Xylariales » Xylariales genera incertae sedis » Pyriformiascoma

Pyriformiascoma trilobatum

Pyriformiascoma trilobatum Daranag., Camporesi & K.D. Hyde, in Daranagama, Camporesi, Tian, Liu, Chamyuang, Stadler & Hyde, Fungal Diversity 73: 230 (2015)

Index Fungorum number: IF 809527; Facesofungi number: FoF 00329

Etymology: In reference to the characteristic tri-lobed apical apparatus.

Saprobic on wood, stems and twigs. Sexual morph: Ascomata immersed, mostly solitary, appearing as blackened, slightly raised, conical areas, with central black ostiolar dot, in cross section 250–300 × 300 μm (x̄ = 269.5 × 300 μm, n=10), obpyriform, with ostiolar canal comprising broadly rounded host cells, 20–30 × 20–25 μm (x̄ = 23.8 × 21.5 μm, n=10). Peridium 15–20 μm diam. (x̄ = 15.5 μm, n=10), with few cell layers, outwardly comprising dark brown cells of textura oblita and inwardly comprising hyaline cells of textura angularis. Paraphyses 2.5 μm diam. (x̄ = 2.5 μm, n=10), numerous, filamentous, septate. Asci 70–85 × 4.5–6 μm (x̄ = 82 × 5.5μm, n=30), 8-spored, unitunicate, cylindrical, short-pedicellate, apically rounded, with cytoplasm forming fork-like invagination below indistinct apical apparatus, J-, apical apparatus, 5–7 × 3–4 μm (x̄ = 5.7 × 3.5 μm, n = 30). Ascospores 15–18 × 4.5–6 μm (x̄ = 16.5 × 5.5 μm, n=40), overlapping uniseriate, inequilaterally oblong-ellipsoidal, dark brown, unicellular with a hyaline dwarf cell at base, 2–2.5 μm in length (x̄ = 2.2 μm, n=40), smooth-walled, larger cell olivaceous-green, lacking a germ slit. Asexual morph: Conidiophores up to 65–90 × 3.6–6 μm (x̄ = 87.5 × 5 μm, n=20), simple, pale brown, rarely branched, aseptate. Conidiogenous cells 18–22 × 6.2–6.5μm (x̄ = 19.5 × 6.4 μm, n=20), terminal, single, cylindrical, denticals present, if not smoothly curved. Conidia 13.5–17 μm in diam. (x̄ = 15.3 μm, n=20), light brown, globose, smooth.

Culture characteristics: Colonies on Difco OA plates at 25–27 °C reaching 9 cm edge of Petri-dish in 1 month, at first Citrine (13), felty, azonate, with diffuse margins, after 2 weeks become yellowish brown and isebelline and zonate; reverse turning yellow and dark brown, zonate, two types of mycelium present, thin mycelium and thick mycelium. Conidiophores emerge from the thick mycelium, which formed into hyphal aggregates that are melanised and thickened, usually light brown.

Material examined: ITALY, Province of Forlì-Cesena, Monte Riccio-Bagno di Romagna, on Cornus sp. (Cornaceae), 18 October 2013, E. Camporesi IT1483 (MFLU 14-0231, holotype), ex-type cultures, MFLUCC 14-0012=ICMP; Ibid, 18 October 2013, E. Camporesi IT1483 (PDD, isotype).

GenBan: ITS–KP297402, RPB2–KP340530, ß-tubulin– KP406613, LSU–KP340543

Notes: Pyriformiascoma trilobatum share characters with several Anthostomella species, such as, A. clypeata (De Not.) Sacc., A. rostrospora W.H. Hsieh et al. and A. nypicola K.D. Hyde et al., which have unicellular ascospores with a hyaline dwarf cell and a dark large cell, and lack a sheath or germ slit. Anthostomella clypeata differs from Pyriformiascoma trilobatum as it has a well-developed clypeus and globose ascomata, a peridium comprising elongate, angular cell layers, both inwardly and outwardly and asci with a J+, wedged-shaped, apical apparatus. Anthostomella rotrospora has globose asomata and asci with a wedged-shape, J+, apical apparatus and ascospores with a hyaline larger cell with an acute end at the upper part. The same olivaceous larger cell is present in A. nypicola, however it is different from the new taxon as A. nypicola has globose to subglobse ascomata with thick-walled layers,with compressed cells, and asci with a J+, wedged-shaped, apical apparatus. Three Anthostomella species discussed in Lu and Hyde (2000) have a uniseriate ascospore arrangement, while in Pyriformiascoma trilobatum the arrangement is biseriate. A comparison of morphological characters of the genera examined in this study is provided below.