Pleosporales - CBS - KNAW

Fungal Diversity
immersed in host tissue, coriaceous, globose or subglobose,
usually a somewhat thick, short papilla, up to
100 μm high, with a pore-like ostiole (Fig. 69a). Peridium
27–35 μm thick laterally, up to 55 μm thick at the apex, 1-
layered, composed of small pigmented cells of textura
angularis, cells up to 5×8 μm diam., cell wall 1.5–2 μm
thick, apex cells smaller and walls thicker (Fig. 69b).
Hamathecium of dense, long trabeculate pseudoparaphyses,
1–1.5 μm broad, anastomosing and branching between
and above the asci. Asci 150–208×17.5–25 μm
(x ¼ 182:5 22mm, n=10), 8-spored, bitunicate, fissitunicate,
cylindrical to cylindro-clavate, with a narrowed, furcate,
thin pedicel, 15–55 μm long, 2–3.5 μm broad, with a large
truncate ocular chamber best seen in immature asci (to 4 μm
wide×3 μm high) (Fig. 69e, f and g). Ascospores 55–72.5×
10–12 μm (x ¼ 63 10:4mm, n=10), 3–4 seriate to uniseriate
near the base, cylindrical to clavate, with broadly to
narrowly rounded ends, brown, 6–7 transversesepta,easily
separating into partspores, with germ slits, central partspores
of the ascospores shorter than broad, rectangular in vertical
section, round in transverse section, 7–8×6–10 μm diam.,
apical cells usually longer than broad, 11–17.5×6–7 μm
diam. (Fig. 69c and d).
Anamorph: none reported.
Material examined: USA, Albuquerque, Bernalillo Co.,
New Mexico, dry gravelly hill, on wood, 29 Nov. 1901, T.
S.A. Cockerell (NY, holotype).
Notes
Morphology
Ohleriella was formally established by Earle (1902) based
on its “medium to large ascomata with a wide papilla,
relatively wide peridium, cylindro-clavate asci, brown to
deep brown multi-septate ascospore, with elongated germ slit
on each cell”, and was monotypified by O. neomexicana
(Barr 1990a). Ohleriella subsequently has been treated as a
synonym of Ohleria, Sporormiella or Preussia (Ahmed and
Cain 1972; vonArxandMüller1975; Clements and Shear
1931). Spororminula tenerifae, the generic type of Spororminula,
was assigned to Ohleriella, thus Spororminula was
treated as a synonym of Ohleriella (Barr 1990a). Two new
species were introduced by Barr (1990a) from North America.
Currently, three species are included in this genus, i.e. O.
herculean (Ellis & Everh.) M.E. Barr, O. neomexicana and O.
nudilignae M.E. Barr & Malloch (http://www.index
fungorum.org; http://www.mycobank.org, 01/03/2009).
The generic type, O. neomexicana, is morphologically
similar to the coprophilous genus Sporormiella, but is
saprobic on grass stems.
Phylogenetic study
None.
Concluding remarks
Although we maintain Ohleriella as a separate genus
here, its saprobic habitat on grasses and similarity to the
coprophilous Sporormiella may indicate a close evolutionary
relationship, with the grass saprobic possibly
being an early relative of the coprophilous Sporormiella.
Alternatively, the species/genera may simply occupy
different ecological niches (i.e. dead grass vs dead grass
in dung). Molecular studies are needed to resolve this
issue.
Ophiobolus Reiss, Hedwigia 1:27 (1854).
(Phaeosphaeriaceae)
Generic description
Habitat terrestrial, saprobic or hemibiotrophic. Ascomata
medium-sized, solitary, scattered, or in groups, globose or
pyriform, coriaceous, black, papillate, ostiolate, periphysate.
Peridium thin, thicker near the apex, thinner at the base.
Hamathecium of long cellular pseudoparaphyses, septate,
anastomosing or branching not observed. Asci 8-spored,
bitunicate, fissitunicate dehiscence not observed, cylindrical,
with a short, furcate pedicel. Ascospores filamentous,
narrower toward the lower end, pale brown, multiseptate,
separating into two partspores from the middle
septum, from the breaking point, the second cell of each
partspore enlarged.
Anamorphs reported for genus: Coniothyrium-like,
Rhabdospora, Phoma-like and Scolecosporiella (Hyde et
al. 2011; Shoemaker 1976; Sivanesan 1984).
Literature: Holm 1948, 1957; Müller 1952; Reiss 1854;
Shoemaker 1976; Sivanesan 1984.
Type species
Ophiobolus disseminans Reiss, Hedwigia 1:27 (1854)
(Fig. 70).
Ascomata 220–380 μm high×290–430 μm diam., solitary,
scattered, or in groups often arranged in a row, immersed with
a protruding papilla, globose, pyriform, coriaceous, black,
periphysate. Papilla 40–90 μm high, with a pore-like ostiole
(Fig. 70a and b). Peridium 40–55 μm wide at the sides, up to
70 μm thick at the apex, thinner at the base, comprising two
cell types, outer layer composed of small heavily pigmented
thick-walled cells of textura angularis, cells 2–5 μm diam.,
cell wall 2–3 μm thick, apex cells smaller and walls thicker,
inner layer composed of lightly pigmented or hyaline thinwalled
cells of textura angularis, 5–7 μm diam., wall 1.5–
2 μm thick, merging with pseudoparaphyses (Fig. 70c).
Hamathecium of long cellular pseudoparaphyses, 2–3 μm
broad, septate, anastomosing or branching not observed
(Fig. 70e). Asci 150–195×8–12.5 μm (x ¼ 169:5 10:7mm,