Neotenic Production in Cryptotermes brevis (Walker): Influence of Geographical Origin, Group Composition, and Maintenance Conditions (Isoptera: Kalotermitidae)

A comparative experiment with groups of mostly brachypterous numphs of C. brevis , oringinating either in America or Australia, revealed significant differences in neotenic production attributable to termite source, group composition, and/or maintenance conditions (especially those involving timber presentation). The differences were mainly in the time required to respond to being orphaned. Australian groups produced more supernumerary neotenics than American ones, but the latter suffered a higher nymphal mortality during the phase of neotenic production. In both groups approximately the same number of surviving nymphs (plus the neotenic pair) resulted, but the mechanisms for regulating the number were different in the two. Apparently the Australian groups allowed a higher expression of the neotenic potential, and regulation (via the killing of supernumary neotenics) occurred after the nymphs had moulted into neotenics.