Ribosomal DNA sequences of Glugea anomala, G-stephani, G-americanus and Spraguea lophii (Microsporidia): phylogenetic reconstruction

The microsporidian species Glugea anomala, G. stephani, G. americanus and S praguea lophii were compared by using sequence data derived from their smal l subunit rDNA genes which were amplified by polymerase chain reaction and directly sequenced. These sequence data and published data of G, atherinae were analyzed and were used to infer a phylogenetic tree. The 5 microsporid ian fish parasites appeared to be closely related. The higher sequence simi larities demonstrated among G. anomala, G. stephani and G. atherinae sugges t that these 3 parasites are in fact only 1 species of Glugea. Moreover, th e higher sequence similarities between S. lophii and G. americanus support the transfer of the latter Glugea species into the genus Spraguea.