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Page number:148 
Description type:Non-original description 
Description:Bionectria pityrodes (Mont.) Schroers, comb. nov. -- Figs 59 a-i, 60 a, b, 61 a, b.
Anamorph: Clonostachys pityrodes Schroers, stat. nov. -- Figs 59 b, 60 c-f, 61 c-g; Fig. 22 F in Samuels et al. (1990).
Type for Sphaeria pityrodes: Cuba. S. Marco; on bark of twigs (Montagne, 1856) (specimen not seen). Type for Clonostachys pityrodes: - Mauritius. Bois du Lait; on bark [dried culture ex CBS 102033 (= IMI 3663387, G.J.S. isolate 95-26), derived from ascospores of BPI 737867 and filed with it (BPI)].
Description from natural substratum: Stroma prosenchymatous, hyphal cells forming a textura porrecta. Perithecia formed on the stroma, or at the base of sporodochia, frequently also on the stroma of black pyrenomycetes, densely crowded in groups of 2 to up to 50, 300-600 µm diam, subglobose, subbasally and apically pinched when dry, yellowish orange to orange, with a warted surface. Perithecial warts small, orange; cells 4-13 — 3-10 µm, with uniformly thickened walls around 2 µm thick; adjacent cells with free space in between; vacuoles not observed. Perithecial wall 60-80 µm thick, consisting of three regions. Outer region 20-35 µm or 5-8 cells thick; cells angular to globose, continuous with the cells of the perithecial warts, not merging with the prosenchymatous stroma. Middle region 17-21 µm thick, consisting of several (up to 8) layers of intertwined hyphae, forming a textura intricata, conspicuous even in longitudinal sections. Inner region to 15-30 µm thick. Asci clavate to broadly clavate, (64-)80.5-89-97(-133) — (7.5-) 11.5-15-18.5(-23) µm (n = 41), frequently with a reduced number of ascospores; apex rounded, without a conspicuous ring. Ascospores slightly curved, bean-shaped, broadly rounded, ellipsoidal, equally two-celled, not constricted at the septum, smooth, rough, or very finely warted, particularly while in the ascus, somewhat brownish, (15.4-)24.2-26.8-29(-39.6) — (6.4-)8.2-9.2-10.2(-13.2) µm (n = 292), completely filling the ascus. Sporodochia flat or cupulate, olive-green because of the conidial masses, independently formed beside the perithecia or on or within the perithecial stroma, up to 650 µm wide and 450 µm high; margin of sporodochia white because of subhymenium mycelium or sterile marginal hyphae; base of the sporodochia prosenchymatous, erumpent through the bark, similar to the perithecial stroma; phialides and conidiophores densely aggregated in a textura porrecta. Sterile mycelium sometimes visible on the bark surface, white, surrounding the base of the perithecia or sporodochia.
Known distribution: Teleomorph frequent, pantropical. Anamorphic isolates unknown, although sporodochia sometimes occur without associated perithecia.
Habitat: On bark of recently dead woody plants, frequent on other pyrenomycetes.
Published descriptions: Samuels et al. (1990).
Taxon name: