Cyphellophoriella pruni Crous & A.J. Sm., Sydowia 67: 96 (2015)

Index Fungorum number: IF812525; MycoBank number: MB812525

Mycelium consisting of smooth, pale brown, septate, branched, 2–3 µm diam. hyphae. Conidiogenous bodies separate to aggregated. Initially a globose mother cell, 3–4 µm diam. forms on hyphae, giving rise to 4–14 globose to ampulliform, pale brown, smooth conidiogenous cells in a flower arrangement (like petals), 3–6 × 2–4 µm; conidiogenous cells tapering from globose base to thin apex, 1 µm diam., phialidic with minute periclinal thickening, but collarette not visible; outside of conidiogenous cells forming a tube that encloses the conidiogenous cells, brown, verruculose, varying from subcylindrical to ampulliform, 10–20 × 8–13 µm; apex opening and exuding a slimy conidial mass. Conidia solitary, hyaline to pale brown, smooth, spindle-shaped, curved, apex obtuse, base truncate, (13)15–18(22) × 1(1.5) µm.

Culture characteristics – Colonies spreading, lacking aerial mycelium, with smooth, lobed margins, reaching 20 mm diam. after 1 month at 25 ºC. On PDA surface and reverse olivaceous black; on OA surface olivaceous black; on MEA surface olivaceous grey, reverse iron grey.

Material examined – USA, California, Berkeley, on an apparently healthy leaf of a Prunus sp. (Rosaceae), 26 March 2014, leg. A. J. Smith (holotype CBS H-22255, culture ex-type CPC 25120 = CBS 140001).

Notes – Cyphellophoriella resembles the genus Cyphellophora (Chaetothyriaceae, Chaetothyriales, Eurotiomycetes), which is characterised by having phialides formed directly on hyphae (or with reduced conidiophores and collerettes), giving rise to multiseptate, curved conidia (Crous et al. 2007, 2009a, 2013b). Cyphellophoriella is primarily distinguished by its unique flower-like arrangement of conidiogenous cells, attached to a mother cell. Cyphellophoriella is alsio similar to Polystratorictus (P. fusarioides, from palm leaf litter, Peru; Matsushima 1993), but distinct because the latter species has conidiophores that appear better differentiated on the mother cell, the rosette of conidiogenous cells are not surrounded with a collarette, and the conidia are broad and septate. Based on the ITS phylogeny, Cyphellophora and Cyphel­lophoriella are not congeneric and Cyphellophoriella pruni has Ceramothyrium carniolicum (GenBank KC978733) as closest sister.