Guttulispora crataegi
Guttulispora crataegi Qing Tian, Thambug., Camporesi & K.D. Hyde, in Thambugala et al., Fungal Diversity: 10.1007/s13225-015-0348-3, [22] (2015)
Index Fungorum number: IF 551239; Facesofungi number: FoF 00805
Etymology: Referring to the host genus Crataegus.
Holotype: MFLU 14-0584
Saprobic on a dead and branches of Crataegus sp. Sexual morph: Ascomata 175.5–363 × 152.5–313.5 μm diam. (x̄ =288.5 × 226 μm, n = 10), solitary or scattered, immersed, coriaceous to carbonaceous, dark brown to black, globose to subglobose, ostiolate. Ostiole central, papillate, with a small crest-like apex and an irregular pore-like opening, plugged by gelatinous tissue, made up of lightly pigmented, pseudoparenchymatous cells. Peridium 28–46.5 μm wide (x̄ = 38 μm, n = 12), composed of a single stratum, with dark to reddish brown, thick-walled cells of textura angularis, cells towards the inside lighter, at the outside, darker, somewhat compressed, fusing and indistinguishable from the host tissues. Hamathecium comprising 1–2 μm wide, septate, branched, cellular pseudoparaphyses, situated between and above the asci, embedded in a gelatinous matrix. Asci 45–130 × 7.5–11 μm (x̄ = 83 × 9.5 μm, n = 10), 8-spored, bitunicate, fissitunicate, cylindrical, short-pedicellate, apically rounded with an ocular chamber. Ascospores 14.5–18.5 × 5.5–7 μm (x̄ = 16 × 6 μm, n = 10), uniseriate, partially overlapping, hyaline when immature and becoming brown when mature, ellipsoid to fusiform, 3-septate, constricted at the each septa, upper part slightly wider, guttulate at each cell, smooth-walled, lacking a mucilaginous sheath. Asexual morph: Undetermined.
Culture characteristics: Ascospores germinating on PDA within 18 h and producing germ tubes from several septa. Colonies on PDA reaching 20 mm diam. after 4 weeks at 25 °C, effuse to raised, surface grey, reverse greenish-black, dense, with entire to slightly undulate, greyish green edge, producing a yellowish pigment in the culture.
Material examined: ITALY, Province of Forlì-Cesena [FC], Marsignano - Predappio, on dead branch of Crataegus sp. (Rosaceae), 15 March 2013, Erio Camporesi IT 232 (MFLU 14–0584, holotype); ibid., (HHUF 30457, isotype), ex-type living culture, MFLUCC 13-0442, ICMP; ibid., 14 May 2013, Erio Camporesi IT 232-2 (MFLU 14-0585, paratype), living culture, MFLUCC 14-0993, ICMP. ibid., 15 April 2013, Erio Camporesi IT 232-3, IT 232-4, IT 232-5 (MFLU 15-1124, 15- 1125, 15-1126, paratypes).
GenBank:
Notes: Guttulispora crataegi is distinct from other species in Lophiostomataceae in having small, brown, guttulate, 3-septate ascospores, constricted at each septa. In the phylogenetic analysis two strains of G. crataegi (MFLUCC 13-0442 and MFLUCC 14-0993), including the ex-type strain, formed a sister group to the new genus Capulatispora which is characterized by coriaceous, conical ascomata surrounded by a small blackened pseudoclypeus, a 4–8 layered, light brown peridium and hyaline ascospores, surrounded by a narrow mucilaginous sheath. Therefore, a new genus Guttulispora is introduced here to accommodate G. crataegi.
Figure x. Guttulispora crataegi (holotype). a–c. Appearance of ascomata on the host surface d. Section through ascoma (note the small crest-like apex) e. Ostiole. f. Section through peridium g. Squash mount of numerous, crowded asci h. Pseudoparaphyses i. Immature ascus j, k. Mature asci l. Apex of ascus with an ocular chamber m. Germinating ascospore n, o. Immature hyaline ascospores p, q. Mature brown ascospores r. Colony on PDA from above. Scale bars: b=1000μm, c= 100 μm, d, g=50 μm, e, f=20 μm, i–l=5 μm, h, m–p=10 μm.
References:
Thambugala KM, Hyde KD, Tanaka K, Tian Q et al. 2015 – Towards a natural classification and backbone tree for Lophiostomataceae, Floricolaceae, and Amorosiaceae fam. nov. Fungal Diversity. 74, 199–266.