PHYLOGENETIC POSITION OF AMBLYOSPORA HAZARD AND OLDACRE (MICROSPORA, AMBLYOSPORIDAE) BASED ON SMALL-SUBUNIT RIBOSOMAL-RNA DATA AND ITS IMPLICATION FOR THE EVOLUTION OF THE MICROSPORIDIA

Sequences of the small subunit rRNA genes of Amblyospora californica a nd an Amblyospora sp. from Culex salinarius were determined. These seq uences were compared phylogenetically with 16 other microsporidia. The results suggest Amblyospora forms a sister taxon to the rest of the m icrosporidia examined. The basal position of Amblyospora is discussed with respect to the evolution of microsporidian life cycles. These seq uences represent the longest microsporidian small subunit rRNA genes s equenced to date, 1,359 and 1,358 bp, respectively. Structural feature s and GC content (49% for both) are comparable to those of other micro sporidia which have been sequenced.