Paraconiothyrium magnoliae Monkai, Ariyawansa & K.D. Hyde, in Ariyawansa, Tanaka, Thambugala, Phookamsak, Tian & Campo, Fungal Diversity 68: 96 (2014)

Index Fungorum number: IF 550703; MycoBank number: MB 550703; Facesoffungi number: FoF 00056

Etymology: The specific epithet magnoliae is based on the host genus from which the fungus was isolated.

Saprobic on dead leaves in terrestrial environments. Sexual state: Ascomata 130–200 × 150–250 µm (x̅ = 150 × 320 µm, n = 10) small to medium-sized, immersed to semi-immersed, depressed globose, ostiolate. Ostiole papillate, black, smooth, with beak, ostiolar canal lined without hyaline periphyses. Peridium 10–17 μm (= 14 µm, n = 20) wide, usually with 3-5 layers, composed cells of textura prismatica. Hamathecium of dense 2–4 μm (x̅ = 2 µm, n = 20) wide, cellular, septate, hyaline, pseudoparaphyses. Asci 16–27 × 4–6 µm (x̅ = 23 × 5 µm, n = 30), 8-spored, bitunicate, fissitunicate, cylindrical with a short, broad pedicel with a minute ocular chamber. Ascospores 15–30 × 4–7 μm (= 24 × 5, n = 40), uniseriate or partially overlapping, broadly elliptical, yellowish-brown, 3-septate (rarely 4-septate), with small guttules, with bipolar appendage at the tip and one polar appendage on the base, surrounded by a gelatinous sheath. Asexual state: unknown.

Material examined – Thailand, Chiang Mai, Doi Suthep-pui, on dead leaves of Magnoliae liliifera (Magnoliaeceae) 18 September 2011, J. Monkai (MFLU 14-0306, holotype), ex-type living culture MFLUCC 10-0278

NotesParaconiothyrium magnoliae resembles many species of Phaeosphaeria in having 3-septate ascospores with a gelatinous sheath. Phaeosphaeria eustoma and Phaeosphaeria parvula have ascospores which are very similar in size to the morphology of P. magnoliaee. In addition, Parac. magnoliae is similar to Phaeosphaeriatypharum and Phaeosphaeriabarriae in having gelatinous sheathed ascospores (with appendaged ascospores only in Phaeosphaeriabarriae) but differ in the shape of the ascospores. The phylogenetic analysis of combined ITS, LSU, SSU nrDNA and TUB sequences provides strong evidence that Parac. magnoliae belongs in Didymosphaeriaceae, where it forms a separate clade along with Parac.fungicola within the clade of Paraconiothyrium with relatively high bootstrap support (Fig 1), thus a new species is proposed.

Fig. 1 Paraconiothyrium magnolia (MFLU 12-1414, holotype). a–b Fungus on host substrate. c Section of an ascoma. d Cellular, hyaline, septate, broad, pseudoparaphyses. e–g Cylindrical asci with a short, broad pedicel. h–j Yellowish-brown ascospores with bipolar appendage. k Germinating ascospores. Scale bars: c = 50 μm, d = 5 μm, e–g = 30 μm, h–j = 5 μm, k = 10 μm.