PHYLOGENETIC-RELATIONSHIPS OF BULGARIA INFERRED BY 18S RDNA SEQUENCE-ANALYSIS

Bulgaria has a number of morphological-anatomical and chemical charact ers which are more or less unusual or even unique in the order Leotial es and make a systematic placement difficult. The small subunit riboso mal RNA gene was sequenced and compared with those of 27 euascomycetes . The phylogenetic analysis placed B. inquinans within the cluster of Leotiales and Blumeria (Erysiphales). There it appears as sister to a group which is comprised of Cudonia, Spathularia and Cyttaria. The 18S rDNA data determined so far are unable to give good resolution and bo otstrap support for the relationship between many of the lineages with in the Leotiales/ Erysiphales cluster. Nevertheless, lineages in the L eotiales correlate with different ascus types. Therefore molecular and ascus data are congruent and confirm that in this order characters of ascus apical apparatus are useful as phylogenetic markers at higher s ystematic level (family level or above in the case of Bulgariaceae/ Cy ttariaceae and Helotiaceae/Sclerotiniaceae). The non-molecular as well as the molecular data presented here suggest that Bulgariaceae should be accepted as a family beside Cyttariaceae, Geoglossaceae, Helotiace ae, Leotiaceae, Sclerotiniaceae, discussed in this paper, and some oth ers.