Termites and trees: a review of recent advances in termite phylogenetics

Modern termite phylogenetics is critically reviewed, with an emphasis on tree topologies as phylogenetic hypotheses. Studies have especially concentrated on (1) the position of Isoptera among the Dictyoptera and (2) the family group relationships within the Isoptera. The first of these problems is still controversial; although the weight of evidence now suggests that termites are nested within the cockroaches, thus making "Blattaria" as presently constituted paraphyletic. The exact position of termites within the cockroaches is uncertain, although Cryptocercus is the most plausible sister group.¶Family groups relationships are rather better resolved. Mastotermitidae is now generally accepted to be the most basal termite group. Termopsidae, Hodotermitidae and Kalotermitidae are all basal to (Termitidae + Serritermitidae + Rhinotermitidae), although their relative positions within that part of the tree are disputed. Most recent studies support a sister group relationship for Serritermitidae and (Termitidae + Rhinotermitidae). However, no study has yet unambiguously found the Rhinotermitidae monophyletic. The Termitidae are well established as monophyletic and as the most apical termite family. However, within the Termitidae the monophyly of none of the subfamilies is well established, making subfamily level analyses unreliable.¶A number of problem areas are identified: (1) poor taxon sampling is a universal problem, (2) higher taxonomic groupings are often assumed to be monophyletic a priori without adequate support, (3) datasets are collected from different taxa and character systems without consideration of the overall international effort.