Pleosporales » Phaeosphaeriaceae » Loratospora

Loratospora arezzoensis

Loratospora arezzoensis Bundhun, Wanas., R. Jeewon & K.D. Hyde, in Hyde et al., Fungal Diversity 100: 97 (2020)

Index Fungorum number: IF556992; Facesofungi number: FoF 06979

Etymology: The specific epithet “arezzoensis” refers to the name of the Province (Arezzo) from where the fungus was collected.

Holotype: MFLU 171942

Saprobic on dead land stem of rush (Juncus sp.). Sexual morph: Ascomata 109–119 µm high, 104–123 µm diam. (x̄ = 114.4 × 116.3 µm, n = 7), solitary, scattered to aggregated, immersed to erumpent through host surface, noticeable as small black spots on host surface, uni- to bi-loculate, globose to subglobose, dark brown to black, glabrous, centrally ostiolate. Ostiole up to 27 µm and 31 µm wide, central, minutely papillate, dark brown, composed of light brown periphyses. Peridium of unequal thickness, thicker at the apex (19–25 µm) and thinner at the sides and base (11–16 µm), composed of 5–7 layers of thick-walled, dark brown to black pseudoparenchymatous cells of textura angularis to textura globulosa. Hamathecium composed of sparse, filamentous, indistinct, septate pseudoparaphyses, anastomosed above the asci, embebbed in mucilaginous matrix. Asci 66–75(–83) × 14–19 µm (x̄ = 71.4 × 16.3 µm, n = 11), 8-spored, bitunicate, fissitunicate, cylindric-clavate, sessile to short pedicellate; apex rounded, thick-walled, with well-developed ocular chamber. Ascospores 32–37 × 4–5 µm (x̄ = 34.5 × 4.3 µm, n = 20), overlapping or parallel, 3–5-seriate, phragmosporous, narrowly elongate fusiform with rounded ends, slightly curved, 3-transversely septate, faintly constricted at the central septum, initially hyaline, becoming pale yellow at maturity, rough-walled, surrounded by a thick, distinct sheath. Asexual morph: Undetermined.

Material examined: ITALY, Province of Arezzo, near Eremo di Camaldoli, on dead aerial stem of Juncus sp., 2 October 2017, E. Camporesi, IT 775 (MFLU 171942, holotype).            

GenBank Numbers: ITS: MN756638; LSU: MN756636; SSU: MN756634.

Note: Loratospora arezzoensis shares similar characteristics with the type species, L. aestuarii in its ostiole comprising brown periphyses, peridium made up of cells of textura angularis to textura globulosa and shape of the asci and ascospores. It also occurs on Juncus sp. similar to L. aestuarii. However, L. arezzoensis difers from L. aestuarii in its smaller ascomata (109–119 µm high, 104–123 µm diam. versus 130–250  μm high, 160–310  μm diam., Phookamsak et al. 2014). Its asci are smaller and cylindric-clavate (x̄ = 71.4 × 16.3 µm versus x̄ = 80.9 × 28.2 μm; Phookamsak et al. 2014) as compared to the ovoid or ampulliform asci of L. aestuarii. The ocular chambers for the asci of L. arezzoensis are conspicuous as compared to the asci of L. aestuarii which have indistinct ocular chambers. The ascospores of L. arezzoensis are also smaller than L. aestuarii (x̄ = 34.5 × 4.3 µm versus x̄ = 46.7 × 6.7 μm; Phookamsak et al. 2014) with a slight constriction at the central septum and a thick surrounding mucilaginous sheath. Furthermore, while L. aestuarii occurs in a marine environment (Kohlmeyer and Volkmann-Kohlmeyer 1993, Monkai et al. 2013), L. arezzoensis occurs on dead terrestrial hosts.