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The study of the environmental features affecting amphibian communities is a priority task for addressing effective conservation initiatives. In the southern edge of the Apennines (Sila Massif, Calabria Region, Italy), we surveyed the distribution of amphibians in lotic freshwater habitats (eight rivers, 17 sampling stations, 87 transects) and recorded nine environmental variables, including the occurrence of potential predators (fish and Eurasian otter Lutra lutra), potentially affecting the distribution and breeding success of amphibian species. A total of seven amphibian species was recorded (75.9% of transects). Fish occurred in all rivers while the otter was found in four rivers (Amato, Lese, Neto, and Savuto). Illuminance and bank heterogeneity were the main factors affecting amphibian reproduction, while neither otter nor fish presence showed significant effects on the amphibian community. Overall, habitat complexity and coevolution history seemed to shape the distribution of amphibians and their breeding sites, while the ongoing recolonization of the study area by the otter is expected to have a negligible impact on the richness of the amphibian community. [ABSTRACT FROM AUTHOR]

The aim of the present paper was to check for the presence of cerebrovascular dystroglycan in vertebrates, because dystroglycan, which is localized in the vascular astroglial end‐feet, has a pivotal function in glio‐vascular connections. In mammalian brains, the immunoreactivity of β‐dystroglycan subunit delineates the vessels. The results of the present study demonstrate similar patterns in other vertebrates, except for anurans and the teleost groups Ostariophysi and Euteleostei. In this study, we investigated 1 or 2 representative species of the main groups of Chondrichthyes, teleost and non‐teleost ray‐finned fishes, urodeles, anurans, and reptiles. We also investigated 5 mammalian and 3 bird species. Animals were obtained from breeders or fishermen. The presence of β‐dystroglycan was investigated immunohistochemically in free‐floating sections. Pre‐embedding electron microscopical immunohistochemistry on Heterodontus japonicus shark brains demonstrated that in Elasmobranchii, β‐dystroglycan is also localized in the perivascular glial end‐feet despite the different construction of their blood–brain barrier. The results indicated that the cerebrovascular β‐dystroglycan immunoreactivity disappeared separately in anurans, and in teleosts, in the latter group before its division to Ostariophysi and Euteleostei. Immunohistochemistry in muscles and western blots from brain homogenates, however, detected the presence of β‐dystroglycan, even in anurans and all teleosts. A possible explanation is that in the glial end‐feet, β‐dystroglycan is masked in these animals, or disappeared during adaptation to the freshwater habitat. [ABSTRACT FROM AUTHOR]