Clavulina paraincrustata Meiras-Ottoni & Gibertoni

MycoBank number: MB 818102 Facesoffungi number: FoF 2957

Etymology: paraincrustata (Greek + Latin) = similar to Clavulina incrustata, referring to the extracellular incrustations on the hyphae of the context.

Holotype: URM 89969

Basidiomata branched in caespitose clusters, more rarely solitary or in pairs, somewhat fused basally, initially monopodial but branching early, with fleshy consistency, -8 cm, branches occasionally hollow, tips of branches cristate, stipe visible, sterile, when fresh brownish-orange (6C7, 6C8), branches violet brown (11F8), hymenium unilateral, appearing initially above first branching point. Basidiospores globose to subglobose, 6‒8 (L = 7.49) × 5‒7 (W = 6.32) μm, Q = 1.20, smooth, hyaline, with one large oleiferous guttule, thin-walled, with short apiculus (‒1 μm), IKI-. Hyphal system monomitic, tramal hyphae frequently incrusted, parallel, very compact, brownish, 2‒10 μm, not inflated, without clamp connections. Cystidia absent. Basidia elongate-clavate, 31‒48 × 4, 5‒7 μm, hyaline or with granular cytoplasmic contents, with 2 cornute sterigmata, rarely 3, 4‒5 μm, postpartal septa observed on most basidia.

Specimen examined: BRAZIL, Paraíba: Rio Tinto e Mamanguape, Reserva Biológica Guaribas, May 2015, A. Meiras-Ottoni (URM 89969, holotype; isotype in O).

Additional specimen examined: Brazil, Pernambuco: Igarassu, Refúgio Ecológico Charles Darwin, May 2010, F. Wartchow (URM 82947). GenBank numbers ITS:KX811201; LSU:KX811196.

Notes: This species is characterized by the robust and violet brown basidiomata when fresh, brittle when dry, and incrusted hyphae. It is composed of several solitary or in pairs basidiomata, scattered on soil covered by rotten leaves and branches.

Wartchow (2012) described C. incrustata Wartchow, the first species of Clavulina with incrusted hyphae, based in material collected in Brazil. Despite being microscopically similar, it differs from C. paraincrustata by the less robust, paler basidiomata, and the amphigenous hymenium. DNA of the type was tentatively extracted, without success.

Clavulina paraincrustata was grouped (94% ML/94% MP/1.00BYPP) with C. craterelloides and C. rosiramea Uehling, T.W. Henkel & Aime, from which can be distinguished by the lack of incrusted hyphae. Additionally, C. craterelloides has infundibuliform basidiomata, subglobose to broadly ellipsoid basidiospores [(6.5) 7.5–8 × (5.5) 6–7 (7.5) μm], while C. rosiramea has simple or slightly branched basidiomata, with orange tints, subglobose to slightly triangular [(6.5) 7‒9 (10) × (6) 7‒8 (9) μm].

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 paraincrustata (URM 89969, holotype). a Basidiomata. b Incrusted hyphae (KOH). c Basidia (KOH). d Basidiospores (KOH). Scale bars: a = 2.5 cm, b, d = 10 µm, c = 20 µm.