(Hyphomycetes, Anamorphic fungi) from Cuba. Article (PDF Hongos anamórﬁcos / Cuba / hifomicetes / taxonomía. INTRODUCTION. PDF | Se registran por primera vez para México y se describen 10 especies de Hyphomycetes asociadas a restos vegetales, colectadas en diversas zonas. De líquenes se reportan especies (Breuss, ) y especies de hongos hyphomycetes (Delgado, ). A nivel de Centroamérica este grupo no ha.
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The diversity of aquatic Hyphomycetes in South America. Aquatic Hyphomycetes, also named Ingoldian or freshwater fungi, constitute a group of anamorphic fungi that are typically aquatic, producing tetraradiate, sigmoid or spherical conidia on submerged plant hoongos leaf litter, petioles, bark, etc. Mainly occurring in lotic systems, these fungi are considered to be one of the most active groups of organisms in the decomposition of leaf litter, and play a crucial role in the trophic chain.
Almost all studies are taxonomical, some with proper drawings and complete descriptions, but no keys have been provided yet, nor there is a specific culture collection for preserved strains. The published papers are still sporadic and dispersed, emphasizing a great need to improve the knowledge of the diversity of South American aquatic Hyphomycetes. The present review contents the check list of reported species until now, and has the aim to encourage the research concerned with aquatic Hyphomycetes in non explored regions of the continent.
The group of the aquatic Hyphomycetes comprises fungi that produce hyphomycstes exclusively in the aquatic environment or in the interstitial water among soil particles. Their habitats are preferencially streams with clear, clean, well-aerated waters, with moderate turbulence, and also reservoirs and lakes with different kinds or levels of pollution. The conidia may be trapped in foam, dispersed in the water, floating on the water surface or are associated to organic decomposing substrates as leaf litter and twigs From the taxonomical point of view, the aquatic Hyphomycetes constitute an artificial phylogenetically heterogenous group, being anamorphs of Ascomycota and Basidiomycota 1, Identification of the species has been mainly based on the morphological features of the conidia 40, The term “tetraradiate fungi”has been also frequently used to name this fungal group because many species produce conidia with a radiate or star-like shape, build by a central part, from which three or four arms are projected in divergent positions 18, The hydrodynamic shapes of the conidia confers to these fungi higher ability to remain suspended in the water for extended periods of time and improve the chances of the propagules to become attached to organic substrates, available for colonization.
However, among the aquatic Hyphomycetes hyhpomycetes are species that produces sigmoid, fusiform, coiled and spherical conidia too, which are also dependent of hyphomycetss aquatic environment to complete their life cycle 22, This fungal group has been also named “Ingoldian fungi”in honour to Prof. Ingold, who was one of the most important pioneers in the study of aquatic Hyphomycetes The eminent Professor studied these fungi in several aquatic environments in the United Hyyphomycetes and other countries starting from 40’s, describing species that are now considered cosmopolitan 36, According to their form and life-cycle, a classification of the freshwater fungi 22 into the following groups was proposed: Ingoldian Hyphomycetes fungi that present conidia with hydrodynamic shape and are exclusively dependent on aquatic environment for reproduction ; aero-aquatic Hyphomycetes fungi that may support submerged conditions but reproduce out of aquatic environmentsand terrestrial-aquatic Hyphomycetes and submerged-aquatic Hyphomycetes, which are observed in aquatic and terrestrial environments as facultative organisms.
One year later three groups were better distinguished among the former: Ingoldian fungi, aero-aquatic fungi and lignicolous aquatic fungi In the present revision representants of all these group were considered.
Hongos hyphomycetes de áreas tropicales y semitropicales del Estado de Veracruz
In such conditions, it can be difficult to distinguish aquatic from terrestrial hyphomycetee only on basis of the habitat. It has been observed that some typical geofungi isolated from such areas, like Epicoccum nigrum Link and Trichoderma viride Rifai are able to produce spores in submerged cultures Hongoos, Camposporium, Chaetendophragmia, Cladosporium, Cryptophiale, Dactylella, Dictyochaeta, Kionochaeta, Phaeoisaria, Subulispora, Tetraploa and other well-known terrestrial genera of Hyphomycetes are usually found on submerged litter as “facultative aquatic fungi” On the other hand, some typical aquatic species such as Sporidesmium and Articulispora has been isolated from non aquatic environments.
Fact is that, besides of the polemic discussion about which fungi are truly aquatic and if the terrestrial fungi may keep their saprophytic hability even in submerged conditions, the recognition of the importance of the aquatic Hyphomycetes has been continuously increased since many years. These fungi are considered predominant in the leaf decomposition process in aquatic environments. There is an evidence that aquatic Hyphomycetes are able to degrade several plant cell polymers such as cellulose, hemicellulose, pectin 16 and probably lignin honfosproducing amylase, cellulase, pectinase, protease, pyrocatechol oxidase, triacyl glycerol lipase and xylanase 17,40, Such degradative enzymes may cause breakdown of leaf tissues and increase the palatability to leaf-eating invertebrates, besides their biomass is an important component in the diet of aquatic invertebrates 9,18,57, Some aquatic fungi are able to degrade animal parts like insect hyphimycetes, hair and fish scales During the autumn in temperate climates, streams receive a great supply of tree leaves which may be densily colonize by a high diversity of aquatic Hyphomycetes 9.
In the tropics the richness of these fungi is probably influenced by the type of substrates, chemical and physical changes in the streams 35 as well as due complex interactions among several climatic and limnological factors 9, Thus, it has been considered that in the tropics, the analysis of the seasonal behavior of these fungi may be more difficult Based on accumulative results of several worldwide studies, about anamorphic genera and species of aquatic Hyphomycetes are known until now In the revision for tropical freshwater Hyphomycetes Goh 21 listed 19 taxa to South America without specifying the countries.
The quantification of the taxa in revisions hyphomycetfs with fungal diversity in the tropics may result different numbers in function of several definitions of aquatic fungi and also depends on the availability of the literature. There may be many interesting additional data in regional journals, monographs, thesis and reports.
As the aquatic Hyphomycetes has been characterized as one of the most active fungi in the mineralization of leaf litter, and consequently important dynamizers of the nutrient cycling in the aquatic environments, it has been considered relevant to increase the knowledge of the species diversity in terms of geographic distribution.
The aim of hyphommycetes revision is to present the state of the art of the studies concerned with aquatic Hyphomycetes in Brazil, in the context of South America, to encourage the conduction of surveys in unexplored areas of the continent. In Argentina the sampling of submerged mixed leaf litter, leaves of definied species such as Salix sp.
Dead leaves of Nothofagus dombeyi Mirb. Campylospora chaetocladia Ranzoni, Clathrosphaerina zalewskii v.
The diversity of aquatic Hyphomycetes in South America
Among the mycota associated with grass leaves, dicotyledoan leaf litter, wood and foam samples, 12 aquatic Hyphomycetes were reported in some streams and lakes in Tierra del Fuego Surveys were performed in the subtropical region of Santiago River in Buenos Aires 5,6,7resulting in the description of 19 Hyphomycetes including nine new species and one new combination, Dictyochaeta assamica Agnihothrudu Arambarri, Cabello and Mengascini.
Furthering the studies with Hyphomycetes from Santiago River, Cabello et al. The taxonomical descriptions are complete and well documented by drawings. Besides, several other studies were performed at several localities in Argentina, involving the sampling of leaf litter or woody debris, from which many not typical aquatic fungi were isolated 3,4,11,12, In Hkngos Table hyphomucetessamples of wood, leaf litter and insects were collected in several streams and lakes in the temperate region of Osorno The authors observed 14 taxa of Ingoldian fungi, identified nine at specific level and documented their taxonomic features by spore drawings.
Matsushima 41,42 greatly contributed to the knowledge of Hyphomycetes in South America.
Several decaying palmae petioles mainly but also leaf litter, fruits and soil samples were collected in the vicinity of some rivers in the equatorial Amazon region of Ecuador and Peru. In Ecuador Table 1 5 species were reported Many fungi with star-like conidia or considered aquatic were isolated but it is not clear if they were obtained from really submerged substrates.
In Peru 30 taxa were described The Hyphomycetes were fully described and documented through excellent photographs and drawings. In Venezuela Table 1 11 taxa of aquatic Hyphomycetes were isolated from submerged leaf litter, branches and petioles of Casuarina in streams, pools and waterfalls in the surroundings of Caracas Thus, some species were observed during fungal decomposition of leaves of Ficus microcarpa L.
Later, aquatic Hyphomycetes were observed during the decomposition of leaves of Quercus robur L. Sutton were observed during the decomposition of leaves of Cedrela fissilis Vell. On the same plant species, but in the reservation of “Horto Florestal Dr. Kirk was reported At the surface of the leaves of Alchornea triplinervia Spreng.
Hughes and Subulispora procurvata Tubaki were observed In the same region, the mycota associated with leaves of Ficus microcarpaAlchornea triplinervia and Quercus robur were compared, evaluating the diversity 53the methods for fungal quantification to express the colonization intensity 45 and the correlation between fungal diversity zoosporic fungi and aquatic Hyphomycetes and macro and microelements during the decomposition 54, In the same Reserve, Dendrosporomyces splendens Nawawi Nawawi, a typical species from water, was isolated from Alchornea triplinervia and Euterpe edulis Mart.
More recently 9 taxa were isolated from decomposing leaves of Miconia cabussu On Tibouchina pulchra leaves six Hyphomycetes were observed on leaves 31 and 11 were involved in the fungal succession during the decomposition of submerged leaf litter Recently, a taxonomical revision of some species of Subulispora S. Although the number of taxa and studies are higher in Brazil than in other South American countries, no new species have been described until now.
Also the quality of the taxonomical descriptions and drawings must be improved. The Brazilian Amazonian region, where water bodies are plenty is still almost unknown. Only 1 record, Helicosporium sp. Comparing the results among the countries, one may observe that some species such as Anguillospora longissima Sacc.
Since in many countries no data about this fungal group have been published, and the studies are very scarce, sporadic and dispersed, it is difficult to draw conclusions about the geographic distribution of aquatic Hyphomycetes in South America. In Brazil, as well as probably in other countries of South America, the interest of researchers and students in the taxonomy of aquatic Hyphomycetes has come from the observation of the species in ecological studies about leaf litter decomposition and fungal succession.
However, the scarcity of taxonomical keys with tropical species and the difficulty of obtaining cultures on agar media has disencouraged further initiatives. So, the publication of keys and the improvement of the isolation techniques of these fungi in tropical waters may stimulate the interest of more taxonomists in the systematics and ecology of aquatic Hyphomycetes.
Considering the dimension of the Continent, with the high variability of vegetation, habitats and abundance of rivers, streams and waterfalls, the number of aquatic Hyphomycetes in South America, around 90, is still very low. More effort is needed in terms of surveys and taxonomical studies to improve the knowledge of these fungi.
Hongos hyphomycetes de los municipios centrales del estado de Veracruz
The author would like to thank to CNPq for financial support and Prof. Micoflora de la hojarasca de Nothofagus pumilio. Darwiniana25 Dictyosporium triramosuma new Hyphomycete from Argentina. Estudio sistematico de los Hyphomycetes del Rio Santiago prov. Darwiniana28 Buenos Aires Province, Argentina. Research on aquatic Hyphomycetes: The ecology of aquatic Hyphomycetes. Springer Verlag, Berlin,p. Hongos saprobios en Chile: Minimidochium parvuma new species of hyphomycete from Argentina.
New Hyphomycetes from Santiago River. Estudio sistematico de los Hyphomycetes del Rio Santiago. Cell-wall degrading enzymes of aquatic Hyphomycetes: Honyos of extra-cellular cellulase by Lunulospora curvula and Flagellospora penicillioides.
Micoflora de la hojarasca de Nothofagus dombeyi. Darwiniana21 1: Hifomicetes Deuteromycotina acuaticos de Tierra del Fuego.