I have been following the discussion about the phylogenetic position of the
Echiura and Pogonophora as well as the taxonomic consequences for the
nomenclature of these groups with great interest. I am delighted by the
general interest taken in this topic and by the recent contribution of T.
Nishikawa, J. I. Saiz-Salinas and E. Cutler, that more work needs to be
done on echiurids in particular, since this is precisely the topic of my
current Ph.D. thesis. My main emphasis is on the larval development of the
nervous system in different Echiura in comparison to polychaete nervous
systems in search for shared or dissimilar morphological characters. First
results of immunohistochemical studies on different echiurid larvae are due
to be published soon and give added support for a close affinity between
echiurids and polychaetes.
Furthermore I am in the process of sequencing different mitochondrial and
nuclear genes in order to broaden the database of molecular characters.
As was suggested by T. Nishikawa, J. I. Saiz-Salinas and E. Cutler my
current sequence analysis include species from Bonellidae, Echiuridae
and Urechidae (using the family-level nomenclature of Stephen & Edmonds
for these echiurid subtaxa).
I would be happy to give more detailed information about my current
studies and to discuss my results with anyone interested in the
phylogenetic reevaluation of the Echiura.
With kind regards,
Dipl. Biol. Rene Hessling
<Hessling at biologie.uni-osnabrueck.de>
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