New insights on Hygrophorus penarioides and H. penarius (Agaricales, Hygrophoraceae) from Hungary

The ectomycorrhiza forming basidiomycete Hygrophorus penarius sensu lato was recognized as two species, H. penarioides and H. penarius in 2007 based on molecular and morphological evidence. However, this was based on few collections of restricted geographical origin and no studies have performed molecular analysis on additional specimens to date.To this end we sequenced the nrDNA ITS regions of 29 H. penarius s. l. collections from Hungary and Slovakia and analysed with collections from previous studies. Bayesian and Maximum Likelihood phylogenetic analyses confirmed the separation of H. penarioides and H. penarius in two clades with the majority of the specimens belonging to H. penarioides and only three to H. penarius. Despite the strong support of the lineages, there was no coherent difference in basidiome and spore traits. We also provide the first evidence of an intraspecific nrDNA sequence variation in the ITS2 region of H. penarioides together with morphological variability that has not been reported to date.On the basis of our result, we conclude that the Quercus associated H. penarioides is far more common in Hungary than the Fagus associated H. penarius and we suggest that identification of the two species in the absence of DNA sequence analysis should be handled with caution, especially when herbarium specimens are examined.

Is There Such a Thing as Kalmia × Rhododendron?

Two putative hybrids between Kalmia and Rhododendron, their suspected progenitor species and related taxa were submitted to DNA sequencing of cpDNA trnL-F and nrDNA ITS regions in order to test whether there was DNA sequence evidence both for hybridization per se and for the direction of the cross should one be evident. Comparison of eight DNA sequences from these putative hybrids with Rhododendron and Kalmia species showed clear evidence of origin within Rhododendron. No evidence of Kalmia DNA was detected. These putative intergeneric hybrids appear to be mutants of Rhododendron and not of hybrid origin.