MONTEIRO, A.S*; OKAMURA, B.; HOLLAND, P.W.H: Buddenbrockia is a MYXOZOA

Buddenbrockia is a strange vermifom animal, first reported in 1850 by Dumortier and van Beneden within colonies of the freshwater bryozoan Alcyonella (Plumatella) fungosa from Belgium. Its systematic position was not been suggested at the time. Using light microscopy, Schroder (1910) described longitudinal muscle blocks in Buddenbrockia; he proposed the animal to be derived from the nematodes. Since 1910, there has been no further information of relevance to phylogenetic position; indeed, Buddenbrockia is one of the few animals not yet assigned to any phylum! The recent discovery of Buddenbrockia parasites in Hyalinella puntacta from Ohio and Plumatella repens from France has provided fresh material suitable for molecular studies. We sequenced the near complete 18S rDNA from a French Buddenbrockia sample, and smaller region from the US sample. We found high sequence identity to the myxozoan Tetracapsula bryozoides. Our data, together with ultrastructural data (Okamura et al in press), indicate that Buddenbrockia is a myxozoan, and supports the triploblastic (bilaterian) origin of Myxozoa.