Pleosporales - CBS - KNAW

Fungal Diversity
(Shoemaker and Babcock 1989b). Phaeosphaeria species
are usually associated or parasitic on annual monocots,
such as Cyperaceae, Juncaceae or Poaceae but have also
been recorded as saprobes and on dicotyledons (e.g. P.
viridella and P. vagans).
Phylogenetic study
The separation of Phaeosphaeria from Leptosphaeria
sensu stricto was supported by phylogenetic studies based
on ITS sequences. The peridium structure, pseudoparenchymatous
cells in Phaeosphaeria versus scleroplectenchymatous
cells in Leptosphaeria had phylogenetic
significance in the distinction between these two genera,
while the subgenus division was not supported by the
phylogenetic results (Câmara et al. 2002; Morales et al.
1995). The familial status of both Phaeosphaeriaceae and
Leptosphaeriaceae was verified by multigene phylogenetic
analysis (Schoch et al. 2009; Zhang et al. 2009a).
Concluding remarks
Phaeosphaeria was originally thought to be a synonym of
Leptosphaeria (Müller 1950; Munk1957), however, molecular
analysis has shown these two genera differ with
Phaeosphaeria having pseudoparenchymatous peridium, Stagonospora-like
anamorph and mostly monocotyledonous
hosts and Leptosphaeria having scleroplectenchymatous
peridium, Phoma-like anamorph and mostly dicotyledonous
hosts (Câmara et al. 2002;Schochetal.2009; Shoemaker and
Babcock 1989b; Zhang et al. 2009a). It is now recognized
that Phaeosphaeria is the type genus of Phaeosphaeriaceae
and related genera include Entodesmium and
Setomelanomma and probably Ophiosphaerella (Schoch
et al. 2009; Zhangetal.2009a). Paraphaeosphaeria was
introduced as an off-shoot of Phaeosphaeria and differs
in ascospore shape and septation as well as anamorphic
stages (Eriksson 1967a, b). Similarly, Nodulosphaeria
was recently reinstated and differs from Phaeosphaeria
because of setae over the apex as well as its ascospores
with swelling supramedian cells and terminal appendages
(Holm 1957, 1961). While the newly reinstated Phaeosphaeria
was confined to monocotyledons and particularly
grasses, there are now many species that have been
described from dicotyledons (Farr et al. 1989). Whether
these taxa form a monophyletic group needs to be
investigated with fresh collections and molecular data.
Phaeosphaeriopsis M.P.S. Câmara, M.E. Palm & A.W.
Ramaley, Mycol. Res. 107: 519 (2003). (Phaeosphaeriaceae)
Generic description
Habitat terrestrial, saprobic or hemibiotrophic? Ascomata
small, scattered or in small groups, immersed,
globose, subglobose. Peridium thin, comprising one cell
type of textura angularis. Hamathecium of dense, wide
cellular pseudoparaphyses. Asci 8-spored, bitunicate,
cylindrical to broadly fusoid, with a short pedicel and a
small ocular chamber. Ascospores obliquely uniseriate
and partially overlapping to biseriate even triseriate,
cylindrical, pale brown, multi-septate, primary septum
submedian, with or without constriction, verrucose or
baculate.
Anamorphs reported for genus: Coniothyrium-like,
Phaeostagonospora (Câmara et al. 2003).
Literature: Câmara et al. 2003.
Type species
Phaeosphaeriopsis glaucopunctata (Grev.) M.P.S. Câmara,
M.E. Palm & A.W. Ramaley, Mycol. Res. 107: 519 (2003).
(Fig. 75)
≡ Cryptosphaeria glaucopunctata Grev. Fl. Edin.: 362
(1824).
Ascomata 120–150 μm high×140–200 μm diam.,
scattered, or in small groups, immersed, globose, subglobose
(Fig. 75a). Peridium 10–25 μm wide, comprising one
type of cells, composed of thick-walled cells of textura
angularis, cells 4–9 μm diam., cell wall 2–3 μm thick,
almost equal in thickness. Hamathecium of dense, wide
cellular pseudoparaphyses, 3–5 μm broad. Asci (50-)60–
110×10–15 μm (x ¼ 82:3 12mm, n =10), 8-spored,
bitunicate, fissitunicate dehiscence not observe, cylindrical
to broadly fusoid, with a short pedicel, with a small
ocular chamber (to 0.8 μm wide×1 μm high) (Fig. 75b).
Ascospores 18–28×5–7.5 μm (x ¼ 23:5 6:2mm, n=10),
obliquely uniseriate and partially overlapping to biseriate
even triseriate, cylindrical, pale brown, 4(−5)-
septate, without constriction or slightly constricted at
the basal septum, the forth cell from the apex usually
slightly inflated, the basal cell often longer, baculate
(Fig. 75c, d, e and f).
Anamorph: none reported.
Material examined: UK, Epping, Sept. 1863 (E, M.C.
Cooke 166, barcode: E00074286).
Notes
Morphology
Phaeosphaeriopsis was introduced to accommodate
some species of Paraphaeosphaeria based on both morphological
characters and results of SSU rDNA sequence
analyses (Câmara et al. 2003). Most of the Phaeosphaeriopsis
species occur on the Agavaceae, although P.
glaucopunctata occurs on Liliaceae (Ruscus). Phaeosphaeriopsis
is characterized by having uni- or multioculate
stromata and 4- or 5-septate ascospores. Although the