Clavulina ossea Meiras-Ottoni & Gibertoni

MycoBank number: MB 818103 Facesoffungi number: FoF 2956

Etymology: ossea (Latin) = bone, referring to appearance basidiomata after drying.

Holotype: URM 89970

Basidiomata branched, solitary or in small groups, with fleshy consistency, ‒10 cm, polychotomous branches, the tips of branches are unique or rarely cristate, becoming dark, stem visible, sterile, when fresh dark brown (8F6), branches brownish-lilac grey (10C2, 16B2), hymenium amphigenous starting just below the branch point and extending to the apex of the branches. Basidiospores globose to subglobose, 6‒9 (L = 7.66) × 5‒7.5 (W = 6.56) μm, Q = 1.14, smooth, hyaline, with one large oleiferous guttule, thin-walled, with short apiculus (0.2‒1 μm), IKI-. Hyphal system monomitic, tramal hyphae smooth sometimes verrucous, parallel, hyaline, 3–10 μm, some hyphae are wide but not inflated, clamp connections abundant, subhymenium tightly interwoven. Cystidia absent. Basidia cylindrical, 21‒44 × 5‒6 μm, hyaline, multi-guttulate, with 2 cornute sterigmata, 4–5 μm, postpartal septa observed on most basidia.

Material examined: BRAZIL, Paraíba: Areia, Parque Estadual Mata do Pau-Ferro, June 2015, C.O. Mendonça (URM 89970, holotype; isotype in O). GenBank number ITS:KX811197.

Notes: This species is characterized by the robust, fleshy, and pale lilac basidiomata when fresh, resembling bones when dry, and hyphae occasionally incrusted. The new species is composed of several solitary or in pairs basidiomata, scattered on soil covered by rotten leaves and branches. Of the species of Clavulina with similar colour (vinaceous, lilac or purple tints), C. incrustata can be distinguished by the basidiomata with very rare clamp connections and ferruginous brown, incrusted hyphae (Wartchow 2012); C. amethystina (Bull.) Donk by the ovoid-ellipsoid or subglobose, slightly larger basidiospores (7‒11 (–12) × 6‒8 μm), while C. amethystinoides (Peck) Corner by the subglobose to broadly ellipsoid (7‒10 × 6‒8 μm). In all phylogenetic analyses, C. ossea comes an isolated position within the genus.

 

Phylogenetic tree of the Clavulina obtained by analyses from rDNA sequences. Taxa with two accession numbers were analysed by concatenated ITS and partial LSU rDNA; both regions ITS and partial LSU rDNA was used to analyse the other individuals. Support values (from top) are maximum likelihood, maximum parsimony and Bayesian analyses. Sequences obtained in this study are in boldface. Only support values of at least 50% are shown. The tree was rooted with Hydnum albomagnum, H. repandum and H. umbilicatum.

 

Clavulina ossea (URM 89970, holotype). a, b Basidiomata. c, d Incrusted hyphae with clamps (Melzer, KOH+floxine, respectively). e basidiospores (KOH+floxine, KOH, Melzer’s, respectively). Scale bars: a = 1 cm, b = 2 cm, c-e = 10 µm.