Zygospermella insignis (Mouton) Cain, Mycologia 27(2): 227 (1935)
MycoBank number: MB 267971; Index Fungorum number: IF 267971; Facesoffungi number: FoF 10027; Fig. 46
Coprophilous . Sexual morph : Ascomata 650–900 × 250–500 µm, perithecial, solitary, superficial to semi-immersed, carbonaceous to membranaceous, pyriform to subglobose, dark brown to black, verrucose, surrounded by setae, ostiolate, with black, carbonaceous necks 180–250 × 100–150 µm, inner cells with hyaline periphyses. Setae 2.5–4.5 µm wide, brown, aseptate, tapering towards the acute apex. Peridium 25–40 µm wide, outer layer composed of carbonaceous, brown to black cells of textura intricata to textura angularis; inner layer composed of membranaceous, hyaline cells of textura angularis to textura prismatica. Paraphyses 2.5–4.5 µm wide (x̄ = 3.5 µm, n = 30), unbranched, cylindrical, septate, tapering, slightly constricted at the septa. Asci (150–)200–240(–270) × 15–25 µm (x̄ = 220 × 20 µm, n = 20), 8-spored, unitunicate, cylindrical to subclavate, pedicellate, apex rounded and thickened. Ascospores uni- or bi-seriate, hyaline, aseptate, fusiform to ellipsoidal when young, becoming hourglass-shaped to elongate-subfusiform, ends truncate, 1-septate, sometimes 3-septae, constricted at the middle septum 3–7 µm wide, dark brown when mature, (26–)30–40(–45) × 7–10 µm (x̄ = 35 × 8 µm, n = 20), with a germ pore and appendage at each end. Appendages 4.5–8 µm wide, hyaline, cylindrical, tapering, ends rounded, smooth-walled, with longitudinally striate. Asexual morph: Undetermined.
Material examined: Canada, Ontario. Bear Island, Lake Temagami, on cow dung, 21 November 1933, R.F. Cain (BPI-618905).
Known hosts and distribution: On dung of cow, sheep and horse in Belgium (type locality), Canada, England, Norway, Scotland, Spain and Sweden (Mouton 1897; Lundqvist 1969).
Notes: We re-examined authentic material collected by Cain and determined by Lundqvist (mentioned in the label of material) since the type specimen was unavailable.
Fig. 46 Zygospermella insignis: a–k, m–p (BPI-618905); l (redrawn from Cain 1934). a Herbarium material. b Ascoma semi- immersed on host. c Vertical section of the neck. d Peridium. e Setae. f Asci with paraphyses. g Paraphyses. h, i Asci. j Apical ring of ascus. k–p Ascospores. Notes: f. i. j from permanent mount. Scale bars: b = 500 µm, f = 100 µm, c. d. h. i = 50 µm, e. g. k–p = 20 µm, j = 10 µm