockro ach, Macropanesthia rhinoceros, have been sampled from most of its known ge ographical locations. Analysis of extracts from individual insects has enab led a study of differences within a population as well as among geographica l locations. In the case of M. rhinoceros, except for newly hatched first-i nstar nymphs, variations in hydrocarbon composition among individuals of di fferent cohorts of nr. rhinoceros, based on age and sex, are no greater tha n those among individuals of a single cohort. Geographical populations of t his species are variable in hydrocarbon composition unless they occur withi n a few kilometres of each other. A few populations showed very different h ydrocarbon patterns but. in the absence of any correlating biological diffe rences, it is uncertain whether this signifies the presence of otherwise un recognizable sibling species or just extreme examples of the geographical v ariation characteristic of this group of insects. (C) 2000 Elsevier Science Inc. All rights reserved.