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Department of Plant Taxonomy & Biosystematics, Institute of Botany, Academy of Science, Pr
honice 252 43, Czech Republic
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ABSTRACT |
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The new genus Barbatosphaeria is described for a perithecial ascomycete known as Calosphaeria barbirostris occurring on decayed wood of deciduous trees under the periderm. The fungus produces nonstromatic perithecia with hyaline, 1-septate ascospores formed in unitunicate, nonamyloid asci. Anamorphs produced in vitro belong to Sporothrix and Ramichloridium with holoblastic-denticulate conidiogenesis; conidiophores of the two types were formed in succession during the development of the colony. Phylogenetic analyses of nuLSU rDNA sequences indicate that this fungus is distinct from morphologically similar Lentomitella, tentatively placed in the Trichosphaeriales. It groups with freshwater Aquaticola and Cataractispora and terrestrial Cryptadelphia in maximum parsimony analysis; the same grouping but without Cryptadelphia was inferred from Bayesian analysis. Cultivation, morphology and phylogenetic studies of the nuLSU rDNA support the erection of a new genus for C. barbirostris.
Key words: Calosphaeriales, holoblastic-denticulate conidiogenesis, Lentomitella, Ramichloridium, Sporothrix
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INTRODUCTION |
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, Samuels and Blackwell 2001, Réblová et al 2004, Vijaykrishna et al 2004, Mostert et al 2006, Réblová and Mostert 2007). The Calosphaeriales s. str. recently were proposed to accommodate six genera and two families, the Calosphaeriaceae and Pleurostomataceae. The anamorphs have been referred to three new phialidic hyphomycetous genera based on the results of in vitro studies (viz. the Calosphaeriophora anamorph of Calosphaeria, the Phaeocrella anamorph of Togniniella and the Pleurostomophora anamorph of Pleurostoma).
In accordance with recent discoveries in the Calosphaeriales, studies in the genus Calosphaeria revealed significant differences in teleomorph morphology and associated anamorphs of taxa currently placed in the genus. Calosphaeria, based on the type species C. pulchella (Pers. : Fr.) J. Schröt., is delimited to species with dark, globose perithecia arranged in circular groups with necks radiating, usually decumbent, piercing the periderm together but not united in a disk; stipitate asci without visible discharge mechanism arising from short cells on ascogenous hyphae; hyaline allantoid ascospores and phialidic conidiogenesis (Réblová et al 2004). The Calosphaeriophora pulchella Réblová et al anamorph was linked experimentally to C. pulchella. The species that do not match the concept of Calosphaeria s. str. and the Calosphaeriales s. str. however remain in limbo and require taxonomic revision and a new placement after molecular and cultivation studies. However life histories of only two of the 106 species currently referred to Calosphaeria, with teleomorph morphology different than described for its core species, are known (viz. Calosphaeria faginea Samuels & Candoussau [Samuels and Candoussau 1996] and Calosphaeria barbirostris [Dufour : Fr.] Ellis & Everh. [this study]); both are species with holoblastic-denticulate conidiogenesis. Their relationship to the core species of Calosphaeria is unknown, and it thought that they might represent an evolutionary lineage close to the Diatrypales (Samuels and Candoussau 1996). The fact that there is little information about anamorphs of Calosphaeria spp. could be explained by their generally inconspicuous habitus and the fact that they usually are collected by coincidence when searching for other periderm-inhabiting fungi.
Recent collection of fresh material that is in complete agreement with the type specimen of C. barbirostris has provided the opportunity to evaluate this species and thus genus Calosphaeria. The conspicuous characters of C. barbirostris are long-necked, dark perithecia covered with reddish to olive-brown pubescence; short-ellipsoidal to oblong, 2-celled, hyaline ascospores; clavate, stipitate asci with a shallow apical annulus floating freely in the centrum at maturity, and holoblastic conidiogenesis. The great variability in disposition of perithecia of C. barbirostris on the natural substratum (i.e. small circular groups, large loosening oval to circular groups or perithecia in dense rows or growing solitarily) resulted in the fact that the species until now has been described under four generic taxonomic synonyms and combined under eight pyrenomycetous genera. However since the study of Ellis and Everhart (1892) the species C. barbirostris has been accepted in Calosphaeria because of the combined attributes of ascospore characters and perithecia with decumbent to perpendicular necks disposed in circular groups on the substratum. The link to an anamorph of C. barbirostris has not been proven in vitro. Höhnel (1908) reported 2–3-celled, brown conidia formed by septation of hairs on the perithecial neck. Barr (1985) observed 1-celled, brown conidia delimited from conidiogenous cells of conidiophores that clothe the neck. Similar observations also were described by Munk (1957) as 3-celled, brown, balloon-shaped conidia arising along hairs. The cultivated anamorph of C. barbirostris (this study) produced two kinds of conidiophores during the development of the colony. On early developed aerial hyphae short, hyaline, micronematous to semimacronematous conidiophores of the Sporothrix type were formed while later (in ca. 21 d at room temperature) macronematous conidiophores of the Ramichloridium type bearing a terminal rachis of conidia were formed in the center of the colony from where they spread over the whole colony.
Among the well known perithecial ascomycetes C. barbirostris resembles the terrestrial Lentomitella (Réblová 2006), C. faginea and C. dryina (Samuels and Candoussau 1996) and the freshwater Aquaticola, especially in the ascospores and long-necked, dark nonstromatic perithecia growing solitarily or in small groups on the substratum. The anamorph of Lentomitella is referred to as holoblastic-denticulate phaeoisaria-like (Réblová 2006); the anamorphs of C. faginea were described as Ramichloridium and Sporothrix, while the anamorph of Aquaticola is still unknown (Ho et al 1999).
Cultivation experiments, revision of the type and other herbarium material and phylogenetic studies of the nuclear LSU ribosomal DNA (nuLSU rDNA) (viz. maximum parsimony, parsimony ratchet and Bayesian analysis) support the erection of a new genus for C. barbirostris.
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MATERIALS AND METHODS |
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Single-ascospore isolates were obtained from fresh material with the aid of a single-spore isolator (Meopta, Prague, Czech Republic). Cultures were grown on potato-carrot agar (PCA, Gams et al 2007). Colonies were examined after 3, 7 and 21 d at 25 C in 12 h UV/ fluorescent light and 12 h dark. Cultures are maintained at CBS, Centraalbureau voor Schimmelcultures, Utrecht, The Netherlands, and in the Institute of Botany, Academy of Sciences, Prhonice.
DNA extraction, amplification and sequencing.— –
Methods for DNA extraction, amplification and sequencing of the first two-thirds of the nuLSU rDNA (1600 bp, although only 1275 bp were used for the analysis to match the length of other sequences) were identical to those described by Réblová and Seifert (2004).
Sequence data analyses.— –
Phylogenetic relationships were examined with 82 nuLSU rDNA sequences from 16 orders or families of the Sordariomycetes. Members of the Dothideomycetes were used as outgroup in all maximum parsimony, parsimony ratchet and Bayesian analyses. A new nuLSU rDNA sequence of Calosphaeria barbirostris (Gen-Bank EF577059) was obtained from the ascospore isolate. Other homologous sequences were retrieved from Gen-Bank; accession numbers are provided (FIGS. 1, 2).
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). Predicted models of the secondary structure of the LSU (Gutell et al 1993) molecules of Saccharomyces cerevisiae were used to improve the alignment. The models of the secondary structure of the LSU were highly consistent in all taxa and were comparable with that of S. cerevisiae. The alignments are available in TreeBase as SN3351. Phylogenetic analyses.— – Maximum parsimony, parsimony ratchet and Bayesian analyses were used to estimate phylogenetic relationships of C. barbirostris among all taxa investigated. For all analyses the first 75 characters were excluded from the alignment because of the incompleteness of 5' end of the majority of the available sequences.
Maximum parsimony and parsimony ratchet.— –
Maximum parsimony analysis was conducted with PAUP* 4.0b10 (Swofford 2002). A heuristic search was performed with stepwise-addition option with 1000 random taxon addition replicates and TBR branch swapping. All characters were unordered and given equal weight. Gaps were treated as missing data.
As an additional assessment of the search strategy, the parsimony ratchet (Nixon 1999) was performed to search efficiently for a shorter maximum parsimony consensus tree. PAUPRat (Sikes and Lewis 1991) was used in conjunction with PAUP*, with 20 batches of 300 iterations completed with 15% of the characters perturbed at each iteration. Of those MPT found compatible with the MPT from heuristic analysis, the final MPT were filtered out to fit the criteria of the best tree found.
Branch support was estimated on the recovered topologies performing 1000 bootstrap replicates with a full heuristic search, consisting of 10 random-addition replicates for each bootstrap replicate.
Bayesian analysis.— –
Bayesian analysis was performed in a likelihood framework as implemented by MrBayes v3.0b4 software package to reconstruct phylogenetic trees (Huelsenbeck and Ronquist 2001). Because Modeltest 3.5 (Posada and Crandall 1998) indicated that the GTR+I+G substitution model best fits the model of DNA evolution for our data the parameters in MrBayes were set as lset nst = 6 and rates = gamma.
Multiple Bayesian searches with Metropolis-coupled Markov chain Monte Carlo sampling were conducted. One cold and three heated Markov chains were used in the analysis. Bayesian analysis was run for 5 000 000 generations, with trees sampled every 100 generations. The first 20 000 trees, which represented the burn-in phase of the analysis, were discarded. To estimate posterior probabilities (pP) of recovered branches (Larget and Simon 1999) 50% majority rule consensus trees were created from the remaining trees with PAUP*.
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RESULTS |
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). Of the 419 MPT recovered by parsimony ratchet, 77 MPT were filtered out to fit the criteria of the best tree found. The 77 MPT had identical topologies and tree lengths (3144) as did the one MPT inferred by the heuristic search in parsimony analysis.
The one MPT consisted of two major lineages, the Hypocreales/Microascales (87% bootstrap support) and the rest of sampled perithecial ascomycetes forming seven major clades. Calosphaeria barbirostris resided within the latter lineage in a clade (with no branch support) being a sister of the two species of Cryptadelphia (100%) to the freshwater Aquaticola and Cataractispora (89%).
The 50% majority consensus tree inferred in the Bayesian analysis differed from the one MPT derived in parsimony analysis in the topology of the sampled orders and families of perithecial ascomycetes (FIG. 2). Two major lineages were discerned, the Xylariales (100 pP) and a lineage (100 pP) containing the rest of the investigated taxa forming six ingroup clades. Calosphaeria barbirostris clustered (92 pP) with Aquaticola/Cataractispora (95 pP) near the bottom of a large clade containing taxa with known holoblastic-denticulate conidiogenesis. This clade formed four additional subclades (viz. Cryptadelphia spp. [100 pP]; Rhamphoria delicatula Niessl, Xylomelasma sordida Réblová and Ceratostomella pyrenaica Réblová & Fournier [99 pP]; Lentomitella spp. [83 pP] and a subclade (72 pP) containing the Annulatascaceae (100 pP) being a sister of the Ophiostomatales (100 pP).
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TAXONOMY |
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Perithecia circinatim vel seriatim aggregata vel solitaria, non stromatica, fusca usque atra, venter globosus vel subglobosus, submersus; ostiolum e substrato protrudens, elongatum, subincurvum, totum pubescens, ostiolum periphysatum. Paries perithecii coriaceus vel fragilis, bistratosus; stratum externum e cellulis brunneis, textura prismatica, collum versus textura porrecta compositum; stratum internum e cellulis tenuitunicatis, subhyalinis vel hyalinis, elongatis compressis compositum. Paraphyses septatae, hyalinae, sursum angustatae, ascos superantes. Asci unitunicati, clavati, 8-spori. Ascosporae ellipsoideae, hyalinae, 1-septatae. Anamorphe Ramichloridium et Sporothrix similis.
Typus.. Barbatosphaeria barbirostris (Dufour : Fr.) Réblová
Etymology:. Latin Barbatus = bearded, refers to the conspicuous pubescence covering neck and perithecia.
Barbatosphaeria barbirostris (Dufour : Fr.) Réblová, comb. nov. FIGS. 3, 4
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= Ceratostomella barbirostris (Dufour : Fr.) Sacc., Syll. Fung. 1:410. 1882.
= Calosphaeria barbirostris (Dufour : Fr.) Ellis & Everh., North Amer. Pyrenom., p 512. 1892.
= Lentomitella barbirostris (Dufour : Fr.) Höhn., Sitzungsber. Kaiserl. Akad. Wiss., Math-Naturwiss. Kl., Abt. 1, 117:1022.1908.
Sphaeria scabriseta Schwein., Trans. Amer. Philos. Soc. 4:203. 1832.
= Eutypa scabriseta (Schwein.) Berk. & M.A. Curtis, Grevillea 4:97. 1876.
= Calosphaeria scabriseta (Schwein.) Sacc., Syll. Fung. 1:100. 1882.
Ceratostoma dispersum P. Karst., Mycol. Fenn. 2: 116. 1873.
= Ceratostomella dispersa (P. Karst.) Sacc., Syll. Fung. 1: 411. 1882.
Valsa lasiostoma Ellis & Everh., Bull. Torrey Bot. Club. 10:89. 1883.
= Enzigostoma lasiostomum (Ellis & Everh.) Kuntz, Revis. Gen. Pl. 3:474. 1892.
Anamorphs.. Ramichloridium and Sporothrix type.
Perithecia nonstromatic, dark brown to black, growing between periderm and wood, sometimes associated with old stromata of other pyrenomycetes, occasionally solitary, usually aggregated in short rows or in circular groups of 10–22 or in large loosening circular to oval nests of up to 30–40 perithecia. When in circular groups, necks are decumbent to perpendicular, converging, piercing the periderm in a group but never united in a disk. Venter globose to subglobose, 450–550 µm high, 350–500 µm diam, slightly roughened, with cylindrical, straight to slightly flexuous neck 500–1350 µm long, 110–150 µm wide. When young both venter and neck are sparsely covered with an olive to reddish brown pubescence that disappears with age, only the necks remaining covered with hairs over the whole length except the bare, black tips; hairs 2–6-septate, slightly constricted at the septa, smooth-walled, obtuse at the top, 4–5 µm wide, 35–100 µm long. Perithecial wall leathery to fragile, two-layered, 45–53 µm wide. Outer layer textura prismatica, cells brown polyhedral with wide lumina that tend to be longer toward the interior and becoming smaller outward; cells in the neck of textura porrecta. Inner layer of textura prismatica; cells hyaline, thin-walled and elongated. Ostiolum periphysate. Paraphyses abundant, persistent, septate, wider near the base ca. 4–6 µm, tapering to 2–3 µm toward the tip, longer than the asci. Asci unitunicate, clavate in sporiferous part, tapering toward the stipe, 39–47 x (5–)6–6.5 µm (broadest part), 25–35 µm long in pars sporifera, (mean ± SE = 45.15 ± 0.72 x 5.98 ± 0.1 µm; 31.89 ± 0.54 µm long in pars sporifera); broadly rounded to obtuse at the top, ascal apex nonamyloid with a shallow, refractive apical annulus 0.5–1 µm wide, ca. 2 µm high; 8-spored. Asci arising in croziers on elongating ascogenous hyphae, floating freely in centrum at maturity; basal part of the stipe conspicuously swollen, often remaining attached to the ascogenous hyphae after the mature ascus is released. Ascospores oblong to ellipsoidal, (5–)6–7 x 1.5–2 µm (mean ± SE = 6.32 ± 0.12 x 1.94 ± 0.04 µm), hyaline, smooth, 1-septate, non- or slightly constricted at the median septum, arranged obliquely 1- or 2-seriately in the upper sporiferous part of the ascus.
Characteristics in culture.— – Colonies slow growing, 1.3–1.8 cm diam on PCA after 21 d at 25C. Aerial mycelium whitish to beige, velvety, paler at the center, zonate and becoming darker toward the margin of the colony. Sporulation moderately dense in the center of the colony, becoming widespread with a uniform layer of conidiophores. Conidial masses whitish. Conidiophores of the Sporothrix type developing early from germinating ascospores and from young aerial mycelium, 4–5 x 1–1.5 µm, micronematous to semi-macronematous, unbranched or branched, flask-shaped to cylindrical or of irregular shape, hyaline, denticulate; conidiogenous cells polyblastic, integrated, terminal bearing 2–7 denticles producing conidia holoblastically; conidia 3.5–4 x 1–1.5 µm, 1-celled, hyaline, ellipsoid to suballantoid, curved, obtuse at the base. Conidiophores of the Ramichloridium type developing in 21 d or later on PCA, starting on the inoculum block, later widespread throughout the colony, 22–120 x 3–4 µm, macronematous, erect, simple, brown, septate, paler and thinner-walled toward the apex; conidiogenous cell polyblastic, 6–11 x 1.5 µm, integrated, terminal, cylindrical, tapering with rachis appearing much narrower than the basal part, proliferating sympodially bearing densely crowded inconspicuous denticles, on which the conidia are formed. Conidia 5–6 x 1–1.5 µm, 1-celled, hyaline, ellipsoidal, straight or curved, slightly obtuse at the base. Chlamydospores not observed.
Culture:. CBS 121149 ex J.F. 04053.
Specimens examined:.
CZECH REPUBLIC. Southern Bohemia: 
umava Mountains National Park, Prá
ily, 
danidla Mountain, decayed bark of a trunk of Fagus sylvatica, 20 Jun 1995, leg. M. Réblová M.R. 649 (PRA); ibid. umava National Park, glacial cirque of 
erné jezero Lake near elezná Ruda, decayed wood of F. sylvatica, 27 Aug 1998, leg. M. Réblová M.R. 1386 (PRA), ibid. umava Mountains National Park, Povyd
í, e
kova Pila, decayed bark of Ulmus glabra, 27 Aug 2000, Leg. M. Réblová 2887 (PRA); ibid. umava Mountains National Park, Mount Spálenit
near Sto
ec, decayed bark of a deciduous tree, 25 Aug 2001, leg. M. Réblová M.R. 2888 (PRA); Central Bohemia, Mount Vrchová near Nové Straecí, decayed branch of F. sylvatica, 25 Aug 19995, leg. M. Réblová M.R. 698 (PRA). FINLAND. Mustiala, inner side of the decayed bark of Betula, Nov., leg. P. Karsten (UPS, HOLOTYPE of Ceratostoma dispersum). FRANCE. Pyrénées Atlantiques, Ariège, Rimont, ruisseau de Peyran, decayed wood of Quercus robur, 24 Jun 2004, leg. F. Fournier J.F. 04053 (PRA). ITALY. On decayed wood, leg. L. Dufour (UPS [F-004917] 59201 HOLOTYPE of Sphaeria barbirostris; Fries’s herbarium, collection No. 540). USA. New Jersey. Newfield. On decaying branch of Q. alba, leg. J. Ellis & E. Everhart, North American Fungi Exsicc. No. 2122, Jan 1889 (K 122389 SYNTYPE of Valsa lasiostoma); ibid. Bethlehem. On decaying wood, 1914, leg. L.D. Schweinitz (K 122388 HOLOTYPE of Sphaeria scabriseta).
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DISCUSSION |
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, Vijaykrishna et al 2004).
Similarities in the teleomorph morphology have led to the incorrect placement of B. barbirostris in Calosphaeria. Perithecia of B. barbirostris occur between periderm and wood and they vary considerably in their disposition. They can occur either solitarily or in small circular groups with densely aggregated perithecia (FIG. 3a) or as large loosening circular to oval nests (FIG. 3b). Small circular groups occur directly on the wood or on old stromata of other pyrenomycetes beneath the periderm (e.g. some Diatrypales). In several collections perithecia were arranged in short dense rows (FIG. 3c), usually in fissures in the periderm. The distinct macroscopic feature of B. barbirostris is the clothing of the neck and the perithecium. Hairs cover the venter at early stages of development and for a short period at maturity, disappearing with age, leaving the surface glabrous or with sparse hairs, and only the neck bears conspicuous pubescence except the dark, obtuse tip.
The link between Ramichloridium and Sporothrix conidiophore types and B. barbirostris was established in vitro in this study. The different types of conidia of B. barbirostris described by Höhnel (1908), Munk (1957) or Barr (1985) could be formed by segmentation of the hairs that densely cover the neck. However such segmentation was not observed on recently collected material.
The organization of asci on ascogenous hyphae, croziers and paraphyses of B. barbirostris resemble those of C. faginea and members of the Diatrypales (i.e. Diatrypaceae, Graphostromataceae) as was documented by Samuels and Candoussau (1996). However in these other fungi the asci develop sequentially (i.e. the ascogenous system branches, producing croziers and ultimately asci at successively higher levels on each branch). A similar branching system also was described for species of Ceratostomella (Réblová 2006). In B. barbirostris the ascogenous hyphae elongate through proliferation and formation of croziers; they branch only rarely and do not produce any system of higher level branches.
Barbatosphaeria barbirostris can be compared with several phenotypically related taxa (e.g. Aquaticola, Lentomitella and Calosphaeria faginea [or C. dryina]) especially because of similarity in the ascospore morphology and the long-necked perithecia, which form circular formations in the two later taxa.
Two types of conidiophores, the Ramichloridium and the Sporothrix type, were observed to form in vitro during maturation of the colony of C. fagi (Samuels and Candoussau 1996) and B. barbirostris (the life history of C. dryina is not yet known). Despite the similar observations in conidiophore development, C. faginea can be distinguished clearly from B. barbirostris by its allantoid ascospores, sequential development of asci on branching ascogenous hyphae and lack of visible discharge mechanism in the ascal apex.
Although both Lentomitella and Barbatosphaeria share holoblastic-denticulate conidiogenesis, similar ascospore and partly perithecial characteristics, the LSU analyses clearly reject such a relationship. In the heuristic search Lentomitella is shown as more closely related to the species of the Magnaporthaceae and the Sordariales/Chaetosphaeriales/Boliniales group. The 50% majority consensus tree inferred from Bayesian analysis showed a large clade of taxa with dark, nonstromatic, long-necked perithecia, hyaline or pigmented ascospores with holoblastic-denticulate conidiogenesis, which contained the Lentomitella spp. (59%) clade and five additional clades (viz. Aquaticola/Cataractispora [89%] including B. barbirostris as a sister, the Annulatascaceae [66%], Cryptadelphia spp. [100%], the Ophiostomatales [98%] and the Ceratostomella/Xylomelasma/Rhamphoria clade. Lentomitella can be distinguished from B. barbirostris by somewhat robust ellipsoidal ascospores, short-stipitate cylindrical asci that do not float in the centrum at maturity and its occurrence on soft decayed decorticated wood.
In the present phylogenies the closest species to B. barbirostris were the terrestrial Cryptadelphia in Bayesian analysis and the freshwater genera Aquaticola and Cataractispora in both maximum parsimony and Bayesian analyses. Although in the maximum parsimony analysis there was no bootstrap support for grouping of B. barbirostris, Aquaticola and Cataractispora, in Bayesian analysis the value of posterior probabilities of this grouping was estimated as 92. Cryptadelphia is clearly distinguishable from B. barbirostris by its papillate perithecia, cylindrical asci with 1–2-seriately arranged 0–1-septate, ellipsoidal to ellipsoidal-fusiform ascospores and a Brachysporium anamorph. Aquaticola (Ho et al 1999) species differ from B. barbirostris by freshwater habitat, cylindrical asci, large apical annulus and ascospores with mucilaginous sheaths. Cataractispora (Hyde et al 1999) is another freshwater fungus shown as a close relative to both Aquaticola and B. barbirostris. Cataractispora differs from B. barbirostris by hyaline, long fusiform, several septate ascospores with apical appendages arranged 1-seriately in the ascus, presence of large apical annulus and freshwater habitat. The anamorphs of both Aquaticola and Cataractispora are unknown.
The new genus Barbatosphaeria is described to accommodate terrestrial ascomycetes with dark, long-necked, nonstromatic perithecia that can contain distinct clothing; short-ellipsoidal to oblong, septate, hyaline ascospores; asci arising from croziers on proliferating ascogenous hyphae without high-level branching system and with a shallow apical ring in the ascal apex. Assigning the appropriate order and family rank for Barbatosphaeria presents some difficulties; the genus grouped with Aquaticola and Cataractispora that until recently were considered core genera of the freshwater family Annulatascaceae. The remaining genera of the Annulatascaceae that were sampled (viz. Annulatascus, Annulusmagnus and Anidoptera) grouped together in all analyses, clearly separated from Aquaticola and Cataractispora; in Bayesian analysis they formed a monophyletic clade (100 pP) and in maximum parsimony they formed a clade (66% bootstrap support) with the terrestrial Rhamphoria delicatula on a basal branch. Because the phylogenetic affinity of the Trichosphaeriaceae has not been successfully established due to the lack of molecular and cultivation data no other family of unitunicate perithecial ascomycetes is available as a possible placement for Barbatosphaeria. Until this family matter can be addressed B. barbirostris is kept in an incertae sedis position. With an emphasis on the specific teleomorph morphology but similarity in anamorph development, B. barbirostris on one hand and C. faginea together with C. dryina and C. parasitica (pers obs of perithecial, ascal and ascospore characteristics) on the other hand might represent two closely related lineages of the derived calosphaeriaceous fungi with holoblastic conidiogenesis. Unfortunately the culture of C. faginea is no longer available (G. Samuels pers comm) and no recent material was available for molecular studies to confirm its affinity.
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ACKNOWLEDGMENTS |
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FOOTNOTES |
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1 E-mail: reblova{at}ibot.cas.cz
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LITERATURE CITED |
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50% from 1000 replicates are included at the nodes. Thickened branches indicate bootstrap support of 100%. Branch lengths are drawn to scale.
