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Copyright of Boletín de la Sociedad Argentina de Botánica is the property of Sociedad Argentina de Botanica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lilloa is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forest vegetation is key for buffering microclimatic factors and regulating atmospheric deposition. Epiphytic lichens are sensitive to these factors and can indicate the overall health status of the ecosystem. Specifically, the analysis of morpho-anatomical variations allows us to understand the degree of tolerance or sensitivity of these organisms exposed to agricultural crops and how vegetation might buffer this response. We analyzed variations in vegetative and reproductive characters and injuries in thalli of Parmotrema pilosum as a response to distance to crops and forest cover. The study was conducted in forest patches of the Espinal in central Argentina, an ecosystem threatened by agricultural activity. We selected 10 sites with different forest cover areas and two collection points differing in distance to crops: sites adjacent to (0 m) and far from (150 m) crops. We collected five thalli from each collection point and analyzed variations in morpho-anatomical characters at macro- and microscopic levels. We found a lower number of algae and a higher proportion of simple cilia in individuals at points adjacent to crops. At points with low forest cover, a thinner upper cortex was observed, whereas at points with greater forest cover, an increase of necrosis and greater presence of apothecia were detected. Bleaching was the most frequent injury at sites adjacent to crops, decreasing with increasing forest cover. Conservation and reforestation of Espinal forest patches would promote the propagation of lichens affected by agricultural practices. [ABSTRACT FROM AUTHOR]

Three genera and nineteen species of foliose Physciaceae from Buenos Aires Province are studied. Their common features are summarized and main morphological variability illustrated Generic descriptions are provided. Species are briefly described, commented and illustrated Problems related to the identification of some secondary products, the anatomy and histology of thalli and apothecia, and the vegetative propagules, as well as the corresponding terminology, are discussed The Importance of an adequate methodology for studying the thallus structure is stressed. Keys to genera and species have been published in an earlier paper (Bol. Soc. Argent. Bot. 28: 169-173, 1992). [ABSTRACT FROM AUTHOR]

A new species belonging to the Dothideomycete genus Acanthostigvna is described from bark of two Nothofagus species from Argentina. Its identity as a new species is based on both morphology and molecular sequence data. Acanthostigma patagonica differs from other species in the genus by having larger ascomata and setae and wider, asymmetrical ascospores. An amended key to Acanthostigma species is provided along with a discussion of other species previously described from South America. [ABSTRACT FROM AUTHOR]

The phylogeny of Cryptosporella is revised to include recently discovered species. Eight species new to science are described and two new combinations are proposed, raising the total number of species accepted in Cryptosporella to 19. The species delimitation and phylogeny for Cryptosporella are determined based on analyses of DNA sequences from three genes (β-tubulin, ITS and tef1-α), comparative morphology of sexual structures on their host substrate, and host associations. The inferred phylogeny suggests that Cryptosporella has speciated primarily on Betulaceae with 16 species occurring on hosts in that plant family. The host range of most species seems to be narrow with nine species reported from a single host species or subspecies and seven species occurring on plants within a single host genus. A key to species is provided. The known distribution of Cryptosporella is expanded to mountain cloud forests of the provinces of Chiriquí in Panama and Tucumán in Argentina. [ABSTRACT FROM AUTHOR]