CONFIRMATION OF SOIL-FEEDING TERMITES (ISOPTERA, TERMITIDAE, TERMITINAE) IN AUSTRALIA USING STABLE-ISOTOPE RATIOS

1. Carbon (delta(13)C) and nitrogen (delta(15)N) Stable isotope ratios of termites (Isoptera) were examined in Darwin, northern Australia. I t is suggested that the stable isotope technique, together with phylog enetics, is a useful tool to understand the evolution of functional gr oups in detritivores. 2. A high delta(15)N value was observed in the T ermes-Capritermes branch of the subfamily Termitinae and the genus Ami termes, two distinct taxonomic groups that evolved from wood-feeding t o soil-feeding in Australia. Among eight Termes-Capritermes branch spe cies, only two species (Xylochomitermes melvillensis and Ephelotermes melachoma) were discernible as wood/soil interface feeders, the remain ing six species analysed were soil-feeders, where the diet preference was identified by using delta(15)N Of workers. 3. The Termes-Capriterm es group in Australia contains both wood/soil interface feeders and so il-feeders, whereas wood/soil interface feeders in Cameroon are from t he Termes-Capritermes branch while soil-feeders are from Cubitermes gr oup. The result confirmed that soil-feeding forms evolved both in Aust ralia and Africa, but from different phylogenetic groups.