Heterosphaeria umbilicata (Pers.) W.J. Li & K.D. Hyde, comb. nov.
≡ Peziza umbilicata Pers., Mycol. eur.1: 323 (1822)
= Heteropatella umbilicata (Pers.) Grove, J. Bot., Lond. 56: 319 (1918)
Index Fungorum number: IF557168, Facesoffungi number: FoF 07421
Saprobic on dead stems of herbaceous plant forming conspicuous, rounded to oval, erumpent, black, fruiting bodies. Sexual morph: undetermined. Asexual morph: Conidiomata 100–500 µm diam., 70–400 µm high, pycnidial, globose to subglobose, semi-immersed to superficial, separate to gregarious or confluent, unilocular, glabrous, thick-walled, ostiolate. Ostiole 60–130 µm long, 50–120 µm wide, cylindrical, single, centrally or excentricity located. Conidiomata 20–90 µm wide, composed of outer several layers of textura globosa to textura angularis, with thick-walled, dark brown cells, and inner layers of textura angularis, with thick-walled, hyaline cells. Conidiophores hyaline, branched, septate, formed from the innermost layer of wall cells. Conidiogenous cells 9–30 × 1–4 µm, hyaline, enteroblastic, cylindrical to subcylindrical, denticulate, integrated to occasionally discrete, smooth-walled, with a slightly wider apex, proliferating sympodially 2–3 times. Conidia 22–46 × 2–4 µm ( = 34 × 3 µm; n = 50), hyaline, long-fusiform to naviculate, 1–3-septate, slightly constricted at septa, guttulate, smooth-walled, bearing appendages, basal cell 4–12 µm long ( = 7 µm), obconic with a truncate or rounded base, median cells mostly 2, occasionally 1, together 13–20 µm long ( = 14 µm), cylindrical to doliiform, apical cell narrow conical and attenuated into an unbranched, cellular appendage, with a total length 8–22 µm ( = 14 µm), basal appendage often lacking, but when present, tubular, unbranched, attenuated, 1–3.8 µm long ( = 2.6 µm).
Material examined: Italy, Province of Trento, Vermiglio, near Passo del Tonale, on dead aerial stems of Plantago sp. (Plantaginaceae), 28 June 2012, Erio Camporesi, IT507 (MFLU 19-2874, reference specimen); ibid., Province of Trento, Mezzana, Marilleva, on dead aerial stems of Heracleum sphondylium (Apiaceae), 9 August 2012, Erio Camporesi, IT656 (MFLU 19-2875), (KUN, HKAS93657); ibid., Province of Forlì-Cesena, Predappio Alta, on dead aerial stems of Torilis arvensis (Apiaceae), 22 September 2012, Erio Camporesi, IT742 (MFLU 19-2878), (KUN, HKAS93661).
Notes: Three specimens (MFLU 19-2874/IT507, MFLU 19-2875/IT656 and MFLU 19-2878/IT742) were collected from Italy on dead stems of Plantago sp., Heracleum sphondylium and Torilis arvensis, respectively. These collections have similar form of conidiomata, conidiogenous cells and conidia as well as conidial dimensions, MFLU 19-2874/IT507 (22–39 × 2–3 µm ( = 32 × 2.4 µm; n = 50), MFLU 19-2875/IT656 (22–41 × 2.6–4 µm ( = 34 × 3 µm; n = 50), MFLU 19-2878/IT742 (23–46 × 2.5–4 µm ( = 35 × 3.4 µm; n = 50). The descriptions of these collections match the concept of H. umbilicata, and the only distinguishing character is their conidial dimensions. However, it should be noted that this character may not be very reliable, for example, Nag Raj (1993) gave conidia dimensions for H. umbilicata of 33–49(–59) × 2–3 ( = 41.8 × 2.6 µm), while Sutton (1980) gave 17–22 × 2–2.5 µm. Based on morphological information, these collections are regarded as conspecific with H. umbilicata.
These specimens were difficult to culture; the sequence of collection MFLU 19-2874/IT507 was obtained by direct sequencing, but we were unable to obtain sequence data for IT656 and MFLU 19-2878/IT742. Hetersphaeria umbilicata was originally collected from Europe and is associated with various herbaceous plants, e.g., Angelica sylvestris (Apiaceae), Campanula uniflora (Campanulaceae) and Oxyria digyna (Polygonaceae). Because the type specimen lacks sequence data, we designate our collection as a reference specimen.
Heterosphaeria umbilicata (MFLU 19-2874, reference specimen, a, c, d, i, k, p, w–z from MFLU 19-2874/IT507, e, j, o, t–v from MFLU 19-2875/IT656, b, f–h, 1–n, q–s from MFLU 19-2878/IT742) a, b Herbarium specimen. c–e Appearance of dark brown to black conidiomata on the host. f Ostiole. g Section of peridium. h–k Vertical sections of conidiomata. l–p Conidiophores, conidiogenous cells and developing conidia. q–z Conidia. Scale bars b = 500 µm, c–d = 100 µm, e = 200 µm, h–i, k = 100 µm, f, g = 20 µm, j = 50 µm, l–z = 10 µm.
Li WJ, McKenZie EHC, Liu JK, Bhat DJ, Dai DQ, Caporesi E, Tian Q, Maharachcikumbura SSN, Luo ZL, Shang QJ, Zhang JF, Tangthirasunun N, Karunarathna SC, Xu JC, Hyde KD (2020) Taxonomy and phylogeny of hyaline-spored coelomycetes. Fungal Diversity 100: pages279–801.