Phragmoporthe conformis

Phragmoporthe conformis (Berk. & Broome) Petr., Annls mycol. 39(4/6): 285 (1941)          

Basionym – Sphaeria conformis Berk. & Broome, Ann. Mag. nat. Hist., Ser. 2 9: 325 (1852)

For synonyms see Index Fungorum (2020)         

Index Fungorum number: 289480; Facesofungi number: FoF 01794                              

Saprobic on Alnus glutinosa L. Sexual morph: Appearing as conical, pustules on the host surface. Ascomata perithecial, minutely stromatic, immersed, erumpent. Perithecia 700–770 μm diam. (n=20), solitary, immersed in or directly below the host epidermis, globose, membranous, dark brown to black, with a periphysate ostiole. Peridium 14–38 μm (x̄ = 22 μm, n =10) wide, comprising 7–15 cell layers, outer layers heavily pigmented, thin-walled, comprising dark brown cells of textura angularis, inner layers composed of hyaline to brown, thin-walled, flat cells of textura angularis. Hamathecium lacking paraphyses. Asci 60–80 × 17–24 μm (x̄ = 72 × 19.5 μm, n =30), 8-spored, unitunicate, clavate, straight, short pedicellate, apically rounded or truncate, with a refractive, J- apical ring. Ascospores 19–24 × 6.5–8 μm (x̄ = 22 × 7 μm, n =50), multi-seriate, fusiform, mainly with 3 transverse septa, occasionally constricted at septum, hyaline, smooth and thick-walled, without a mucilaginous sheath or appendages. Asexual morph: Undetermined.

Material examined: ITALY, Forlì-Cesena Province, Lago Pontini-Bagno di Romagna, dead branches of Alnus glutinosa (L.) Gaertn. (Betulaceae), 26 May 2014, Erio Camporesi, IT1892 (MFLU 15–2662 reference specimen designated here), also in HKAS 92498, living culture, MFLUCC 14–0567.

GenBank Numbers: ITS: KU315388; LSU: KU315389; SSU: KU315390; tef1-α: KU315391

Note: Berkeley and Broome (1852) originally described Phragmoporthe conformis as Sphaeria conformis on Alnus spp. from the UK. Later Petrak (1941) synonymized Sphaeria conformis under Phragmoporthe conformis. The ascomata, asci and ascospores sizes of our strain are typical to P. conformis (Petrak 1941) and the molecular data is identical to CBS 109793. Therefore MFLUCC 14–0567 strain can be designated as a reference specimen of P. conformis to stabilize the taxonomy of the genus.