THE PHYLOGENY OF THE CAELIFERA (INSECTA, ORTHOPTERA) AS DEDUCED FROM MTRRNA GENE-SEQUENCES

Fragments of both mitochondrial ribosomal RNA genes of 32 caeliferan t axa (representing six of the seven superfamilies) and six outgroup Ort hopteroids were sequenced. The combined alignment length was 630 bp af ter removal of all ambiguously aligned positions. Separation of the ba sal taxa was problematic and analysis using the LogDet transformation indicated that shared base composition biases were a confounding facto r, The suborder Caelifera and all traditional caeliferan superfamilies except the Pamphagoidea are retrieved as monophyletic groups, though the Eumastacoidea lack significant bootstrap support. Of the tradition al pamphagoid taxa, the Pamphagidae is embedded between classically ac ridid subfamilies, whereas Pyrgomorphidae is placed close to the Pneum oroidea. The morphological similarities of the Pyrgomorphidae and Pamp hagidae may thus be homoplasic. A consensus tree based on five differe nt methods of analysis indicated the following order: (Tridactyloidea, Tetrigoidea (Eumastacidae, Proscopiidae (Pneumoridae, Pyrgomorphidae (Acrididae + Pamphagidae)))). (C) 1997 Academic Press.