Stigmatomyces scaptomyzae Thaxt.

Santamaria, Sergi & Pedersen, Jan, 2021, Laboulbeniomycetes (Fungi, Ascomycota) of Denmark, European Journal of Taxonomy 781, pp. 1-425 : 268-269

Stigmatomyces scaptomyzae Thaxt.

MB#179870

Fig. 61C–E

Proceedings of the American Academy of Arts and Sciences 36: 400 ( Thaxter 1901a). – Type: [Not designated] [Ind. loc.] “On the abdomen and legs of Scaptomyza graminum Fallen. Kittery Point , Maine, vicinity of Cambridge, Mass., Berkeley, California ”; FH. [ USA]

Diagnostic features

Basal cell of appendage dark, supporting a series of 5–6 cells, the lower flattened, darkened and sterile, the others bearing paired antheridia on their outer side, except for the upper cell which gives rise to three antheridia, the distal of which is spinose ( Fig. 61E ). Cell VII showing an outer enlargement of the wall which forms a sort of protrusion ( Fig. 61C–D , arrows). Perithecium with a somewhat cylindrical, and enlarged distally venter, and a well-distinguished, arcuate neck, which tapers distally into a distinct, slightly asymmetrical tip. [Detailed descriptions: Thaxter 1908; Majewski 1994b]

Distribution and hosts

This species is known from America ( USA, Venezuela), Africa ( Burundi), Asia ( Turkey) and Europe ( Portugal, Spain, France, Italy, Austria, Czech Republic, Slovakia, Poland and Finland) ( Majewski 2008). Subsequently reported from Afghanistan, Montenegro, Canada, Romania, and Germany ( Rossi & Máca 2006). Occurs on species of the genera Scaptomyza and Parascaptomyza ( Diptera Drosophilidae ) ( Rossi et al. 2019b).

Collections examined from Denmark

On Scaptomyza pallida (Zetterstedt, 1857) ( Diptera ; Drosophilidae ) DENMARK – Nordøstjylland (NEJ) • Laesø (Laboratorie have); 57°14.827′ N, 11°2.736′ E; PJ25; 10 Oct. 1970; Zool. Mus. Exp. Dry 0008; G. Bächli det.; ZMUC C-F-124021 • Sjaelland Northeast ; without coordinates; ca 1900; R.W. Schlick Dry0009; G. Bächli det.; ZMUC C-F-124022 .

Remarks

First record from Denmark. The presence of this species in Denmark is not surprising since it is very common and widely distributed. In Rossi et al. (2019b) it is written that Scaptomyza graminum and S. pallida “… were confused with each other for a long time and it seems possible that S. pallida is the ‘true’ host of Stigmatomyces scaptomyzae , while the ‘true’ Scaptomyza graminum is parasitized only by Stigmatomyces venetus ”.

Figures

Fig. 61. Stigmatomyces spp. A–B. S. purpureus Thaxt. Mature thalli. In A, arrows point to the two projections of the perithecial apex. – C–E. S. scaptomyzae Thaxt.C–D. Mature thalli showing protrusion of cell VII (arrows). E. Primary appendage in detail. Scale bars: A–D = 50 µm; E = 25 µm. Photographs from slides ZMUC C-F-124025 (A), ZMUC C-F-124026 (B), ZMUC C-F-124021 (C–E).