Abstrakt
The phylogenetic placement of Phragmotrichum chailletii in Melanommataceae (Pleosporales) is re-evaluated and its phylogeographic structure is assessed based on a large number of specimens from Europe and North America together with a four-gene (ITS, LSU, RPB2, EF1-& alpha;) dataset. Morphologically, all collections produced identical conidiomata and conidia on the same substrate, which is spruce cones on litter.
Their fruiting season was also similar as they originated from early spring soon after snow melts at a similar range of elevation. However, all isolates collected in Canada and associated with Picea species native to North America, clustered together in a clade separate from collections made in Europe and occurring on host species native to central eastern Europe.
A sibling species, Ph. thornhilliae, is introduced to accommodate this group of isolates using molecular and phylogeographic evidence. One specimen belonging to the novel species was also collected in Switzerland.
Possible scenarios to explain this anomaly are provided and the most likely explanation is an accidental, human mediated introduction.