Homortomycetaceae Thambugala, A.J.L. Phillips & K.D.Hyde, fam. nov. Index Fungorum Number: IF552086
Foliicolous, associated with leaf spots or saprobic on dead twigs or branches. Sexual morph: Ascomata scattered, immersed to partially erumpent, black, globose to subglobose, ostiolate. Peridium comprising few layers of brown to dark brown, thick-walled cells of textura angularis. Hamathecium composed of septate, cellular pseudoparaphyses. Asci 2–6- spored, bitunicate, fissitunicate, cylindrical, apically rounded. Ascospores uni to bi-seriate, fusiform with broadly to narrowly rounded ends, yellowish brown to brown, 3-septate, smooth walled. Asexual morph: Coelomycetous. Conidiomata pycnidial, solitary or gregarious, immersed or slightly erumpent, uniloculate or multi-loculate, globose to subglobose, ostiolate. Conidiomatal wall comprising a few layers, of lightly pigmented to hyaline cells of textura angularis. Paraphyses intermingled among conidiogenous cells, extending above conidia, hyaline, cylindrical, smooth, flexuous, apex obtuse, sparingly septate. Conidiophores reduced to conidiogenous cells or one supporting cell. Conidiogenous cell with supporting cell, hyaline, percurrently proliferating at the tip of the supporting cells. Conidia ellipsoid to subcylindrical, straight to slightly curved, golden brown to dark brown, 3(−4)-euseptate, apex obtuse, base truncate with a visible scar.
Notes: The genus Homortomyces was introduced by Crous et al. (2012) to accommodate H. combreti Crous & M.J. Wingf., which was associated with leaf spots on Combretum erythrophyllum (Burch.) Sond. and placed in Dothideomycetes genera incertae sedis. Wijayawardene et al. (2014a) described another Homortomyces species, H. tamaricis Wijayaw., Camporesi & K.D. Hyde from dead branches of Tamarix gallica. In the present study, we found the sexual morph of H. tamaricis associated with the same host and this is con firmed by the phylogenetic analyses (Fig. 29). Crous et al. (2012) showed Homortomyces to have phylogenetic affinities in Botryosphaeriales. In our preliminary analysis using LSU sequence data, H. combreti and H. tamaricis formed a separate clade in Botryosphaeriales that was distinct from all other families in this order (Fig. 25). Homortomyces is morphologically similar to Stilbospora, which is currently classified in Stilbosporaceae , Diaporthales, Sordariomycetes (Crous et al. 2012; Wijayawardene et al. 2014a; Maharachchikumbura et al. 2016), while Crous et al. (2012) pointed out four genera (Endocoryneum, Hendersoniopsis, Angiopomopsis and Ceratopycnis) that have conidia similar to Homortomyces. However, all these genera have been classified in incertae sedis and lack se quence data. Morphologically, Homortomyces shares some characteristics of Botryosphaeriales such as stromatic conidiomata, that develop within a preformed stroma, with septate, pigmented, thick-walled, diplodia-like conidia, and clavate, bitunicate, fissitunicate asci with a thick endotunica and a well-developed apical chamber (Phillips et al. 2013). Homortomyces can be distinguished from other members of Botryosphaeriales in having uniloculate, thin-walled ascomata and 3-septate, pigmented ascospores. Based on our phylogenetic analyses (Figs. 25 and 29) and its unique morphology, we recognize Homortomyces as a distinct family (Homortomycetaceae), but its phylogenetic placement is uncertain. Therefore, tentatively we place Homortomycetaceae in Dothideomycetes, families incertae sedis, rather than assigning to Botryosphaeriales, until more fresh collections are made and multi-gene phylogenetic analyses carried out.