Xylodon lanatus complex and other additions to Xylodon

Abstract

Xylodon lanatus and closely related species were studied with molecular and morphological means. This species complex contains six species, two of which we describe as new. Species in the complex have minutely odontioid hymenophore projections that consist of encrusted, firm-walled hyphae and ellipsoid spores. We assign an epitype for X. lanatus, for which ITS and 28S rDNA sequences were obtained, and amend the concept of X. pseudolanatus. The two new species, both well supported in our phylogenetic analyses, are X. afromontanus, found in Eastern Africa, and X. mantiqueirensis, found in southeastern Brazil. We show the phylogenetic affinity of X. echinatus with X. lanatus for the first time, and according to new data the range of the previous species extends to Sunda Archipelago. We provide scanning electron microscopy illustrations of the crystalline deposits on projecting hyphae for the above-mentioned species. The sixth member of the complex is X. kunmingensis. Outside the X. lanatus complex, we report additional sequenced specimens of X. hyphodontinus. A new species, X. neotropicus from South America, related to X. hyphodontinus, is described. We also describe X. gloeocystidiifer from Ecuador as new species. It is characterised by globose/broadly ellipsoid spores, gloeocystidia and capitate cystidia with a resinous cap. The heterotypic names Hyphodontia yunnanensis and Xylodon yunnanensis are considered. We suggest the previous one is a synonym of the latter.