Diaporthales » Sydowiellaceae » Sillia

Sillia italica

Sillia italica N.I. de Silva, Camporesi & K.D. Hyde, in Tibpromma et al., Fungal Diversity 83: 117 (2017)

Index Fungorum number: IF 552716; Facesofungi number: FoF 2801

Etymology: Referring to the country where the fungus was first collected.

Holotype: MFLU 16-0056

Saprobic on a dead branch of Corylus sp. (Corylaceae). Sexual morph: Stroma erumpent from cracks, up to 1–2.5 mm in diam., black on the surface. Ascomata 480–745 μm high × 136–346 μm diam. (x̄ = 640 × 242 μm, n = 10), semi-immersed in black stromatic tissues gregarious, globose to subglobose, ostiolate, soft and found in a valsoid arrangement. In 10% KOH solution stroma becomes brownish-red. Ostioles 330–570 μm long, cylindrical, forming at the center of the ascomata, raised from the host surface. Peridium 20–34 μm thick, with outer layer of brown and thick-walled cells of textura prismatica; inner layer of hyaline and thin-walled cells of textura angularis. Paraphyses 4–7 μm wide, cylindrical, cellular, septate, mixed with asci. Asci 147–234 × 10–15 μm (x̄ = 190 × 13 μm, n = 25), 8-spored, unitunicate, narrowly clavate, straight or somewhat curved, with a short obtuse pedicel. Ascospores 99–128 × 3.1–4.6 μm (x̄ = 109 × 3 μm, n = 30), fasciculate, hyaline, filiform, elongate, narrow and curved at the ends, guttulate, smooth-walled, with 3 transverse septa. Asexual morph:  Undetermined.

Material examined: ITALY, Forlı`-Cesena Province, Monte Mirabello–Predappio, on a dead twig of Corylus sp. (Corylaceae), 11 January 2016, Erio Camporesi, IT2754 (MFLU 16-0056 holotype, BBH isotype).

GenBank: LSU: KY397949; ITS: KY523484.

Notes: Sillia italica strains analyzed herein are sister taxa to S. ferruginea, S. karstenii and this relationship is well-supported (Tibpromma et al. 2017). This close phylogenetic affinity is also supported by morphological similarities. Both S. ferruginea and S. italica become reddish in 10% KOH solution (Iznova and Rukseniene 2012). Sillia italica however, has some distinct characters as compared to S. ferruginea. Stromatic tissues of S. ferruginea comprise black tissues on the surface and inner yellow stromatic tissues mixed with black tissues (Iznova and Rukseniene 2012), while S. italica contains black stromatic tissues. The ascomata arrangement of S. italica is valsoid, whereas in S. ferruginea it is diatrypoid. Sillia italica has clavate asci similar to S. ferruginea, but they are longer (147–234 μm vs. 96–115 μm). Ascospores of S. italica are 99–128 μm long with 3 septa, while in S. ferruginea they are 65–72 μm long with 3–5 septa. Senanayake et al. (2017) introduced Sillia karstenii which morphologically differs from S. italica in having large ascomata with very poorly developed stromata. The phylogenetic analysis of Senanayake et al. (2017) also showed that S. italica is phylogenetically distinct from other Sillia species (Tibpromma et al. 2017).