Pleosporales - CBS - KNAW

Fungal Diversity
Concluding remarks
Acrocordiopsis, Astrosphaeriella sensu stricto, Mamillisphaeria,
Caryospora and Caryosporella are morphologically
similar as all have very thick-walled carbonaceous ascomata,
narrow pseudoparaphyses in a gelatinous matrix (trabeculae)
and bitunicate, fissitunicate asci. Despite their similarities, the
shape of asci and ascospores differs (e.g. Mamillisphaeria has
sac-like asci and two types of ascospores, brown or hyaline,
Astrosphaeriella has cylindro-clavate asci and narrowly fusoid
ascospores, both Acrocordiopsis and Caryosporella has
cylindrical asci, but ascospores of Caryosporella are reddish
brown). Therefore, the current familial placement of Acrocordiopsis
cannot be determined. All generic types of Astrosphaeriella
sensu stricto, Mamillisphaeria and Caryospora
should be recollected and isolated for phylogenetic study.
Aigialus Kohlm. & S. Schatz, Trans. Br. Mycol. Soc. 85:
699 (1985). (Aigialaceae)
Generic description
Habitat marine, saprobic. Ascomata mostly subglobose in
front view, fusoid in sagittal section, rarely subglobose,
scattered, immersed to erumpent, papillate, ostiolate, ostiole
rounded or slit-like, periphysate. Peridium 2-layered. Hamathecium
of trabeculate pseudoparaphyses. Asci 8-spored,
cylindrical, pedicellate, with an ocular chamber and conspicuous
apical ring. Ascospores ellipsoidal to fusoid, muriform,
yellow brown to brown, with terminal appendages.
Anamorphs reported for genus: none.
Literature: Eriksson 2006; Jones et al. 2009; Kohlmeyer
and Schatz 1985; Lumbsch and Huhndorf 2007.
Type species
Aigialus grandis Kohlm. & S. Schatz, Trans. Br. Mycol.
Soc. 85: 699 (1985). (Fig. 2)
Ascomata 1–1.25 mm high×1–1.3 mm diam. in front view,
250–400 μm broad in sagittal section, vertically flattened
subglobose, laterally compressed, scattered, immersed to semiimmersed,
papillate, with an elongated furrow at the top of the
papilla, wall black, carbonaceous, ostiolate, ostiole filled with
branched or forked septate periphyses (Fig. 2a). Peridium 70–
100 μm thick laterally, up to 150 μm thick at the apex, thinner
at the base, comprising two cell types, outer layer composed of
small heavily pigmented thick-walled pseudoparenchymatous
cells, cells 1–2 μm diam., cell wall 2–5 μm thick, inner layer
thin, composed of small hyaline cells (Fig. 2b). Hamathecium
of dense, very long trabeculate pseudoparaphyses, 0.8–1.2 μm
broad, embedded in mucilage, anastomosing and branching
above the asci. Asci 450–640×22–35 μm (x ¼ 505 30mm,
n=10), 8-spored, bitunicate, fissitunicate, cylindrical to
cylindro-clavate, with a long furcate pedicel, 90–180 μm long,
with a low truncate ocular chamber and a refractive apical
apparatus (to 12 μm wide×4 μm high) (Fig. 2e and f).
Ascospores 75–95×15–26 μm (x ¼ 84:3 17:5mm, n=10),
obliquely uniseriate and partially overlapping, broadly fusoid
to fusoid with narrowly rounded ends in front view, flat on one
side from side view (14–20 μm thick), yellowish brown, apical
cells usually hyaline, muriform, with 14–17(−18) transversal
septa, 1–3 longitudinal septa in most cells, slightly constricted
at the septa, with a gelatinous cap at each end (Fig. 2c and d).
Anamorph: none reported.
Material examined: BELIZE, Wee-Wee Cay, on submerged
wood of roots and branches of Rhizophora mangle
L., Mar. 1983, leg. J. Kohlmeyer (NY, J.K. 4332b, isotype).
Notes
Morphology
Aigialus was formally established by Kohlmeyer and Schatz
(1985) based on its immersed or semi-immersed ascomata
with periphysate ostiole, trabeculate pseudoparaphyses, cylindrical
and fissitunicate asci, and distinctive muriform ascospores
with gelatinous sheath or caps. There are five accepted
species in the genus, namely A. grandis, A. mangrovei Borse,
A. parvus S. Schatz & Kohlm., A. rhizophorae Borse and A.
striatispora K.D. Hyde (Jones et al. 2009). Aigialus was first
assigned to the Melanommatales, but its familial status was
uncertain (Kohlmeyer and Schatz 1985). Barr (1990b)
included Aigialus in Massariaceae based on its conspicuous
apical ring in the asci and ascospore characters, and this has
subsequently been widely followed (Eriksson 2006; Hawksworth
et al. 1995; Kirk et al. 2001; Lumbsch and Huhndorf 2007).
Phylogenetic study
The generic type of Aigialus (A. grandis) together with
other three marine species, i.e. A. mangrovei, A. parvus as well
as A. rhizophorae form a robust clade on the phylogenetic
tree. Thus a new family, Aigialaceae, was introduced to
accommodate Aigialus together with Ascocratera and Rimora
(Suetrong et al. 2009).
Concluding remarks
The pleosporalean status of Aigialus has been phylogenetically
verified, and the single branch containing Aigialus,
Ascocratera and Rimora represents a familial rank of
Aigialaceae (Suetrong et al. 2009).
Amniculicola Yin. Zhang & K.D. Hyde, Mycol. Res. 112:
1189 (2008). (Amniculicolaceae)
Generic description
Habitat freshwater, saprobic. Ascomata solitary, scattered,
or in small groups, initially immersed, becoming erumpent,