Lentinula madagasikarensis sp. nov., a relative of shiitake mushrooms from Madagascar

Abstract

We describe the first species of Lentinula from Africa, Lentinula madagasikarensis sp. nov. The new taxon, which was collected from central Madagascar, is strikingly similar to L. edodes, the shiitake mushroom. A BLAST search using ITS sequences from L. madagasikarensis as the query retrieves a mix of Lentinula, Gymnopus, Marasmiellus, and other members of Omphalotaceae as the top hits. A 28S phylogeny of the Omphalotaceae confirms placement of L. madagasikarensis within Lentinula. An ITS phylogeny places L. madagasikarensis as the sister group of L. aciculospora, which is a neotropical species. Lentinula madagasikarensis is characterized by robust basidiomata with vinaceous pilei, prominent floccose scales near the pileus margin, florets of sphaeropedunculate cheilocystidia, and subcylindrical basidiospores. This report constitutes a 4 000-mile, trans-oceanic range extension for Lentinula.

Keywords: 1 new taxon; Africa; Omphalotaceae; biogeography; edible mushrooms; systematics.

Fig. 1.

Maximum-likelihood phylogeny of Omphalotaceae based on the 28S sequence dataset of Oliveira et al. (2019) with 788 bootstrap replicates according to autoMRE bootstopping criteria. Major clades from the original study are labeled and collapsed with number of samples included in each clade. BS values ≥ 50 % are included with the branches.

Fig. 2.

Maximum-likelihood phylogeny of Lentinula based on Dataset 2 of ITS. BS values ≥ 50 % / Bayesian PP values ≥ 0.80 are included with the branches. Sequence labels include GenBank accession numbers and collection numbers. G1–G5 in the Asian-Australasian clade correspond to ITS-based groups from Hibbett et al. (1998). Country codes: AUS = Australia, BRA = Brazil, COL = Colombia, CRI = Costa Rica, IND = India, KOR = South Korea, MEX = Mexico, NPL = Nepal, NZL = New Zealand, PHL = Philippines, PNG = Papua New Guinea, POL = Poland (possible cultivar), PRI = Puerto Rico, RUS = Russia, USA = continental USA, VEN = Venezuela.

Fig. 3.

Distance-matrix heat map of representative sequences of species of Lentinula based on pairwise distances from the ITS multi-sequence alignment given as proportion of divergence.

Fig. 4.

A, B. Field photograph of Lentinula madagasikarensis (type specimen, PC coll. BB06.007). C, D. Field photographs of Lentinula madagasikarensis (paratype specimen, PC coll. BB08.120). E. Basidiospores. F. Basidia. G. Cheilocystidia. Scale bars: A–D = 2 cm, E–G = 20 μm.