Galiellalactone and its biogenetic precursors as chemotaxonomic markers of the Sarcosomataceae (Ascomycota)

(-)-Galiellalactone is a hexaketide metabolite with interesting pharmacological activities which was detected in four strains of Galiella rufa (Sarcosomataceae, Ascomycota) and in two unidentified fungi shown by their 18S rDNA sequences also to belong to the Sarcosomataceae. These were a wood-inhabiting apothecial species from Chile and an endophytic isolate from Cistus salviifolius (Sardinia). Other members of the family (Urnula helvelloides, one Strumella coryneoidea isolate) produced no galiellalactone but merely hexaketides structurally related to galiellalactone precursors, whereas a third group of species (Sarcosoma latahensis, Strumella griseola, one S. coryneoidea isolate) lacked hexaketide production altogether. Despite thorough screening programmes, galiellalactone and its precursors have not yet been found in any fungus outside the Sarcosomataceae and may thus be a chemotaxonomic marker of the family, supporting its current phylogenetic definition. Two pentaketide derivatives of the 6-pentyl-alpha-pyrone type were found in all G. rufa strains as well as in A111-95 and the hexaketide-producing S. coryneoidea isolate.     

Chorioactidaceae: a new family in the Pezizales (Ascomycota) with four genera

Molecular phylogenetic and comparative morphological studies provide evidence for the recognition of a new family, Chorioactidaceae, in the Pezizales. Four genera are placed in the family: Chorioactis, Desmazierella, Neournula, and Wolfina. Based on parsimony, likelihood, and Bayesian analyses of LSU, SSU, and RPB2 sequence data, Chorioactidaceae represents a sister clade to the Sarcosomataceae, to which some of these taxa were previously referred. Morphologically these genera are similar in pigmentation, excipular construction, and asci, which mostly have terminal opercula and rounded, sometimes forked, bases without croziers. Ascospores have cyanophilic walls or cyanophilic surface ornamentation in the form of ridges or warts. So far as is known the ascospores and the cells of the paraphyses of all species are multinucleate. The six species recognized in these four genera all have limited geographical distributions in the northern hemisphere.