Pleosporales » Didymosphaeriaceae » Pseudocamarosporium

Pseudocamarosporium ulmi-minoris

Pseudocamarosporium ulmi-minoris Wanas., Camporesi, E.B.G. Jones & K.D. Hyde, in Wanasinghe et al., Fungal Diversity: 10.1007/s13225-018-0395-7, [40] (2018)

Index Fungorum number: IF554135; Facesofungi number: FoF 03973

Etymology: The specific epithet reflects the host species Ulmus minor.

Holotype: MFLU 16-2707.

            Saprobic on dead branches of Ulmus minor. Sexual morph: Undetermined. Asexual morph: Conidiomata pycnidial, 200–300 μm high, 220–350 μm diam. (x̄ = 235.5 × 264.1 μm, n = 10), solitary or gregarious, black, immersed, sometimes scattered beneath the host periderm or on decorticated wood, fully or partly erumpent, unilocular, with a papillate ostiolate. Ostiole central, long, smooth, ostiolar canal filled with hyaline or pale brown cells. Pycnidial wall multi-layered, 10–15 μm wide at the base, 15–20 lm wide at the sides, comprising 2 layers, outer layer heavily pigmented, thick-walled, comprising blackish or to dark reddish-brown cells of textura angularis, cells towards the inside lighter, inner layer composed of 1–2 layers, hyaline, thin-walled, cells of textura angularis. Conidiophores reduced to conidiogenous cells. Conidia 14–17 × 6–9 μm (x̄ = 15.5 × 7.1 μm, n = 20), oval, straight to slightly curved, rounded at both ends, with 3 transverse septa, with the 1-longitudinal septum, muriform, smooth-walled, brown to blackish-brown.

Material examined: ITALY, Forli-Cesena Province [FC], Teodorano—Meldola, on dead aerial branches of Ulmus minor Mill. (Ulmaceae), 21 October 2016, Erio Camporesi IT 3134 (MFLU 16-2707, holotype); ex-type living culture, MFLUCC 17-0671.

GenBank Numbers: ITS: MG828951; LSU: MG829062; SSU: MG829167.

Notes: During our investigation on diversity of camarosporium-like fungi in Italy, an isolate was collected from Ulmus minor species in Forli-Cesena Province. Morphological characters such as pycnidial, globose conidiomata, ampulliform conidiogenous cells and brown muriform conidia (Fig. xx), fit well within the species concept of Camarosporium. DNA sequence analyses from the ribosomal and protein genes confirm that our new taxon belongs to Pseudocamarosporium in Didymosphaeriaceae. Our new isolate (MFLUCC 17-0671) shares a close relationship with Pseudocamarosporium lonicerae (MFLUCC 13-0532), P. corni (MFLUCC 13-0541) and P. pteleae (MFLUCC 17-0724). In a comparison of the 446 ITS (+ 5.8S) nucleotides of these four strains reveals >10 (2.42%), the number of differences justifies the establishment of a new taxon (Jeewon and Hyde 2016). Therefore, we propose MFLUCC 17-0671 as a new species in Pseudocamarosporium.