In: Sydowia 78, (2025): 13-25; ISSN 0082-0598, DOI 10.12905/0380.sydowia78-2025-0013, Published online on April 4th, 2025

Entoloma hygropileum, sp. nov. (Entolomataceae, Basidiomycota) from a ‘brejo de altitude’ forest in Brazil and its Western Gondwana counterpart

Leonardo F. Silva, Ricardo Koroiva & Felipe Wartchow,*

1 Universidade Federal de Pernambuco, Programa de Pós-Graduação em Biologia de Fungos, Av. da Engenharia, s/n, Cidade
Universitária CEP: 50740-570,Recife, PE, Brazil
2 Universidade Federal da Paraíba, Departamento de Engenharia e Meio Ambiente, CEP 58297-000, Rio Tinto, PB, Brazil
3 Universidade Federal da Paraíba, Departamento de Sistemática e Ecologia, CEP 58051-970, João Pessoa, Paraíba, Brazil;
* e-mail: fwartchow@yahoo.com.br

Silva L.F., Koroiva R. & Wartchow J.E. (2025) Entoloma hygropileum, sp. nov. (Entolomataceae, Basidiomycota) from a ‘brejo de altitude’ forest in Brazil and its Western Gondwana counterpart. – Sydowia 78: 13–25.

A new species of Entoloma subg. Entoloma is described from a forest fragment in northeast Brazil.
The species description is based on macro- and micro-anatomical characters of the basidiomata, and molecular phylogenetic analyses of ITS and 28S LSU region of nuclear ribosomal DNA. Entoloma hygropileum, sp. nov., is distinguished by the tricholomatoid to somewhat clitocyboid habit with very moist to almost slimy and glabrous brownish pileus, broadly adnate lamellae with subdecurrent tooth, proportionally short stipe, isodiametric to subisodiametric basidiospores 6.8–8.6 × 6.1–7.6 µm, absence of hymenial cystidia and a callidermic pileipellis. The most similar species is E. djaense that primarily differs in the proportionally much longer stipe and the lamellae attachment. They present a pileipellis construction unique among the genus, suggesting a Western Gondwana distribution.

Keywords: Agaricales, Agaricomycetes, Neotropic, systematics, taxonomy. – 1 new species.