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Questions: Leaf traits play an important role in the epiphyll colonization of leaves. Although ferns are common in forest understories, they have been widely ignored as possible host plants. We asked: How does epiphyll colonization (cover, richness, and composition) differ among fern species depending on their leaf longevity and surface wettability? Location: Tropical Biological Station of "Los Tuxtlas", Veracruz (Mexico). Methods: Epiphyll cover was monitored on leaves of six individuals per species after 2, 5, 12, 16.5, and 26 months. Leaf longevity was calculated from leaf turnover rates over 24 months. Leaf wettability was determined through the contact angle technique. Results: All studied fern species had hydrophilic leaf surfaces. Fern species with shorter leaf longevity (14.4–17.8 months) were colonized faster by epiphylls than species with longer leaf life spans (33.9–38.8 months). The area of the oldest leaves was covered to 1.2%–26.1% by foliicolous lichens and to 0.3%–2.2% by green algae. Foliicolous lichens were more species‐rich on Danaea nodosa (27 spp.) than on the other fern species (1–9 lichen spp.). Foliose liverworts thrived on the only riparian fern (3.57%). Only 0.04%–1.1% of the area of plastic substrates was colonized by epiphylls. Conclusions: The hydrophilic leaf surfaces of ferns facilitated the colonization of epiphylls, especially of foliicolous lichens. The speed of epiphyll colonization was faster in ferns with shorter leaf longevity but increased in all species with leaf age. However, the relatively low epiphyll cover on fern leaves and artificial substrates in our study might be related to unfavorable microclimatic parameters. [ABSTRACT FROM AUTHOR]

In the tropics, corticolous lichen richness and cover tend to increase from the trunk base to the top of the crown of trees. In this study we calculated the total beta diversity of the lichen community along a vertical gradient on Quercus laurina in Mexican cloud forest. By comparing the richness and cover of the lichens by zone, we show that foliose and fruticose lichens are a minor component of the total lichen species richness, but have a higher cover than the crustose lichens. Five zones were identified along each phorophyte (n = 15) with a diameter at breast height >40 cm. A total of 92 species were identified. Of these, 38% were found only in a single zone, 51% were shared between the different zones and 11% occurred across all zones. Species richness and cover increased from the lowest to the highest zones of the phorophytes. Dissimilarity in species composition between the zones could be explained by species replacement. An indicator species analysis revealed that only a few species, e.g. Hypotrachyna vexans, H. cf. sublaevigata and Ramalina cf. sinaloensis prefer a particular zone. The results show that the lichen community associated with Quercus laurina phorophytes is highly diverse and suggest that species richness and cover are related to the zone and the various growth forms. [ABSTRACT FROM AUTHOR]

In a continued effort to catalog the numerous phylogenetically detected and predicted species of Cora in the Americas, we focus here on the diversity of the genus in Mexico and the phylogenetic relationships of the taxa present in this area. Based on previous results and new collections, 12 taxa are recognized in Mexico, including eight new species and one new subspecies. The 12 taxa form 11 unrelated lineages within the genus, indicating multiple independent colonization from Central and South America. While the new subspecies is nested within a species known from the northern Andes in South America, the other species are all putative endemics for Mexico, resulting in endemism of 92% at species level and 100% at taxon level. Considering the rather narrow area of origin of the sequenced specimens in southeastern Mexico and the previously documented range of Cora including the northwestern part of the country, plus the underlying topography, we predict that the 12 species and subspecies now known represent only about 20% of the total richness of Cora in the country, and that many more endemic lineages are to be found in the western and northwestern parts (Sierra Madre Occidental). The new taxa from Mexico formally introduced in this study are Cora benitoana sp. nov., with a strongly projecting, cyphelloid hymenophore; C. buapana sp. nov., with elongate, finger-like and partly branched appendages on the lower medullary hyphae; C. dewisanti subsp. mexicana subsp. nov., with a marginally protruding hymenophore; C. guzmaniana sp. nov., with a partly setose lobe surface; C. ixtlanensis sp. nov., a phenotypically cryptic species similar but unrelated to C. terrestris; C. lawreyana sp. nov., with globose hyphal appendages; C. marusae sp. nov., a phenotypically cryptic species similar but unrelated to C. comaltepeca; C. totonacorum sp. nov., a phenotypically cryptic species similar but phylogenetically distant to C. davidia; and C. zapotecorum sp. nov., with a very thinly pilose lobe surface. [ABSTRACT FROM AUTHOR]

An inventory of epiphyte lichens was carried out on 15 phorophytes of Quercus laurina Humb. & Bonpl. located along a mountain ridge in a mountain cloud forest at La Cortadura Ecological Reserve, Coatepec, Veracruz. For each tree the five zones following Johansson's method were distinguished. Ascents were made in selected trees using the single-rope technique, collecting samples along the trunk and some branches of the crown. A total of 126 lichen species were found, belonging to 60 genera, 24 families and 10 orders. The most diverse genus was Graphis (12 species), followed by Parmotrema (9), Hypotrachyna (8), Pertusaria and Usnea (5). Crustose lichens dominated (79%) over foliose (38%) and fruticose (8%) types. Although some species preferred one of the trees while others were common to all (13), no significant differences were observed between phorophytes. The genus Sticta was found in basal and intermediate tree zones; Ramalina and Usnea were recorded in all areas. Twenty-one new records are reported for Mexico, and 21 for the state of Veracruz. [ABSTRACT FROM AUTHOR]