Hermatomyces Speg., Anal. Mus. nac. B. Aires, ser. 3 13: 445 (1911).
Index Fungorum number: IF 8517; Facesoffungi number: FoF 08252, 27 morphological species (Species Fungorum 2021), 24 species with molecular data.
Saprobic on host. Asexual morph: Colonies on the natural substrate forming sporodochial conidiomata, superficial, scattered, more or less circular or oval, mostly non-subiculate, gray-black, consisting of an orbicular, blackish gray, flattened outer zone sometimes with a poorly developed subiculum and a black, glistening, granulose sporulating centre. Mycelium mostly superficial, composed of a loose or compact network of repent, branched, septate, smooth, locally thick-walled, pale brown to brown hyphae. Subicular hyphae short, ascending, irregularly geniculate or flexuous, densely packed, anastomosing. Conidiophores micronematous or semi macronematous, mononematous, cylindrical, erect, subhyaline or pale brown. smooth or finely verruculose, often corresponding to conidiogenous cells. Conidiogenous cells monoblastic, integrated, terminal, determinate, subhyaline to pale brown or brown, cylindrical or slightly subulate, often arising directly on the superficial mycelium and closely packed together at the fertile centre, sphaerical, subsphaerical or ampulliform. Conidia of two types, solitary, fry; lenticular conidia muriform, smooth, broadly ellipsoidal in front view, central cells brown or dark brown to blackish brown, peripheral cells sub hyaline to pale brown, forming a wide and distinct ring, ellipsoidal to narrowly oblong or oblong in side view where two distinct adpressed halves can be recognized, each half seen laterally as a row of 4–7 cells, end cells subhyaline to pale brown, middle cells dark brown or blackish brown; cylindrical conidia bifurcated, straight or flexuous, septate, constricted at the seta, consisting of two columns of 3 cells, very rarely 2-celled, basal cells bulbous, globose or subglobose, smooth, hyaline, tightly appressed together, middle and apical cells diverging, doliiform, cylindrical or subcylindrical, apical cells clavate or doliiform, verrucose, subhyaline or pale brown, apex rounded and dark brown or blackish brown. Sexual morph: Unknown (Adapted from Speggazini 1911).
Type species: Hermatomyces tucumanensis Speg.
Notes: Hermatomyces was introduced by Spegazzini (1911) with H. tucumanensis as type species. Spegazzini (1911) recognized only one type of conidia, the nearly globose parenchymatic lenticular conidia, and interpreted the cylindrical ones as conidiophores. Hughes (1953) introduced the combination H. sphaericus for a hermatomyces-like taxa initially described as Stemphylium sphaericum with only lenticular conidia. Hermatomyces was introduced based only on the hyphomycetous asexual morph, and it has been treated as ‘incertae sedis’ for several years (Wijayawardene 2012). Hermatomyces was transferred to Lophiotremataceae based on multigene phylogenetic analyses using SSU, LSU, TEF1-α, and RPB2 gene regions (Tibpromma et al. 2016a; Doilom et al. 2017). Hashimoto et al. (2017) found that Hermatomyces is distantly related to Lophiotremataceae by including several taxa of Lophiotremataceae, and Hermatomyces was placed in Hermatomycetaceae. Currently, Hermatomyces is a distinct genus in Hermatomycetaceae.