Pleosporales - CBS - KNAW

Fungal Diversity
Dubitatio Speg., Anal. Soc. cient. argent. 12: 212
(1881). (Arthopyreniaceae (or Massariaceae))
Generic description
Habitat terrestrial, saprobic. Ascomata medium-sized, solitary,
densely scattered, or in small groups of 2–4,
immersed, covered with white crystaline rim, papillate,
ostiolate. Hamathecium of dense pseudoparaphyses, long,
2–3 μm broad, branching and anastomosing. Asci cylindrical,
pedicellate, with furcate pedicel. Ascospores 1-septate,
asymmetrical, reddish to dark brown.
Anamorphs reported for genus: Aplosporella-like (Rossman
et al. 1999).
Literature: Barr 1979b, 1987b; Müller and von Arx 1962;
Rossman et al. 1999; Spegazzini 1881.
Type species
Dubitatio dubitationum Speg., Anal. Soc. cient. argent. 12:
212 (1881). (Fig. 29)
Ascomata 350–530 μm high×550–700 μm diam.,
solitary, densely scattered, or in small groups of 2–4,
immersed, with a protruding papilla, 110–160 μm high,
160–250 μm diam., globose or subglobose, black,
covered with white crystalline material which becomes
hyaline and gel-like in water, ostiolate (Fig. 29a and b).
Peridium 18–25 μm thick laterally (excluding the rim), up
to 35 μm thick at the apex, thinner at the base, 1-layered,
composed of small pale brown thin-walled cells of textura
prismatica, cells 5–12×3–5 μm diam., cell wall up to
1 μm thick, apex cells smaller and walls thicker
(Fig. 29b). Hamathecium of dense, long pseudoparaphyses,
2–3 μm broad, branching and anastomosing between
and above the asci. Asci 150–190(−230)×12.5–15 μm
(x ¼ 172:5 13:4mm, n =10), (6-)8-spored, rarely 4-
spored, bitunicate, fissitunicate, cylindrical, with a furcate
pedicel which is up to 40 μm long, ocular chamber not
observed (Fig. 29c, d and e). Ascospores 19–22.5×10–
12 μm (x ¼ 20:2 11:4mm, n=10), uniseriate to obliquely
uniseriate and partially overlapping, broadly ellipsoid
with broadly to narrowly rounded ends, reddish brown,
1-septate, constricted at septum, asymmetric with a
larger upper cell, thick-walled, possibly distoseptate
(Fig. 29f, g and h).
Anamorph: Aplosporella-like (for detailed description
see Rossman et al. 1999).
Conidiomata globose, ca. 300 μm diam. Conidia
holoblastic, broadly fusoid, 13–15×7–10 μm, dark brown,
finely spinulose (Rossman et al. 1999).
Material examined: ARGENTINA, Buenos Aires,
Tuyu, on Celtis tala Gill., Jan. 1881, leg. det. C. Spegazzini
(NY, isotype; LPS, holotype).
Notes
Morphology
When established Dubitatio, Spegazzini (1881) considered
it as intermediate between Sphaeriaceae and Nectriaceae
as has been mentioned by Rossman et al. (1999). Müller
and von Arx (1962) treated Dubitatio as a synonym of
Passerinula, while the differences of ascomata and ascospores
could easily distinguish these two genera (Rossman et al.
1999). After checking the type specimen, Dubitatio was assigned
to Dothideomycetes, and considered closely related to Dothivalsaria
in the Massariaceae (Barr 1979b, 1987b). Dubitatio
chondrospora was assigned to Pseudomassaria (as P. chondrospora
(Ces.) Jacz.) (Barr 1964; Müller and von Arx 1962).
Phylogenetic study
None.
Concluding remarks
The black ascomata with white crystalline covering and
central white ostiolar region as well as the asymmetrical
reddish brown ascospores are striking characters of Dubitatio
dubitationum. The genus cannot be assigned to any
family with certainty based on morphological characters
and fresh collections are needed for sequencing.
Entodesmium Reiss, Hedwigia 1: 28 (1854).
(Phaeosphaeriaceae)
Generic description
Habitat terrestrial, saprobic (or parasitic?). Ascomata
scattered or in small groups, immersed, papillate, ostiolate,
periphysate. Peridium thin, comprising one cell type of
pigmented pseudoparenchymatous cells. Hamathecium of
dense, long pseudoparaphyses, septate, embedded in mucilage.
Asci 8-spored, bitunicate, fissitunicate, cylindrical, with
furcate pedicel. Ascospores ellipsoid to filliform, multiseptate,
deeply constricted at the primary septum (usually
near apex), breaking into partspores.
Anamorphs reported for genus: none.
Literature: von Arx and Müller 1975; Barr1992b; Eriksson
1967a; b; Holm1957; Liewetal.2000; Shoemaker 1984a, b.
Type species
Entodesmium rude Reiss, Hedwigia 1: 28 (1854). (Fig. 30)
Ascomata 160–250 μm high×150–300 μm diam., in groups,
immersed with long and protruding cylindrical papilla,
globose to subglobose, black, coriaceous (Fig. 30a). Papilla
100–220 μm long, 70–120 μm broad, cylindrical, with
periphysate ostiole. Peridium 25–33 μm wide, comprising
pseudoparenchymatous cells, cells up to 10×7.5 μm diam., cell
wall up to 2 μm thick, beak cells smaller and wall thicker