The Palaeoptera Problem: Basal Pterygote Phylogeny

Inferred from 18S and 28S rDNA Sequences

Rasmus Hovmöller,*,† Thomas Pape,† and Mari Källersjö‡

*Department of Zoology, Stockholm University, Stockholm Sweden; and †Department of Entomology and
‡Molecular Systematics Laboratory, Swedish Museum of Natural History, P.O. Box 50007,
SE-104 05 Stockholm, Sweden

Cladistics 18, 313-323 (2002)


Monophyly of the pterygote insects is generally accepted, but the relationships between the three basal branches (Odonata, Ephemeroptera and Neoptera) have remained controversial. The traditional view, to separate the pterygote insects in Palaeoptera (Odonata + Ephemeroptera) and Neoptera, based on the ability or inability to fold the wings over the abdomen, has been questioned. Various authors have used different sets of morphological characters in support of all three possible arrangements of the basal pterygote branches.
We have sequenced 18S and 28S rDNA from 18 species of Odonata, 8 species of Ephemeroptera, two species of Neoptera and one species of Archaeognatha for this study. The new sequences, in combination with sequences from GenBank have been used in a parsimony jackknife analysis resulting in strong support for a monophyletic Palaeoptera. Morphological evidence and the phylogenetic implications for understanding the origin of insect flight are discussed.

Copyright 2002 by The Willi Hennig Society
All rights reserved.