Taxonomic study of Collybiopsis (Omphalotaceae, Agaricales) in the Republic of Korea with seven new species

Abstract

Collybiopsis is a genus of the gymnopoid/marasmioid complex of the family Omphalotaceae. The classification system of Collybiopsis has recently undergone large changes through molecular approaches. The new classification system has not been applied for Collybiopsis in the Republic of Korea, and general research on this genus was also lacking. In this study, we analyzed the Collybiopsis species in the Republic of Korea by assessing all gymnopoid/marasmioid specimens collected nationwide for ten years by combining morphological approaches and multilocus (ITS + nrLSU) phylogenetic analysis. We thus confirmed that 16 species of Collybiopsis are present in the Republic of Korea, including two previously unreported species (Co. nonnulla and Co. dichroa) and seven new species (Co. albicantipessp. nov., Co. clavicystidiatasp. nov., Co. fulvasp. nov., Co. orientisubnudasp. nov., Co. subumbilicatasp. nov., Co. undulatasp. nov., and Co. vellereasp. nov.). A thorough examination of the Collybiopsis suggested that it is difficult to distinguish or identify the species based on morphological characteristics only; a combined molecular approach is needed for accurate identification. The Collybiopsis database of the Republic of Korea is updated, and information on the new species is provided. Five new combinations from Marasmiellus to Collybiopsis are also proposed (Co. istanbulensiscomb. nov., Co. koreanacomb. nov., Co. omphalodescomb. nov., Co. pseudomphalodescomb. nov., and Co. ramuliciolacomb. nov.).

Collybiopsis pakistanica (Omphalotaceae, Agaricales, Basidiomycota), a new mushroom species from Margalla Hills, Pakistan and two new combinations

“…Our phylogenetic results suggest that two species should be transferred from Gymnopus to genus Collybiopsis , following their recent concept by Petersen and Hughes (2021) and Kim et al (2022) and new combinations are hence proposed as follows.…”

“…In conclusion, we identified Collybiopsis pakistanica as a new species through combined morpho-anatomical and molecular phylogenetic analyses and thus update the Pakistani inventory of Collybiopsis. Moreover, this study provides some additions to the recent studies conducted by Petersen and Hughes (2021) and Kim et al (2022): additional combinations of Gymnopus species under Collybiopsis. Further, this research will also be helpful for further studies on Collybiopsis distribution, identification throughout the world and taxonomic arrangements of gymnophoid/marasmioid mushrooms.…”

“…is the type species of the genus which includes approximately 56 closely‐related taxa (Petersen and Hughes 2021, Kim et al 2022). The species of this genus are characterized by collybioid, marasmielloid, gymnoid, pleutoid and omphaloid basidiocarps, decurrent to free lamellae, central or eccentric stipe with insititions to subinstitions, ellipsoid or oblong basidiospores, hyaline with white spore prints, presence of caulocystidia and diverticulate to collaroid pileal terminal‐elements (Singer 1973, Antonín and Noordeloos 1993, Oliveira et al 2019, Kim et al 2022). Because of their low level of variation in morphological features and relatively uncharacteristic basidiocarp, many marasmioid/gymnopoid species were previously included in Marasmius Fr.…”

“…Collybiopsis is morphologically and phylogenetically close to Gymnopus (Desjardin et al 1999, Mata 2002, Dutta et al 2015), but they can be distinguished by differences in pilepellis terminal elements, lamellae attachment, stipe features, basidiospore and cheilocystidia (Kim et al 2022). However, there are exceptions and some overlap in characters making it difficult to differentiate Collybiopsis from Gymnopus based on morphological features.…”