Rossiomyces R.K.Benj., 2001

Santamaria, Sergi & Pedersen, Jan, 2021, Laboulbeniomycetes (Fungi, Ascomycota) of Denmark, European Journal of Taxonomy 781, pp. 1-425 : 245

Genus Rossiomyces R.K.Benj.

MB#28566

Aliso 19: 132 ( Benjamin 2001). –

Type species: R. falcatus (T.Majewski) R.K.Benj. (by monotypy)

Brief description

Monoecious. Receptacle three-celled. Primary appendage free, consisting of three superposed cells, where the median and upper cells give rise to antheridia, with a spinous process on the upper cell ( Fig. 55B , sx). Perithecium with five cells in each vertical row of outer wall cells; showing apical conspicuous prominences.

Remarks

Monotypic. Benjamin (2001) reviewed and narrowed the limits of the genus Autophagomyces , erecting the new genus Rossiomyces based on Autophagomyces falcatus T.Majewski , with a combination of the following seven characteristics: (1) the structure of primary appendage (see brief description above), (2) the spinous process formed by the original spore, (3) cells I and II separated by a strongly oblique septum, (4) cells III and II separated by a strongly oblique septum, the first in contact with cell I, (5) the simple or bifurcate trichogyne, (6) the small remnant of trichogyne, and (7) the five tiered perithecial outer wall. Waiting for the discovery of additional species, it is currently difficult to delimit specific characters from generic ones.

Figures

Fig. 55. A–B. Rossiomyces falcatus (T.Majewski) R.K.Benj. A. Mature thallus. B. Immature thallus showing labelled cells I, II, III, primary septum (a), trichogyne (tr), and spinous process from the original spore apex (sx). – C–D. Sphaleromyces lathrobii Thaxt. C. Mature thallus showing protrusion of cell III (arrow). D. Mature thallus from Spain showing labelled cells I, II and III. – E–G. Stichomyces conosomatis Thaxt. Mature thalli. Scale bars: 50 µm. Photographs from slides ZMUC C-F-122733 (A–B), ZMUC C-F-124186 (C), BCB-SS1543a (D), ZMUC C-F-122729 (E, G), ZMUC C-F-122630 (F).