Pleosporales - CBS - KNAW

Fungal Diversity
Notes
Morphology
Byssosphaeria was introduced by Cooke and Plowright
(1879) based on its superficial ascomata seated on a “tomentose
subiculum of interwoven threads”, which includes various
species in Sphaeria and Byssisedae, and was validly typified by
B. keitii (Cooke 1878). Byssosphaeria keitii was treated as a
synonym of B. schiedermayeriana (Fuckel) M.E. Barr by
Sivanesan (1971), and B. schiedermayeriana exclusively occurs
in tropical regions or greenhouse environments in temperate
regions (Barr 1984). Morphologically, B. keitii is characterized
by its large ascomata with orange to reddish plain apices, and is
closely related to B. rhodomphala (Berk.) Cooke (Barr 1984).
For a long time, Byssosphaeria was assigned to
Herpotrichia sensu lato, and Byssosphaeria schiedermayeriana
was renamed as H. schiedermayeriana Fuckel
(von Arx and Müller 1975; Bose 1961; Luttrell 1973;
Müller and von Arx 1962; Sivanesan 1971). After studying
Herpotrichia in North America, Barr (1984) accepted a
relatively narrow generic concept, Herpotrichia sensu
stricto, and revived Byssosphaeria; this proposal is
supported by phylogenetic study (Mugambi and Huhndorf
2009b). Currently Byssosphaeria comprises 32 species
(http://www.mycobank.org, 08-01-2009).
Phylogenetic study
The monophyletic nature of Byssosphaeria is well
demonstrated, as well as its familial status in Melanommataceae
(Mugambi and Huhndorf 2009b).
Concluding remarks
Orange and greenish plain apices exist in the specimen
we examined, which is different from records as “orange,
bright or dull reddish plain apices” by Barr (1984). This
might be because different specimens have different
colours, or there may be a variation of apical colour within
a single species, as both orange and green can coexist on
the same ascoma (see Fig. 17a). The coloured apical rim,
together with the trabeculate pseudoparaphyses as well as
the presence of subiculum make Byssosphaeria readily
distinguishable from other morphologically comparable
genera, e.g. Herpotrichia and Keissleriella (Hyde et al. 2000).
Calyptronectria Speg., Anal. Mus. nac. Hist. nat. B. Aires
19: 412 (1909). (Melanommataceae)
Generic description
Habitat terrestrial, saprobic. Ascomata small- to mediumsized,
solitary, scattered, or in small groups, immersed,
lenticular to subglobose, papillate, ostiolate. Hamathecium
of long, filliform pseudoparaphyses, branching and anastomosing,
embedded in mucilage. Asci 4- to 8-spored,
bitunicate, fissitunicate, cylindrical to cylindro-clavate, with
a short, furcate pedicel. Ascospores muriform, broadly
fusoid to fusoid with broadly to narrowly rounded ends,
hyaline.
Anamorphs reported for genus: none.
Literature: Barr 1983; Rossman et al. 1999; Spegazzini
1909.
Type species
Calyptronectria platensis Speg., Anal. Mus. nac. Hist. nat.
B. Aires 19: 412 (1909). (Fig. 18)
Ascomata 120–270 μm high×170–400 μm diam., solitary,
scattered, immersed, lenticular to subglobose, papillate,
ostiolate (Fig. 18a and b). Apex with a small and slightly
protruding papilla. Peridium 18–30 μm wide, comprising two
types of cells, outer layer composed of pseudoparenchymatous
cells, cells 3–6 μm diam., cell wall 1–2 μm thick, inner
layer comprising less pigmented cells, merging with pseudoparaphyses
(Fig. 18b and c). Hamathecium of long, filliform
pseudoparaphyses, 1–2 μm broad, branching and anastomosing,
embedded in mucilage. Asci 98–140×12.5–20 μm
(x ¼ 107 15:4mm, n=10), 8-spored, sometimes 4-spored,
bitunicate, fissitunicate, cylindrical to cylindro-clavate, with
a short, furcate pedicel, 12–20 μm long,withanocular
chamber (to 4 μm wide×3 μm high) (Fig. 18e and f).
Ascospores 17– 22.5 μ m ×(6.3-)7.5– 10 μ m
(x ¼ 19:8 7:6mm, n=10), biseriate above and uniseriate
below, ellipsoid to broadly fusoid with broadly to narrowly
rounded ends, hyaline, usually with (3-)5 transverse septa,
with or without 1–3 longitudinal septa in the central cells,
constricted at the median septum, the upper cell often broader
than the lower one, smooth, surrounded by an irregular
hyaline gelatinous sheath up to 3 μm thick (in dry specimen)
(Fig. 18d).
Anamorph: none reported.
Material examined: ARGENTINA, La Plata, on decaying
branches of Manihot carthaginensis (Jacq.) Müll., Sept.
1906, Spegazzini (LPS 1209, holotype).
Notes
Morphology
Calyptronectria is a relatively poorly studied genus,
which was formally established based on C. argentinensis
Speg. and C. platensis, with C. platensis being chosen as
the generic type (Spegazzini 1909). Morphologically,
Calyptronectria is characterized by its immersed ascomata,