Pleosporales - CBS - KNAW

Fungal Diversity
hyaline small cells of textura epidermoidea, 2–4 μm diam.,
cell wall 1–3 μm thick, interspersed with interwoven
mycelium in places (Fig. 89b and c). Hamathecium of dense,
broadly trabeculate pseudoparaphyses 1–2 μm broad, anastomosing
between and above the asci (Fig. 89d). Asci 140–190
(−205)×12.5–15(−17.5) μm (x ¼ 164 14:3mm, n=10), 8-
spored, bitunicate, cylindrical, with a short, furcate pedicel,
20–45 μm long, and an inconspicuous ocular chamber (to
2 μm wide×1 μm high) (Fig. 89d and e). Ascospores 20–25×
10–12 μm (x ¼ 22:1 10:3mm, n=10), obliquely uniseriate
and partially overlapping, broadly ellipsoid with rounded
ends, hyaline, becoming pale brown when mature, 1-septate,
constricted at the median septum, smooth (Fig. 89f).
Anamorph: none reported.
Material examined: CHINA, Kansu Prov., between
Scharakuto and Kweite, on rotten stems of Salsola gemmascens
Pall., 25 Jul. 1935, G. Fenzel 2400 (W 16366, type).
Notes
Morphology
Sinodidymella was formally established by Yue and
Eriksson (1985) as they noticed that Amphididymella
verrucosa Petr. was not congeneric with the generic type,
A. adeana Petr., which is a pyrenolichen. Thus a new
monotypic genus, Sinodidymella was introduced to accommodate
it. The most outstanding morphological character of
Sinodidymella is its radial ridges, which are somewhat
comparable with that of Lophiostoma rugulosum Yin.
Zhang, J. Fourn. & K.D. Hyde, although their pseudoparaphyses
are dissimilar. Lophiostoma rugulosum has “tightly
aggregated cellular pseudoparaphyses” and “apically ending
into bunches of clavate cells” (Zhang et al. 2009b).
Phylogenetic study
None.
Concluding remarks
The radial ridges have little phylogenetic significance in
genus level classification (Zhang et al. 2009b), but the
broadly trabeculate pseudoparaphyses of Sinodidymella
may fit Melanommataceae.
Splanchnonema Corda, in Sturm, Deutschl. Fl., 3 Abt.
(Pilze Deutschl.) 2(9), Tome 3: 115 (1829). (?Pleomassariaceae)
Generic description
Habitat terrestrial, saprobic. Ascomata medium to large,
solitary or scattered, immersed in cortex with a pseudostromal
covering, with a small ostiole appearing on the host
surface, flattened subglobose. Peridium thin. Hamathecium
Fig. 87 Setomelanomma holmii (from UPS F-117969 (slide), isotype). b
a, b Asci with short pedicels in pseudoparaphyses. c Partial view of
ascus. d Branching and septate pseudoparaphyses. a Three-septate
lightly pigmented ascospores in ascus. Scale bars: a–e=10 μm
of dense, cellular pseudoparaphyses, embedded in mucilage,
anastomosing and branching. Asci bitunicate, fissitunicate,
clavate to broadly cylindrical, with a short,
narrowed, furcate pedicel. Ascospores clavate with a
rounded apex and acute base, reddish brown, constricted
at the septa.
Anamorphs reported for genus: Myxocyclus, Steganosporium
(Barr 1982b).
Literature: Barr 1982b, 1993a; Boise 1985; Corda 1829;
Eriksson 1981; Ramaley and Barr 1995; Shoemaker and
LeClair 1975; Sivanesan 1984; Tanaka et al. 2005.
Type species
Splanchnonema pustulatum Corda, in Sturm, Deutschl. Fl.,
3 Abt. (Pilze Deutschl.) 2(9), Tome 3: 115 (1829). (Fig. 90)
Ascomata 400–600 μm high×550–1000 μm diam.,
solitary or scattered, immersed in cortex with a pseudostromal
covering, with a small ostiole appearing on the host surface,
flattened subglobose (Fig. 90a). Peridium 15–25 μm thick,
composed of small lightly pigmented thin-walled compressed
cells (Fig. 90b). Hamathecium of dense, long cellular
pseudoparaphyses 2–3 μm broad, embedded in mucilage,
anastomosing and branching. Asci 200–250×30–
45 μm (x ¼ 219:6 38:2mm, n=10), 8-spored, bitunicate,
fissitunicate, clavate to broadly cylindrical, with a short,
narrowed, furcate pedicel up to 35 μm long, without
conspicuous ocular chamber (Fig. 90c and d). Ascospores
45–53×20–24 μm (x ¼ 48:5 22:3mm, n=10), obliquely
uniseriate and partially overlapping to biseriate, clavate
with a rounded apex and acute base, reddish brown, 2-
septate, apical cell largest, broader than the lower cells,
basal cell smallest, constricted at the septa, smoothwalled,
surrounded by a regular hyaline gelatinous
sheath, 3–6 μm thick (Fig. 90e and f).
Anamorph: none reported.
Material examined: UK, Avon, nr Bath, Batheaston, on
branch of Ulmus, C.E. Broome (L, No. 910.251-352, No.
910.251-371).
Notes
Morphology
A confusing outline of the history of Splanchnonema
was provided by Shoemaker and LeClair (1975), which at
the time was a valid, but little used name. Eriksson (1981)
and Sivanesan (1984) stated (without comment) that the
lectotype of Splanchnonema is S. pupula (Fr.) O. Kuntze.
However, S. pustulatum is listed as the generic type in the