Within my master thesis, which will be finished in February 1994 I have focussed on the groundplan of odonate wing venation and on the microsculpture of the pterostigma. In my projected Ph.D. thesis I will combine results from DNA-sequencing of six selected taxa, with a morphological total-evidence data matrix, using all kind of imaginal and larval morphological characters (wing-venation, mouthparts, genitalia, proventriculus etc.). My preliminary results do indicate that ...:

• the Odonatoptera ("Protodonata" & Odonata) are monophyletic.
  
• the Anisoptera are monophyletic, with Petaluridae being the most plesiomorphous family (but there seem to exist no true fossil petalurids!), followed by the Aeshnoidea (Neopetaliidae & Aeshnidae), Gomphidae and the Cordulegastridae s.str.. The Chlorogomphidae are the sistergroup of the Libelluloidea. Within the Libelluloidea the Synthemistidae are the sistergroup of the Corduliidae (incl. Macromiidae) plus Libellulidae (incl. Macrodiplactidae).
  
• the "Anisozygoptera" are paraphyletic, but the Epiophlebiidae are the extant sistergroup of Anisoptera. Most fossil anisozygopteres are successive stemgroup-representatives of the Anisoptera, and many of them are closer to Anisoptera than is Epiophlebia.
  
• the Zygoptera seem to be monophyletic, according to my most recent findings and contrary to all previous expectations. Hemiphlebia might show to be not as archaic as supposed; it is rather the sistergroup of the Lestinoidea only, than of the total Odonata. The Zygoptera consequently are composed of the following monophyletic groups: ((Hemiphlebioidea & Lestinoidea) &(Calopterygoidea & Coenagrionoidea))
  
• Thaumatoneura, Coryphagrion and Pseudolestes are no megapodagrionids. Thaumatoneura seems to be a member of the Calopterygoidea (Thaumatoneuridae); Coryphagrion is the sistergroup of the Pseudostigmatidae (Pseudostigmatoidea, Coryphagrionidae); Pseudolestes is most probably a true amphipterygid and closely related to Rimanella, but only the discovery of its larva could verify this hypothesis.
  
• Fraser's hypothesis of a zygopteroid ancestor of the Odonata almost certainly is wrong! The ancestral odonate was a member of the anisozygopteroid grade. The groundplan of all extant odonates is similar to the fossil genera Tarsophlebia and Tarsophlebiopsis. The fossil Archizygoptera, Protozygotera and Triadophlebioidea

  
  
  

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  PETALURA vol. 1, 1993, p. 20

  
  
  have evolved the zygopteroid habitus by convergence. Permagrion is a protozygoptere and unrelated to the extant Zygoptera. The fossil Meganisoptera are clearly paraphyletic.
  

• although the homologisation of the odonatoid wing-venation according to Riek & Kukalova-Peck is fully supported by my results, their conclusion that the Ephemeroptera are the extant sistergroup of the Odonata is very debateable. Although the evidence is weak and contradictory, at present the alternative hypothesis of Neoptera as sistergroup of the Odonata is definetly more parsimonious. Therefor the taxon Palaeoptera represents a grade rather than a clade.

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