Kalmusia ebuli Niessl, Verh. nat. Ver. Brünn 10: 204 (1872) (Fig 7)

Index Fungorum number: IF 594929; MycoBank number: MB 171554; Facesoffungi number: FoF 00041

Saprobic on dead stems. Sexual state: Ascomata 290–360 × 300–520 μm (= 300 × 430 µm, n = 10), solitary, scattered, or in small groups, immersed to erumpent, globose or subglobose, coriaceous, wall black, with or without papilla, ostiolate. Papilla small, with small ostioles. Peridium 15– 40 μm wide, comprising one cell type of small, pigmented, dark brown to black, thick-walled cells of textura prismatica to textura angularis. Hamathecium of dense, 1.5 μm wide, delicate pseudoparaphyses, 1–septate, branching and anastomosing between and above asci, embedded in mucilage. Asci 75–125 × 10–15 μm (= 90 × 12 μm, n = 10), 8-spored, bitunicate, fissitunicate, clavate, with a long, narrow, furcate pedicel up to 45 μm long, and a shallow ocular chamber. Ascospores 15–18 × 5–7 μm (= 16 × 6 μm, n = 10), biseriate, narrowly ovoid to clavate, pale brown, 3-distoseptate, without constriction, smooth-walled. Asexual state: unknown.

Material examined – MORAVIA, Bruno, on dead stems. (LUX 045054, isotype)

Fig. 1 Kalmusia ebuli (LUX 045054, isotype). a Hebarium packet. b-c Surface view of ascomata on host substrate (bark). d Longitudinal section ascoma with clypeus. e Close-up of the peridium. f Broad, septate pseudoparaphyses. g Long, narrow asci with furcate pedicel. h–i Pale brown ascospores with 3-distosepta. Scale bars: d = 80 µm, e = 10 µm, f = 5 µm, g =25 µm, h–i=15 µm.

Notes – Kalmusia was characterized as “immersed, sphaeroid ascoma with central, stout papilla, surrounded by hyphae in the substrate, stipitate asci with septate pseudoparaphyses, and brown, 3-septate, inequilateral ascospores” by Barr (1992). The most morphologically comparable genus to Kalmusia is Thyridaria, which had been treated as a subgenus under Kalmusia (Lindau 1897) and was subsequently transferred to Platystomaceae in Melanommatales (Barr 1987, 1990). After comparing their morphological characters, Diapleella and Dendropleella were also considered synonyms of Kalmusia.

Compared to Thyridaria, Kalmusia has sphaeroid ascomata, a peridium of small pseudoparenchymatous cells, basal asci and very thin pseudoparaphyses, thus it was assigned to Phaeosphaeriaceae by Barr (1990), and the genus is utilized to accommodate K. ebuli and K. clivensis (Berk. & Broome) M.E. Barr, as well as closely related species, i.e. K. utahensis (Ellis and Everh.) Huhndorf & M.E. Barr and K. coniothyrium (Fuckel) Huhndorf (Barr 1992). But this proposal is questionable because the clavate asymmetric ascospores as well as the clavate asci with long pedicels of K. ebuli do not fit the concept of the Phaeosphaeriaceae as defined by Zhang et al. (2012) and are excluded from the family by Phookamsak et al. (2014)

Most recent phylogenetic studies indicated that some species of Kalmusia reside outside of the family Phaeosphaeriaceae (Zhang et al. 2009). Kalmusia ebuli, the type species of Kalmusia, lacks type material and as such its phylogenetic position has remained unresolved. As a consequence, the familial position of Kalmusia is based on morphology and molecular phylogeny of species other than the type (Zhang et al. 2014). Recently, a fresh collection of K. ebuli was obtained from decorticated wood of Populus tremula in the foothills of the French Pyrenees (Zhang et al. 2014). The new collection was designated as a neotype to stabilize the application of the species and genus name. Zhang et al. (2014) also observed the holotype of K. ebuli f. sarothamni, and it was found to be a synonym of K. ebuli. They concluded that the genus Kalmusia is polyphyletic within the family Montagnulaceae, with K. ebuli distantly placed from K. brevispora and K. scabrispora, which appear to represent a different genus. During our phylogenetic analysis, we also obtained similar results, with K. ebuli being distantly placed from K. brevispora and K. scabrispora and forming a distinct clade sister to a newly introduced asexual genus Alloconiothyrium in Didymosphaeriaceae. Furthermore, a recently introduced asexual genus, Dendrothyrium (typified with D. variisporum (CBS 121517T) and another species of Dendrothyrium, D. longisporum (CBS 582.83T), clustered within the Kalmusia ebuli clade. Therefore, we propose to synonymize Dendrothyrium under Kalmusia by giving priority to the older name and combining two species under Kalmusia.