Contributions to Zoology, 70 (3) 127-138 (2001) SPB Academic Publishing bv, The Hague Soil-dwelling polychaetes: enigmatic as ever? Some hints on their phylogenetic relationships as suggested by a maximum parsimony analysis of 18S rRNA gene sequences ³ Emilia Rota Patrick Martin² & Christer Erséus ¹, 1 di Dipartimento Biologia Evolutivei. Universitd di Siena, via P. A. Mattioli 4. IT-53100 Siena, Italy, e-mail: 2 Institut des Sciences naturelles de des
[email protected]; royal Belgique, Biologic Eaux donees, 29 rue Vautier, B-1000 e-mail: 3 Bruxelles, Belgium,
[email protected]; Department of Invertebrate Zoology, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden, e-mail:
[email protected] Keywords: Terrestrial Polychaeta, Parergodrilus heideri, Stygocapitella subterranea, Hrabeiella I8S rRNA periglandulata, gene, molecular phylogeny, rapid radiation Abstract Collectionof new specimens 130 DNA extraction, amplification and sequencing 130 Alignment To re-evaluate 130 the various hypotheses on the systematic position of Phylogenetic analyses 130 Parergodrilus heideri Reisinger, 1925 and Hrabeiella Results 132 periglandulata Pizl & Chalupský, 1984,the sole truly terrestrial Discussion 132 non-clitellateannelidsknown to date, their phylogenetic relation- ships Acknowledgements 136 were investigated using a data set of new 18S rDNA References 136 of sequences these and other five relevant annelid taxa, including an unknown of species Ctenodrilidae, as well as homologous sequences available for 18 already polychaetes, one aphano- neuran, 11 clitellates, two pogonophorans, one echiuran, one Introduction sipunculan, three molluscs and two arthropods. Two different alignments were constructed, according to analgorithmic method terrestrial forms constitute (Clustal Truly a tiny minority W) and on the basis of a secondary structure model non-clitellate annelids, (DCSE), A maximum parsimony analysis was performed with among only represented by arthropods asan unambiguous outgroup.