Resolving relationships in some African fungus-growing termites (Termitidae, Macrotermitinae) using molecular phylogeny, morphology, and field parameters

摘要

The Macrotermitinae are a large and successful subfamily of fungus-growing termites, characterised by their symbiotic association with white-rot fungi of the genus Termitomyces. The taxonomy of the subfamily, and in particular of the largest genus Odontotermes, is problematic. We used sequences of the mitochondrial 16S gene from termites occurring in East Africa and Malawi to explore the phyletic relationships within the genus Odontotermes and to place the genus in the broader context of other fungus-growing termites. We also interpret this phylogeny in relation to classical morphological taxonomy in the form of absolute and relative dry weights of the sterile castes, and in relation to innate behaviour as shown by nest architecture and fungus comb structure. This work lays the foundations of a complete taxonomic revision of the Macrotermitinae. The phylogeny supports one clear subdivision, here called the tanganicus group, within the genus Odontotermes. It also supports the significance of field observations on the structure of fungus combs, as the whole tanganicus group builds fungus combs of the sponge type (or modified forms thereof) which are hardly known elsewhere. Other phyletic relationships are less clear, the residual sequences being referred to as the latericius group. We recognise three probable miniature species within the tanganicus group and another possible one in the residual latericius group.