Pleosporales - CBS - KNAW

Fungal Diversity
Fig. 35 Helicascus kanaloanus
(from Herb. J. Kohlmeyer No.
2566, holotype). a Section of
ascostroma immersed in the host
tissue. Note the torsellioid ostiole.
b One-septate, brown,
asymmetrical ascospores within
the asci. c, d Released thickwalled
ascospores. Note the
germ pore at the lower end of
the ascospores. Scale bars: a=
0.5 mm, b–d=20 μm
with a broad pore. Peridium composed of pseudoparenchymatous
cells. Hamathecium of dense, long pseudoparaphyses,
embedded in mucilage, septate, branching. Asci
cylindrical to cylindro-clavate, with a furcated pedicel.
Ascospores fusoid, ellipsoid or oblong with broadly to
narrowly round ends, 1-septate, constricted at the septum,
uni- to biseriate.
Anamorphs reported for genus: Pyrenochaeta or Pyrenochaeta-like
(Sivanesan 1984).
Literature: von Arx and Müller 1975; Barr1984; Cannon
1982; Freyer and van der Aa 1975; Mugambi and
Huhndorf 2009b; Samuels 1973; Samuels and Müller
1978; Sivanesan 1971, 1984.
Type species
Herpotrichia rubi Fuckel, Fungi rhenani exsic 2171.
(1868). (Fig. 36)
Ascomata 220–430 μm high×240–390(-530) μm
diam., scattered to gregarious, immersed to erumpent,
rarely superficial, globose to subglobose, wall black,
coriaceous, apex with a small sometimes inconspicuous
papilla, usually with a pore, lacking periphyses (Fig. 36a
and b). Peridium 32–45 μm wideatthesides,upto60μm
wide at the apex, basal wall thinner, all walls comprising
cells of textura angularis, cells 2.5–4 μm diam., cell wall
2–4(−7) μm thick, exterior cells more thick-walled and
pigmented, inner cells thin-walled and less pigmented,
comprising thin-walled cells up to 9 μm diam., apex cells
smaller and walls thicker (Fig. 36b and c). Hamathecium
of dense, long pseudoparaphyses, 2–3 μm broad, embedded
in mucilage, septate, branching (Fig. 36e). Asci 105–
150×12.5–15 μm (x ¼ 137:5 13:8mm, n=10), 8-spored,
bitunicate, fissitunicate, cylindrical to cylindro-clavate,
with a furcate pedicel that is 20–42.5 μm long, and
ocular chamber up to 2.5 μm wide×2.5 μm high
(Fig. 36d and f). Ascospores 17.5–25×(5.5-)6.3–9 μm
(x ¼ 20:5 7:3mm, n=10), biseriate to partially overlapping
uniseriate near the base, fusoid with narrowly
rounded ends, hyaline when immature and becoming pale
brown, 1-septate, deeply constricted at the septum, the
upper cell often broader than the lower one, verruculose
(Fig. 36g and h).
Anamorph: Pyrenochaeta rhenana Sacc. (Sivanesan
1984).
Material examined: AUSTRIA, on Rubus idaeus L.,
very rarely in the spring, in the Oestreicher meadow forest
(G, F. rh. 2171, type).