Unroughing the cat’s tongue mushrooms: Four new species of Pseudohydnum from Brazil based on morphological and molecular phylogenetic evidence

ABSTRACT

Pseudohydnum, commonly known as cat’s tongue mushrooms, is a monophyletic assemblage within Auriculariales, which encompasses species with gelatinous basidiomata, spathulate, flabellate, or shell-shaped pileus, hydnoid hymenophore, globose to ellipsoidal basidiospores, and longitudinally cruciate-septate basidia. According to the available literature, 16 species have been described in Pseudohydnum, mostly represented in temperate-boreal forests of the Northern Hemisphere. However, the limited morphological, molecular, and ecological information, especially from the Southern Hemisphere ecosystems, does not presently allow a reliable assessment of its taxonomic boundaries nor provide a complete picture of the species diversity in the genus. In an ongoing effort to examine specimens collected in dense and mixed ombrophilous forest fragments (Atlantic Rainforest domain) from Southeastern and Southern Brazil, additional taxa assigned to Pseudohydnum were identified. Four new species are recognized based mostly on characters of the pileus surface, stipe, hymenium, and basidiospores. Molecular phylogenetic analyses based on nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode), partial nuc rDNA 28S, and partial RNA polymerase II largest subunit (RPB1) sequences supported the description of these new taxa. Here, we propose Pseudohydnum brasiliense, P. brunneovelutinum, P. cupulisnymphae, and P. viridimontanum as new species. Morphological descriptions, line drawings, habitat photos, and comparisons with closely related taxa are provided. A dichotomous key for identification of currently known Southern Hemisphere Pseudohydnum species is presented.

KEYWORDS:

• Agaricomycetes
• Auriculariales
• jelly fungi
• phylogeny
• species diversity
• 4 new taxa

ACKNOWLEDGMENTS

We thank the anonymous reviewers and the editor for critical review and valuable comments and suggestions to improve the manuscript. We also thank the owners of private conservation areas, such as RPPN Portal das Nascentes and RPPN Campo do Zinco. We would like to acknowledge the curation staff at FLOR and SP who facilitated access to some collections for study. We thank Carlos Vidigal Jr. for assistance in the field in Reserva Biológica Augusto Rusch. We are grateful to Thiago Comenale and Jeferson Müller Timm, whose well-documented collections formed a significant component of the material studied.

DISCLOSURE STATEMENT

No potential conflict of interest was reported by the author(s).

SUPPLEMENTARY MATERIAL

Supplemental data for this article can be accessed online at https://doi.org/10.1080/00275514.2024.2363141.

Additional information

Funding

We thank the Fundação de Amparo à Pesquisa do Estado de São Paulo [FAPESP grants 17/25754-9, 18/15677-0 and 2021/09109-1] for financial support, the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the doctoral fellowship to C. C. do Nascimento, and the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for the support provided through the project Universal Funga do Brasil [403547/2023-7], as well as for the Research Productivity grants [314236/2021-0 and 310150/2022-1] to N. Menolli Jr. and E. R. Drechsler-Santos, respectively. G. Alves-Silva, T. K. Cardoso, M. Titton, and E. R. Drechsler-Santos thank PRONEM [CNPq/FAPESC2020TR733] for support.