Relationships of Halosarpheia, Lignincola and Nais inferred from partial 18S rDNA

Cladistic analysis was performed on partial sequences from the nuclear-enco ded small subunit ribosomal DNA. Four Halosarpheia spp., Lignincola laevis and Nais inornata were examined to determine the placement of these genera within the unitunicate ascomycetes. Two equally most parsimonious cladogram s resulted from the analysis of the data. In a strict consensus of the two cladograms the taxa sampled did not form a monophyletic group, and Halosarp heia was shown to be polyphyletic. The marine Halosphaeriales formed a subc lade with taxa from the Microascales. Data indicate that L. laevis and N. i nornata may be congeneric, but other species of both genera require further study.