Rhachomyces neoproliferans W.Rossi & M.Leonardi, 2021

Buyck, Bart, Eyssartier, Guillaume, Dima, Bálint, Consiglio, Giovanni, Noordeloos, Machiel Evert, Papp, Viktor, Bera, Ishika, Ghosh, Aniket, Rossi, Walter, Leonardi, Marco & Das, Kanad, 2021, Fungal Biodiversity Profiles 101 - 110, Cryptogamie, Mycologie 20 (5), pp. 63-89 : 64-66

101. Rhachomyces neoproliferans W.Rossi & M.Leonardi , sp. nov.

( Fig. 1)

Rhachomyces proliferans Lepesme , Bulletin du Muséum d’histoire naturelle de Paris, Sér. 2: 598 (1941), nomen invalidum

A B

DIAGNOSIS. — Large thalli with frequently ramified receptacle bearing very many antheridia, relatively few appendages and one or more stalked perithecia.

HOLOTYPE. — Romania. Muntii Apuseni , Valea Lesului, pestera cu Apa, 31.V.1996, J. Prouza, on the legs of D. (B.) paroecus (J. Frivaldszky) (FI WR4491b).

MYCOBANK. — MB 839029.

ETYMOLOGY. — From Latin neo- = new (in compound words), and proliferans , the previous invalid name given to the fungus.

ADDITIONAL EXAMINED MATERIAL. — Romania. Bihor Mts., near Campéni, 600-700 m, 8.V.1981, J. Janák, on Duvalius (Biharotrechus) mallaszii rothi Jeannel (FI WR4221); ibidem, 5.VI.2012 - 12.VII.2013, J. Janák (by trap) (FI WR4220); Mts. Padurea Craiului, pestera Ciur Ponor, 27.V.2006, V. Zieris, on D. (B.) redtenbacheri bihariensis Csiki (FI WR4046); Muntii Apuseni, Valea Lesului, pestera cu Apa, 31.V.1996, J. Prouza, on various ventral parts of D. (B.) paroecus (J. Frivaldszky) (FI WR4491a); Bihor Mts., Ghetarul de sub Zgurasti, 12.VI.1988, V. Zieris, on various ventral parts of D. (B.) hickeri (Knirsch) (FI WR4490).

DESCRIPTION

Receptacle

Pale yellow, elongate, slender, sigmoid, with the main axis consisting of 25 to 50 cells separated by oblique septa. Basal cell brownish, distinctly curved, at least three times longer than broad; subbasal cell rectangular or trapezoidal, about half as long and slightly wider than the basal. Each cell of the axis above the basal bear a small trapezoidal cell which gives rise either to a long, dark appendage or to a pair of hyaline, slender antheridia with curved distal portion.

Perithecia

One or more, arising from the upper half of the main axis, dark yellow to light brown, elongate, narrowly elliptical to narrowly ovoid, ending in a blunt apex; perithecial stalk light yellow, cylindrical, variable in length, but usually about as long as the perithecial body.

Main axis

390-650 µm. Longest appendages 525 µm. Perithecium (including basal cells) 140-200 × 45-65 µm. Longest perithecial stalk 165 µm.

NOTES

With the five species described very recently ( Rossi & Christian 2020; Rossi & Leonardi 2020; Santamaria et al. 2020), the genus Rhachomyces has now about 90 species. Rachomyces neoproliferans W.Rossi & M.Leonardi , sp. nov. is easily distinguishable from all the other species in the same genus for the very many antheridia associated with few appendages, for the frequently ramified receptacle and for the number of stalked perithecia. The latter features are uncommon in the genus Rhachomyces and are usually associated with serious damage of the thallus.

The “new” species described here is undoubtedly the same taxon as the one already described from Romania as Rhachomyces proliferans by Lepesme (1941) on Duvalius (Biharotrechus) mallaszii (Csiki) ssp. gabriellae (Mallasz) and D. (B.) laevigatus (Bokor). The name Rhachomyces proliferans is not validly published because a Latin diagnosis is missing in the protologue (art. 39 of the International Code of Nomenclature for algae, fungi, and plants, 2018).

Unfortunately, the material on which Lepesme based his description has gone lost along with his entire slide collection (personal communication of Jean Balazuc to W. R.). After description, Rhachomyces proliferans was recorded by Bánhegyi (1949) on Duvalius (Biharotrechus) paroecus (J. Frivaldszky) and D. (B.) redtenbacheri (I. Frivaldszky von Frivald & J. Frivaldszky) and by Balazuc (1970) on D. (B.) cognatus (J. Frivaldszky).