Navegando por Assunto "Amphibians"

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Artigo
First molecular evidence of frogs as a food source for sand flies (Diptera: Phlebotominae) in Brazilian caves
(2021-04-14) Costa, J.C.R.; Santos, C.S.
Genus and species of phlebotomine sand flies have been recorded and described in caves in Brazil, but no study has provided the food source used by sand flies in these environments. Herein, we identified the blood source used by sand fly species in caves located at “Quadrilátero Ferrífero” (QF), Minas Gerais state. Specimens were manually collected near or on anurans inside ferruginous caves in Serra do Gandarela National Park and Serra do Rola Moça State Park. Males and females were placed in vials with 70% alcohol and stored at −10°C. Females engorged, after specific identification, had DNA extracted and followed for PCR amplification using specific primers. Sequencing was analyzed in the GenBank and Barcode of Life. A total of 198 specimens were collected (107 females and 91 males), all of them belonging to species Sciopemyia aff. microps (88.89%), Sciopemyia sordellii (10.61%), or Martinsmyia oliveirai (0.50%). When it comes to the females, 89 were S. aff. microps and 18 S. sordellii. Nineteen engorged females of S. aff. microps were analyzed and most of them (n=18) presented blood from Bokermannohyla martinsi and one contained blood from Scinax fuscovarius. The blood present in engorged females of S. sordellii (n=4) was from B. martinsi. Sciopemyia genus specimens are commonly found in collections carried out inside natural caves, but this was the first study to prove that females of this genus feed on cold-blooded animals in nature.
Artigo
The agricultural transformation of Brazil’s Cerrado is influencing the diversity and distribution of tadpoles via lentification
(Biodiversity and Conservation, 2024) With, Kimberly A.; Ramalho, Werther P.; McIntosh, Tanner.; Signorelli, Luciana
More than half of Brazil’s Cerrado has been converted to agricultural land use, threatening its rich biodiversity that includes > 200 anuran species, most of which have aquatic larvae and are thus doubly susceptible to the environmental impacts of agriculture. Past research has largely focused on how land-use change affects adult anurans, which ignores potential impacts on the critical larval stage. We therefore investigated how agricultural land use (250–1000 m scale) and the local pond environment affect the diversity and distribution of tadpole assemblages across the central Cerrado. Tadpole richness declined significantly with increasing cropland within 250 m of ponds and with increasing water pH in permanent ponds. Permanent ponds are more prevalent in agricultural areas where streams are impounded to provide water for irrigation and livestock, and water pH increases with increasing agriculture, likely due to the widespread use of agricultural lime in the Cerrado. Tadpole communities exhibited high beta diversity (81–86% dissimilarity), with species replacement rather than nestedness accounting for 90–97% of species differences between ponds, which was largely driven by hydroperiod. Six species accounted for 70% of the dissimilarity, with most species either more abundant or found only in temporary ponds. Increased lentification, a corollary of agricultural land use, is profoundly altering tadpole assemblages, which has consequences for overall anuran diversity in the Cerrado given that permanent ponds support a different and less-diverse larval assemblage than ephemeral wetlands. Anuran conservation in the Cerrado should therefore additionally consider maintaining or restoring wetland hydrology and native-vegetation buffers around wetlands.