Pleosporales - CBS - KNAW

Fungal Diversity
cells small heavily pigmented thick-walled cells of textura
angularis, cells 4–7 μm diam., cell wall 3.5–5 μm thick,
inner cells less pigmented, comprising thin-walled compressed
cells; apical wall cells smaller and walls thicker,
basal wall thinner (ca. 15μm wide), composed of lightly
pigmented thin-walled compressed cells (Fig. 50b and c).
Hamathecium of trabeculate pseudoparaphyses, 1–2 μm
broad, septate, anastomosing and branching rarely between
and mostly above the asci. Asci 105–130(−150)×10–15 μm
(x ¼ 123 12mm, n=10), 8-spored, bitunicate, fissitunicate
dehiscence not observed, clavate to cylindro-clavate, with a
short, narrow, furcate pedicel which is 10–25 μm long, and
a small inconspicuous ocular chamber (to 1.5 μm wide×
1 μm high) (Fig. 50d and e). Ascospores (80-)90–115×3–
5 μm (x ¼ 95 3:5mm, n=10), filliform, gradually tapering
towards the base, hyaline to light yellow, (6-)7(−8)-septate,
slightly constricted at each septum, smooth (Fig. 50f).
Anamorph: none reported.
Material examined: USA, New Jersey, Newfield, on
dead stems of Oenothera biennis, Aug. 1881, Ellis (NY
643, holotype, NY 885, isotype).
Notes
Morphology
Lophionema is a relatively poorly studied genus, which
was formally established by Saccardo (1883) as a monotypic
genus represented by L. vermisporum based on its “globose
ascomata, compressed ostiole, cylindrical to clavate ascus,
and filamentous, septate, subhyaline to lightly pigmented
ascospores”. Lophionema vermisporum was consequently
listed as the generic type (Clements and Shear 1931). Berlese
(1890) placed the genus in Lophiostomataceae but mentioned
that the genus was similar to Ophiobolus according to
the variable apex, and Shoemaker (1976) transferred Lophionema
vermisporum to Ophiobolus sensu lato. Chesters and
Bell (1970) however, had regarded Lophionema as related to
Lophiostoma despite the distinct ascospore morphology. Barr
(1992b) assignedLophionema to Entodesmium based on the
morphology of ascomata, papilla, peridium structure, pseudoparaphyses
as well as the hyaline or slightly yellowish
ascospores with a terminal appendage (not observed here).
Species of Entodesmium, however, exclusively occur on
legumes, but Lophionema vermisporum does not. We also
note that the filliform ascospores, bitunicate asci, pseudoparaphyses
and nature of the peridium may also be considered
as typical of genera in the Tubeufiaceae (Barr 1980;
Kodsueb et al. 2006b).
Phylogenetic study
None.
Concluding remarks
The immersed to erumpent ascomata, trabeculate pseudoparaphyses
and laterally flattened papilla and periphysate
ostioles indicate that this genus should be included in
Lophiostomataceae. We do not accept the above proposals
and, consider that Lophionema should be maintained as a
separate genus with filliform ascospores in Lophiostomataceae
until representative taxa can be sequenced and
analyzed. Currently Lophionema comprises 10 species
(http://www.mycobank.org, 08-01-2009). However, many
of these are poorly studied and obscure.
Lophiostoma Ces. & De Not., Comm. Soc. crittog. Ital. 1:
219 (1863). (Lophiostomataceae)
Generic description
Habitat terrestrial, saprobic. Ascomata immersed to erumpent,
usually with a distinct depressed papilla and a slotlike
ostiole. Hamathecium of dense, long, septate pseudoparaphyses,
embedded in mucilage, anastomosing and
branching between and above the asci. Peridium unequal
in thickness, thicker near the apex and thinner at base. Asci
usually clavate. Ascospores 1-septate, multi-septate or even
muriform, hyaline to deep brown, usually with terminal
appendages.
Anamorphs reported for genus: Pleuorphomopsis-like
(Hyde et al. 2011).
Literature: Barr 1990a; Chesters and Bell 1970; Holm and
Holm 1988; Hyde and Aptroot 1998; Hyde et al. 2002;
Tanaka and Harada 2003b; Yuan and Zhao 1994.
Type species
Lophiostoma macrostomum (Tode) Ces. & De Not.,
Comm. Soc. crittog. Ital. 1: 219 (1863). (Fig. 51)
≡ Sphaeria macrostoma Tode, Fung. mecklenb. sel.
(Lüneburg) 2: 12 (1791).
Ascomata 400–600 μm high×420–560 μm diam.,
densely scattered to gregarious, semi-immersed to erumpent,
globose or subglobose, with a small to large
flattenedcrest-likeraisedareaabovetheascomatawhich
is variable in shape, up to 300 μm high and 480 μm
wide, with a slit-like ostiole along the full length of the
crest (Fig. 51a and b). Peridium 30–45 μm thick at the
sides, thicker at the apex and thinner at the base,
composed of one cell type of small lightly pigmented
thin-walled cells of textura prismatica, cellsca. 6–9×3–
4 μm diam., apex composed of pseudoparenchymatous
cells (Fig. 51b). Hamathecium of dense, filliform, up to
3 μm near the base and less than 1.5 μm broad in the