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Some freshwater ascomycetes from Mexico
Abstract
As part of a study of freshwater ascomycetes occurring on submerged Pinus sp. wood panels in two canals of Xochimilco, Mexico, Ascotaiwania lignicola, Jahnula poonythii, Ophioceras commune and Savoryella lignicola are reported from this country for the first time. Notes on the morphological characteristics of these species are given, including illustrations.
... Most species of Jahnula described subsequently, however, have been reported from the Old World throughout the Asian and Australian tropics (Hyde 1993, Hyde and Wong 1999, Pang et al 2002, Pinruan et al 2002. One exception is J. poonythii K.D. Hyde and S.W. Wong, a species that originally was described and reported from Mauritius (Hyde and Wong 1999) and recently reported by Gonzalez and Chavarria (2005) from a freshwater source in Mexico. In this paper we describe and illustrate three new species and report and describe four additional species of Jahnula for the first time from the western hemisphere. ...
... 57,60). This feature has not been reported for the type species by Hyde and Wong (1999) or by Gonzalez and Chavarria (2005), who reported J. poonythii from Mexico. Jahnula seychellensis K.D. Hyde and S.W. Wong, Nov Hedwig 68:504. ...
... the western hemisphere. An additional species, J. poonythii K.D. Hyde and S.W. Wong, also was reported from Mexico (Gonzalez and Chavarria 2005). These reports indicate that the genus is more widely distributed longitudinally than previously thought. ...
Three new species of loculoascomycetes collected from freshwater habitats in North America are described as new species of Jahnula (Jahnulales, Dothideomycetes). All three share these morphological features: hyaline to blackish translucent, membranous ascomata with subtending, wide, septate brown, spreading hyphae; peridia composed of large angular cells; hamathecium of septate pseudoparaphyses; 8-spored, clavate to cylindrical asci; and 1-septate, broadly fusiform, brown, multiguttulate ascospores. Four additional species, J. aquatica, J. bipolaris, J. potamophila, and J. seychellensis, are reported for the first time from the western hemisphere.
... In Mexico, an important effort to explore fungal diversity has been made (Guzmán, 1998). Exploration of aquatic fungal diversity has also been conducted by traditional methods isolating fungi from freshwater and marine environments (González & Chavarría, 2005;González, Hanlin, Herrera, & Ulloa, 2000;González, Hanlin, & Ulloa, 2001; Heredia, Reyes, Arias, Mena-Portales, & Mercado Sierra, 2004). ...
With the aim to explore the diversity of aquatic fungi in Mexico we present an investigation using a fragment of the 18S ribosomal DNA as a molecular marker obtained from different water bodies (marine, brackish and fresh water). Ribosomal gene fragments were obtained by DNA amplification, the resulting sequences were compared using multiple alignments against a collection of classified reference fungal sequences and then subjected to phylogenetic clustering allowing the identification and classification of DNA sequences from environmental isolates as fungal down to the family level, provided enough reference sequence were available. From our ensemble of 2,020 sequences identified as fungal, 23.8% were classified at the family level, 48.5% at the order level, 13% at the class/subphylum level and 14.7% of the sequences (all from the same site) could not be unambiguously positioned in any of our reference fungal groups but were closely related to uncultivated marine fungi. The most frequently recovered phylum was Ascomycota (89.1%), followed by Chytridiomycota (8.1%), Basidiomycota (2.8%) and Mucoromycotina (1.3%).
... In Mexico, an important effort to explore fungal diversity has been made (Guzmán, 1998). Exploration of aquatic fungal diversity has also been conducted by traditional methods isolating fungi from freshwater and marine environments (González & Chavarría, 2005;González, Hanlin, Herrera, & Ulloa, 2000;González, Hanlin, & Ulloa, 2001; Heredia, Reyes, Arias, Mena-Portales, & Mercado Sierra, 2004). ...
... Little is known about the biodiversity of this group of ascomycetes from tropical eco-regions () and particularly Mexico. The only knowledge of ascomycetes from a lentic freshwater environment is from a study by González & Chavarria (2005) of freshwater ascomycetes from a temperate urban ecosystem situated in the metropolitan zone of Mexico City. During the past two years a biodiversity project to study lignicolous freshwater ascomycetes of the State of Tabasco was undertaken because it is located in one of the highest precipitation regions of Mexico, which results in an elevated diversity of natural and urban lentic habitats. ...
A survey of lignicolous freshwater ascomycetes was carried out in Las Ilusiones Lagoon located in the metropolitan area of Villahermosa City, State of Tabasco, Mexico. Aniptodera inflatiascigera, Ascosacculus aquaticus and A. heteroguttulatus are recorded for the first time from Mexico. This study is an important contribution to the knowledge of the worldwide distribution of these three species from tropical freshwater ecosystems.
... Ophioceras commune es una especie dulceacuícola de amplia distribución. Crece sobre madera sumergida en Panamá, Hong Kong, China, Japón, Estados Unidos y México (Shearer et al., 1999;Tsui et al., 2001;Cai et al., 2002;González y Chavarria, 2005). En la temporada de lluvias se encuentra abundantemente en Xochimilco en bloques de madera de pino. ...
The diversity of freshwater Ascomycetes was determined in the touristic channel Santa Cruz, Xochimilco, Mexico. Two surveys were conducted in 2007 during the dry and wet season. Four sampling sites were selected in the channel margin, based on the level of urbanization. At each sampling site, wood panels of Tabebuia donnell-smithii, Bucida buceras, Pinus sp., Cupressus lindlei and Abies religiosa were submerged during 8 weeks. Water temperature, dissolved oxygen, organic matter, phosphorus and most probable number of coliform bacteria were determined. Results were evaluated using the diversity index of Shannon and the index of similarity of Sørensen. The highest Ascomycete diversity recorded (H' = 1.152) was found at the third sampling site, located near commercial florist greenhouses. The lowest diversity (H' = 0.976) was obtained at the first sampling site, in front of Santa Cruz pier. Both values of diversity were in agreement with the urbanization level and physicochemical and bacteriological data. The wet season had the lowest diversity of freshwater Ascomycetes, perhaps due to the effect of the rainfall in this aquatic environment.
... Ophioceras commune es una especie dulceacuícola de amplia distribución. Crece sobre madera sumergida en Panamá, Hong Kong, China, Japón, Estados Unidos y México (Shearer et al., 1999;Tsui et al., 2001;Cai et al., 2002;González y Chavarria, 2005). En la temporada de lluvias se encuentra abundantemente en Xochimilco en bloques de madera de pino. ...
Resumen. Se investigó la diversidad de los ascomicetes del canal Santa Cruz, considerado el de mayor importancia turística en Xochimilco, Distrito Federal. En 2007 se realizaron 2 muestreos en las épocas de menor y mayor precipitación. En el márgen del canal se establecieron 4 estaciones de muestreo con diferente grado de urbanización y en cada una se sumergieron bloques de madera de Virola sp., Tabebuia donnell-smithii, Bucida buceras, Pinus sp., Cupressus lindlei y Abies religiosa durante 8 semanas. Se midió la temperatura, el pH, el oxígeno disuelto, la materia orgánica y el fósforo, y se determinó el número más probable de bacterias coliformes del agua. Para evaluar los datos, se aplicaron el índice de diversidad de Shannon y el índice de similitud de Sørensen. La mayor diversidad de ascomicetes (H' = 1.152) se registró en la tercera estación, ubicada en la zona de viveros con flores y la menor diversidad (H' = 0.976) se obtuvo en la primera estación, localizada frente al embarcadero Santa Cruz, ambos valores de diversidad coincidieron con el grado de urbanización y con los datos fisicoquímicos y bacteriológicos. La temporada de lluvias presentó la diversidad más baja debido probablemente al efecto de la precipitación en este ambiente acuático. Palabras clave: ambiente léntico, bacterias coliformes, Ascomycetes dulceacuícolas, madera en sumersión, micología, taxonomía. Abstract. The diversity of freshwater Ascomycetes was determined in the touristic channel Santa Cruz, Xochimilco, Mexico. Two surveys were conducted in 2007 during the dry and wet season. Four sampling sites were selected in the channel margin, based on the level of urbanization. At each sampling site, wood panels of Tabebuia donnell-smithii, Bucida buceras, Pinus sp., Cupressus lindlei and Abies religiosa were submerged during 8 weeks. Water temperature, dissolved oxygen, organic matter, phosphorus and most probable number of coliform bacteria were determined. Results were evaluated using the diversity index of Shannon and the index of similarity of Sørensen. The highest Ascomycete diversity recorded (H' = 1.152) was found at the third sampling site, located near commercial florist greenhouses. The lowest diversity (H' = 0.976) was obtained at the first sampling site, in front of Santa Cruz pier. Both values of diversity were in agreement with the urbanization level and physicochemical and bacteriological data. The wet season had the lowest diversity of freshwater Ascomycetes, perhaps due to the effect of the rainfall in this aquatic environment.
... Ophioceras commune es una especie dulceacuícola de amplia distribución. Crece sobre madera sumergida en Panamá, Hong Kong, China, Japón, Estados Unidos y México (Shearer et al., 1999;Tsui et al., 2001;Cai et al., 2002;González y Chavarria, 2005). En la temporada de lluvias se encuentra abundantemente en Xochimilco en bloques de madera de pino. ...
The diversity of freshwater Ascomycetes was determined in the touristic channel Santa Cruz, Xochimilco, Mexico. Two surveys were conducted in 2007 during the dry and wet season. Four sampling sites were selected in the channel margin, based on the level of urbanization. At each sampling site, wood panels of Tabebuia donnellsmithii, Bucida buceras, Pinus sp., Cupressus lindlei and Abies religiosa were submerged during 8 weeks. Water temperature, dissolved oxygen, organic matter, phosphorus and most probable number of coliform bacteria were determined. Results were evaluated using the diversity index of Shannon and the index of similarity of Sørensen. The highest Ascomycete diversity recorded (H' = 1.152) was found at the third sampling site, located near commercial florist greenhouses. The lowest diversity (H' = 0.976) was obtained at the first sampling site, in front of Santa Cruz pier. Both values of diversity were in agreement with the urbanization level and physicochemical and bacteriological data. The wet season had the lowest diversity of freshwater Ascomycetes, perhaps due to the effect of the rainfall in this aquatic environment.
... Variation in habitat type is often known to affect the movement, settlement and community composition of plants and animals (Morin 1999), but the influence of habitat type on freshwater ascomycete community composition is unexplored and poorly understood. A number of studies on freshwater ascomycetes have been conducted at single, spatially limited sites that were either lentic (Shearer and Crane 1986;Hyde and Goh 1998a;Goh and Hyde 1999;Cai et al. 2002;Luo et al. 2004;see Wong et al. 1998) or lotic habitats (Lamore and Goos 1978;Shearer and Von Bodman 1983;Hyde et al. 1998;Hyde and Goh 1998b;Hyde and Goh 1999;Ho et al. 2002;Sivichai et al. 2000Sivichai et al. , 2002Tsui et al. 2001Tsui and Hyde 2004;Kane et al. 2002;Cai et al. 2003;Gonźalez and Chavarŕia 2005;see Wong et al. 1998). However, thus far, no studies have examined distribution of freshwater ascomycetes simultaneously in both lotic and lentic habitats to compare species composition between habitat types. ...
Freshwater ascomycetes are important decomposers of dead woody and herbaceous debris in aquatic habitats. Despite evidence of their ecological importance, latitudinal, habitat and substrate distributional patterns of freshwater ascomycetes are poorly understood. In this study, we examined the latitudinal and habitat distributional patterns, and substrate recurrences of freshwater ascomycetes by collecting dead submerged woody and herbaceous debris in lentic and lotic habitats at five selected sites along
a north-central-south, temperate–subtropical latitudinal ecotone in Florida. One hundred and thirty-two fungal taxa were collected during the study. Seventy-four were meiosporic and 56 were mitosporic ascomycetes, while two species were basidiomycetes. Canonical analyses of principal coordinates (CAP) and Sørenson’s similarity index of species based on presence/absence data revealed a high turnover in species composition between the northern and southern sites, indicating a change in species composition along the temperate–subtropical latitudinal ecotone of the Florida Peninsula. Results from the ordination analysis indicated that freshwater ascomycete community composition is not significantly different between lentic and lotic habitats in Florida. The geographically broadly distributed species and species commonly found in Florida occurred in both habitats, whereas a number of new or rare species occurred in either lentic or lotic habitats, but not both. The same freshwater ascomycete species
did not necessarily occur on both woody and herbaceous debris; of the 132 taxa collected, 100 were reported only on woody debris; 14 species occurred exclusively on herbaceous debris; and 18 species were found on both woody and herbaceous debris in lentic or lotic habitats. Implications of data from this study to the conservation and knowledge of biodiversity for freshwater ascomycetes is discussed.
Research into freshwater fungi has generated a wealth of information over the past decades with various published articles, i.e., reviews, books, and monographs. With the advancement of
methodologies used in freshwater fungal research, and numerous mycologists working on this ecological group, our knowledge progress and understanding of freshwater fungi, including novel
discoveries and new insights in the ecology of freshwater fungi, has advanced. With this enormous progress, it is timely that an updated account of freshwater fungi be compiled in one volume. Thus, this account is published to give a comprehensive overview of the different facets of freshwater fungal biology. It includes an updated classification scheme based on the latest taxonomic and phylogenetic analysis of freshwater fungal taxa, including their evolutionary history. The biology, diversity, and geographical distribution of higher and basal freshwater fungi are also discussed in the entries. A section on dispersal and adaptation of filamentous freshwater fungi is included in the present work. The ecological importance and role of fungi in the breakdown of wood in freshwater habitats, including their physiology, are discussed in detail. The biotechnological potential of freshwater fungi as producers of bioactive metabolites are reviewed, with methodologies in antimicrobial drug discovery. The present volume also provides an overview of different high throughput sequencing (HTS) platforms for freshwater fungal research highlighting their advantages and challenges, including recent studies of HTS in identification and quantification of fungal communities in freshwater habitats. The present volume also identifies the knowledge gaps and direction of future research in freshwater fungi.
A comprehensive account of fungal classification from freshwater habitats is outlined and discussed in the present review based on literature of biodiversity studies and recent morpho-phylogenetic analyses. A total of 3,870 freshwater fungal species are listed with additional details on the isolation source, habitat, geographical distribution, and molecular data. The Ascomycota (2,968 species, 1,018 genera) dominated the freshwater fungal taxa wherein Sordariomycetes (823 species, 298 genera) had the largest number, followed by Dothideomycetes (677 species, 229 genera), Eurotiomycetes (276 species, 49 genera), and Leotiomycetes (260 species, 83 genera). Other phyla included in the updated classification of freshwater fungi are: Chytridiomycota (333 species, 97 genera), Rozellomycota (221 species, 105 genera), Basidiomycota (218 species, 100 genera), Blastocladiomycota (47 species, 10 genera), Monoblepharomycota (29 species, 6 genera), Mucoromycota (19 species, 10 genera), Aphelidiomycota (15 species, 3 genera), Entomophthoromycota (6 species, 4 genera), Mortierellomycota (5 species, 3 genera), Olpidiomycota (4 species, 1 genus), Zoopagomycota (3 species, 2 genera), and Sanchytriomycota (2 species, 2 genera). The freshwater fungi belong to 1,361 genera, 386 families and 145 orders. The Pleosporales and Laboulbeniaceae are the largest freshwater fungal order and family comprised of 391 and 185 species, respectively. The most speciose genera are Chitonomyces (87, Laboulbeniomycetes), Verrucaria (50, Eurotiomycetes), Rhizophydium (52, Rhizophydiomycetes), Penicillium (47, Eurotiomycetes), and Candida (42, Saccharomycetes).
Freshwater Dothideomycetes are a highly diverse group of fungi, which are mostly saprobic in freshwater habitats worldwide. They are important decomposers of submerged woody debris and leaves in water. In this paper, we outline the genera of freshwater Dothideomycetes with notes and keys to species. Based on multigene analyses and morphology, we introduce nine new genera, viz . Aquimassariosphaeria , Aquatospora , Aquihelicascus , Fusiformiseptata , Neohelicascus , Neojahnula , Pseudojahnula , Purpureofaciens , Submersispora ; 33 new species, viz . Acrocalymma bipolare , Aquimassariosphaeria kunmingensis , Aquatospora cylindrica , Aquihelicascus songkhlaensis , A. yunnanensis , Ascagilis submersa , A. thailandensis , Bambusicola aquatica , Caryospora submersa , Dictyocheirospora thailandica , Fusiformiseptata crocea , Helicosporium thailandense , Hongkongmyces aquaticus , Lentistoma aquaticum , Lentithecium kunmingense , Lindgomyces aquaticus , Longipedicellata aquatica , Neohelicascus submersus , Neohelicomyces dehongensis , N. thailandicus , Neohelicosporium submersum , Nigrograna aquatica , Occultibambusa kunmingensis , Parabambusicola aquatica , Pseudoasteromassaria aquatica , Pseudoastrosphaeriella aquatica , Pseudoxylomyces aquaticus , Purpureofaciens aquatica , Roussoella aquatica , Shrungabeeja aquatica , Submersispora variabilis , Tetraploa puzheheiensis , T. yunnanensis ; 16 new combinations, viz. Aquimassariosphaeria typhicola , Aquihelicascus thalassioideus , Ascagilis guttulaspora , A. queenslandica , A. seychellensis , A. sunyatsenii , Ernakulamia xishuangbannaensis , Neohelicascus aquaticus , N. chiangraiensis , N. egyptiacus , N. elaterascus , N. gallicus , N. unilocularis , N. uniseptatus , Neojahnula australiensis , Pseudojahnula potamophila ; 17 new geographical and habitat records, viz. Aliquandostipite khaoyaiensis , Aquastroma magniostiolata , Caryospora aquatica , C. quercus , Dendryphiella vinosa , Ernakulamia cochinensis , Fissuroma neoaggregatum , Helicotruncatum palmigenum , Jahnula rostrata , Neoroussoella bambusae , N. leucaenae , Occultibambusa pustula , Paramonodictys solitarius , Pleopunctum pseudoellipsoideum , Pseudocapulatispora longiappendiculata , Seriascoma didymosporum , Shrungabeeja vadirajensis and ten new collections from China and Thailand, viz. Amniculicola guttulata , Aquaphila albicans , Berkleasmium latisporum , Clohesyomyces aquaticus , Dictyocheirospora rotunda , Flabellascoma fusiforme , Pseudoastrosphaeriella bambusae , Pseudoxylomyces elegans , Tubeufia aquatica and T. cylindrothecia . Dendryphiella phitsanulokensis and Tubeufia roseohelicospora are synonymized with D. vinosa and T. tectonae , respectively. Six orders, 43 families and 145 genera which belong to freshwater Dothideomycetes are reviewed. Of these, 46 genera occur exclusively in freshwater habitats. A world map illustrates the distribution of freshwater Dothideomycetes.
The number of extant freshwater fungi is rapidly increasing, and the published information of taxonomic data are scattered among different online journal archives. The only online repository, http://fungi.life.illinois.edu/, deals with freshwater ascomycetes and their asexual morphs. Other freshwater fungal groups are not included. The newly developed webpage (www.freshwaterfungi.org/) serves as a gateway to freshwater fungal systematics that provides comprehensive and updated information including detailed descriptions, photographic plates and illustrations, notes, phylogenetic trees, estimated and extant list of species, and other related information. The website is developed with user-friendly interfaces, and the usage is discussed in this paper.
Three new species of loculoascomycetes collected from freshwater habitats in North America are described as new species of Jahnula ( Jahnulales, Dothideomycetes). All three share these morphological features: hyaline to blackish translucent, membranous ascomata with subtending, wide, septate brown, spreading hyphae; peridia composed of large angular cells; hamathecium of septate pseudoparaphyses; 8-spored, clavate to cylindrical asci; and 1-septate, broadly fusiform, brown, multiguttulate ascospores. Four additional species, J. aquatica, J. bipolaris, J. potamophila, and J. seychellensis, are reported for the first time from the western hemisphere.
Freshwater ascomycetes are the predominant fungal colonizers of ligno-cellulosic substrates submerged in freshwater habitats. Although considered important decomposers and a food resource in freshwater food webs, little is known about the influence of environmental factors on their geographical distribution patterns, species richness and community structure. We undertook a study of the distribution of freshwater lignolytic ascomycetes in the Madre de Dios River basin in Peru along an elevational gradient from the headwater regions dominated by the Inambari and Araza Rivers to the lowlands of the Madre de Dios River. The gradient extended from 218 to 3870 m; collections were made at low (<300 m), medium (300–1000 m) and high (>1000 m) elevations. Three separate collecting trips were conducted during the dry seasons over 3 years. Samples of submerged woody debris were returned to the University of Illinois where they were incubated in moist chambers and examined for the presence of sexual and asexual reproductive structures, which were used for identification. GPS location, altitude, water temperature and pH were measured at the time of collection. A total of 2187 vouchered fungal collections representing 268 fungal taxa were collected. One hundred and fifty-nine taxa were collected at low elevations, 201 at middle elevations and 56 at high elevations. Only 33 of 268 taxa occurred at all three elevational ranges. Canonical analyses of principal coordinates and Sørensons Similarity Index of species based on presence/absence data revealed different structuring of freshwater fungal communities at low, middle, and high elevations, indicating a change in species composition along the Andes to Amazon elevation gradient. Mantel’s tests demonstrated that beta diversity is strongly impacted by both elevation and pH as rapid taxonomic turnover was associated with both these factors. Of 140 species found in their sexual reproductive state, only ten occurred at all three elevational ranges. The most commonly occurring species was Annulatascus velatisporus, a species with a worldwide distribution. Of 128 taxa found in their asexual reproductive state, 23 occurred at all three elevational ranges. The most commonly collected species was Candelabrum broccchiatum, also a species with a worldwide distribution. Most of the taxa reported from Peru have been reported previously from Asian and/or Australian freshwater tropical habitats. One hundred and three species are new records for South America and 137 species are new records for Peru. About 80 species found in Peru have a pan-tropical distribution. Whether these distribution patterns exist due to vicariance or geodispersal remains to be determined. This study indicates that the composition of fungal communities in mountainous areas is influenced by elevation and has implications for the effects of global warming.
Hyalorostratum brunneisporum gen. et sp. nov. (ascomycetes) is described from freshwater habitats
in Alaska and New Hampshire. The new genus is considered distinct based on morphological
studies and phylogenetic analyses of combined nuclear ribosomal (18S and 28S) sequence data.
Hyalorostratum brunneisporum is characterized by immersed to erumpent, pale to dark brown
perithecia with a hyaline, long, emergent, periphysate neck covered with a tomentum of hyaline,
irregularly shaped hyphae; numerous long, septate paraphyses; unitunicate, cylindrical asci with a
large apical ring covered at the apex with gelatinous material; and brown, one-septate ascospores
with or without a mucilaginous sheath. The new genus is placed basal within the order Diaporthales
based on combined 18S and 28S sequence data. It is compared to other morphologically similar
aquatic taxa and to taxa reported from freshwater habitats that share affinities to the Diaporthales.
Phycomycetes are found in nearly all kinds of freshwater habitats, in damp soil as well as in seawater. They occur as saprophytes or facultative parasites on dead insects, algae, twigs, seeds, dead leaves, and fruits. Phycomycetes rarely develop in sufficient numbers for them to be identified in the field, consequently baiting techniques have been developed for their detection and isolation from water and soil. Baiting techniques have been used successfully for many years. A great variety of substrates have been used as baits, for example, hard green apples, small pears, tomatoes, grapes, plums, rose hips, green bananas, sweet corn kernels, loquets, mangoes, cashews, and hawthorn berries. The materials used as bait should be placed in small quarter-inch galvanized wire mesh baskets or plastic-covered wire baskets. These baskets are suspended in the water by nylon rope for a suitable period, determined by withdrawing samples at intervals. Marine Ascomycetes are to be found growing on algae, leaves and culms of Angiosperms, rope, and timber. The most intensively investigated group of marine Ascomycetes is the lignicolous forms. These can be collected on cordage (rope nets, mooring lines and such) bits of submerged or drifting wood. Care must be exercised in looking at drift material, as the fungi present need not necessarily be marine. In choosing a testing site, a number of factors should be considered, for example, tidal race, exposed or sheltered shore, local contamination from land drains or sewage effluents, and sandy or stony sea bed. All these can markedly affect the colonization of wood blocks by marine fungi and other marine organisms.
Five scolecosporous pyrenomycetes collected from freshwater habitats are described as new species of Ophioceras. All five species share the following morphological character states: dark brown to black pigmented ascomata with long, periphysate beaks and peridia of textura angularis; long, tapered, septate paraphyses with apically free ends; unitunicate asci with a cylindrical, chitinoid apical apparatus; asci that separate from the hymenial layer (deciduous) and phragmoseptate, hyaline to lightly pigmented, scolecosporous ascospores. All of the new species and O. leptosporum form soft-rot cavities on wood. The genera Ophioceras and Pseudohalonectria are provisionally placed in the Magnaporthaceae. Ordinal placement remains uncertain.
Conservation of the vegetation, analysis of the knowledge of the diversity of fungi, new biological methods and estimates of the numbers of species of fungi that grow in Mexico are discussed. The great forest destruction that is occurring and the loss of fungal diversity in the country is seriously depleting total biodiversity, mainly in the tropics. Methods to establish the number of Mexican species of fungi are proposed based on an average of: (1) the numbers of fungal obligates of vascular plants and animals and of the saprobic species; (2) extrapolating the number of the British fungi to Mexico, taking the British mycota as the best known in the world; and (3) extrapolating to the country the number of species known to occur in the State of Veracruz (Mexico), the best known in the country. The average of these three calculations yields about 200 000 species of fungi for Mexico. Of these, only 3.5% are known, despite considerable progress having been made in the inventory of the country's fungi in the last 30 years. It is concluded that it is necessary to place more emphasis on alpha taxonomy, to train more specialists and to prepare monographs of several groups of fungi.
Three species are currently assigned to the genus Savoryella. All are re-examined and additional features recorded. Two new species S. appendiculata Hyde et Jones and S. longispora Jones et Hyde are described, from logs and driftwood collected from Malaysia and Brunei. The genus is assigned to the Sordariales.
The species ofSavoryella from freshwater are discussed and a key is provided.Savoryella grandispora sp. nov. from Malaysia is described and illustrated with interference contrast micrographs.
Driftwood, prop roots and other mangrove samples were collected from the intertidal regions of Brillant and Anse Boileau mangrove stands, in the Seychelles. This material was examined for the presence of higher marine fungi. Forty seven species of marine fungi were collected (37 Ascomycotina, 1 Basidiomycotina, 9 Deuteromycotina), with Halocypluna villosu the most common fungus, while Aniptodera mungrovii, Antennospora quudricorruita, Halosarpheia marina, Ascomyccte sp. (4), and Lulworthiu grandispora were collected frequently. The mycota of the two mangrove stands arc compared. A list of fungi recorded from mangroves is compiled.