BIOLOGIA SUBTERRÂNEA
URI permanente para esta coleçãohttps://bdc.icmbio.gov.br/handle/cecav/3
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Item Iron Islands: The importance of iron caves in the eastern Amazon for bat conservation(2024-06-03) Torres, Dayana Ferreira; Bichuette, Maria ElinaThe Carajás region is home to the largest number of iron caves in Brazil, but studies that integrate elements of biological diversity and landscape characteristics are scarce. We present the first study based on the bat cave vulnerability index (BCVI), which uses bats as a key species for prioritizing caves in South America, whose objective was to assess the biotic potential and vulnerability of caves in the Carajás region, determining priority sites and the most effective conservation actions. The study took place from August 2021 to March 2023, where an inventory of the chiropterofauna of 12 caves was carried out. We recorded 16 bat species, two of which are vulnerable to extinction – Furipterus horrens (Cuvier, 1828) and Natalus macrourus (Gervais, 1856) – and two endemics to the Amazon region – Hsunycteris aff. thomasi (Allen, 1904) and Phyllostomus latifolius (Thomas, 1901); as well as one species with insufficient data to delimit its endemicity or threat status (Lonchophyllinae sp.). Mining is the main anthropogenic activity in the region, but tourism is also present and acts as a potential source of disturbance to the caves. The BCVI revealed three high priority caves for conservation and four with medium priority, indicating that these habitats are vulnerable to species loss and population decline due to exposure to anthropogenic activities and habitat destruction, thus requiring more effective conservation strategies. Considering the uniqueness of the subterranean habitats, we recommend re-evaluating the proposals for expanding mining activities, implementing controlled tourist visitation plans and conducting ecological studies and long-term monitoring.Item Coarazuphium auleri sp. n. (Carabidae: Zuphiini), a new troglobitic ground-beetle in Central-Western Brazil(2021-12-12) Pellegrini, Thais Giovannini; Bichuette, Maria Elina; Vieira, LetíciaABSTRACT In this paper, we describe Coarazuphium auleri sp. n. Until now, the species occurred in a single limestone cave, located at Nobres municipality (state of Mato Grosso – Central-Western Brazil). The new species comprises an apterous species from the genus Coarazuphium with the complete absence of hindwings, eyes are composed of very reduced eyes-scars, depigmentation and ommatidia are not evident. We also provide an updated key for species identification of Coarazuphium from the most recently published one. We followed the criteria of IUCN and classified the species as Critically Endangered – CR, IUCN criteria B1ab(iii)+2ab(iii), since the species has a restricted geographical distribution; estimated occurrence length <100 km2; population in few locations and with a continued decline in area, extent, and quality of habitat. According to Brazilian law, the existence of a critically endangered species places the Lagoa Azul cave as one of maximum relevance.Item Under the surface: what we know about the threats to subterranean fishes in Brazil(2021-03) Bichuette, Maria Elina; Eduardo Gallão, JonasThe present work brings information on threats to the subterranean fishes in Brazil. Currently, at least 36 species are known, 22 of which are already formally described. Endemism is the rule for most of them. Regarding their conservation, these fishes are in general considered threatened: and most of the already formally described species are included in national lists of threatened fauna, and only four of them are included in the global list of the IUCN. Regarding habitats, Brazilian subterranean fishes occur in alluvial sediments (part of the hyporheic zone), shallow base-level streams, flooded caves, lakes in the water table, upper vadose tributaries, and epikarst aquifers. We detected 11 main threats, mainly related to agriculture, pasture, and hydroelectric plans, but unmanaged tourism and pollution are also significant threats. Two threats affect a high number of species (physical change of the habitat and food restriction). The river basins with the higher number of identified threats are the upper Tocantins (eight) followed by the upper Paraguaçu (six). Effective proposals to protect this neglected component of the Brazilian biodiversity are still scarce, such as monitoring projects and their function in the subterranean communities, besides education projects aiming to develop public awareness.Item Brasilian troglobitic snails begin to emerge - and are already in danger(2021-03) Cavallari, Daniel Caracanhas ; Cunha, Carlo; Bichuette, Maria Elina; Salvador, Rodrigo Brincalepe ; Santos, Fernanda- New records of the troglobitic Hyalella veredae Cardoso & Bueno, 2014 (Crustacea, Amphipoda, Hyalellidae) from Minas Gerais caves, southeast Brazil, with notes on its natural history(2021-01-18) Zepon, Tamires; Resende, Leonardo; Bueno, Alessandra Angélica de Pádua ; Bichuette, Maria ElinaSince its description, the troglobitic amphipod Hyalella veredae Cardoso & Bueno, 2014 has been recorded only in its type locality, Vereda da Palha cave, in southeastern Brazil. We report this species from three other caves in the region, expanding its distribution by at least 20 km². Inter- and intra-population variability in eye size was observed. Two caves had larger populations, probably due to the presence of biofilm. The species was classified as Critically Endangered due to its restricted area of occurrence, and regional impacts and threats.
Item ECOLOGIA DE PEIXES DE RIACHOS DE CAVERNAS E OUTROS HABITAT SUBTERRÂNEOS(2021) Bichuette, Maria ElinaBrasil desponta como um país rico em cavidades naturais subterrâneas, com mais de 20.000 cavernas cadastradas oficialmente. Além das cavernas, as quais se desenvolvem em diferentes tipos de rocha, há outros habitat subterrâneos (hipógeos) com corpos d’água na forma de drenagens (riachos de nível de base), de afloramentos do freático (zona saturada) em cavernas inundadas ou na forma de poças e lagos dentro de cavidades, além de bolsões de aquíferos superiores formados por água de infiltração na rocha. Em alguns casos, as águas subterrâneas não afloram em cavidades, e sim em aluviões próximos a rios, representando uma zona hiporreica. A ictiofauna subterrânea brasileira é composta por peixes restritos às cavernas e outros habitat subterrâneos (geralmente categorizados como troglóbios/estigóbios) ou por espécies que possuem populações bem estabelecidas nestes habitat, mas que também ocorrem em riachos e corpos d’água da superfície (categorizados como troglófilos). Atualmente há mais de 80 espécies de peixes com populações troglóbias e troglófilas no Brasil. Alguns estudos populacionais para peixes troglóbios/freatóbios apresentam estimativas de tamanhos e densidades populacionais variáveis, geralmente caracterizadas por populações pequenas; uma tendência ao sedentarismo; baixos valores de fator de condição e estratégias de ciclos de vida tendendo ao K dentro do continuum r-K. Estas características são relacionadas às condições abióticas únicas destes habitat, tais como aporte de nutrientes baixo, infrequente e muitas vezes imprevisível, o que pode representar um filtro acentuado. Em relação à conservação, os peixes de riachos de cavernas e de outros habitat subterrâneos encontram-se ameaçados e a maioria das espécies descritas formalmente está inserida em listas de fauna ameaçada no Brasil, apenas quatro espécies foram incluídas e avaliadas globalmente (a piaba Stygichthys typhlops e os bagres Pimelodella kronei, Phreatobius cisternarum e Phreatobius sanguijuela).- Monitoring Brazilian Cavefish: Ecology and Conservation of Four Threatened Catfish of Genus Ituglanis (Siluriformes: Trichomycteridae) from Central Brazil(2021-02-20) Bichuette, Maria Elina; Trajano, EleonoraWe investigated population parameters using the capture-mark-recapture method (Ituglanis passensis and I. bambui) and visual censuses (I. epikasrticus and I. ramiroi). The four species are regionally threatened (Brazilian Red List) and occur in caves of Terra Ronca State Park, São Domingos region, Central Brazil. We conducted seven fieldtrips across three years of dry seasons. For the capture-mark-recapture method, a 400 m long stream inside Passa Três cave, where I. passensis occurs and a 300 m long reach of an upper tributary where I. bambui occurs inside Angélica cave were divided into 20 and 17 study sections, respectively. Catfishes were hand-netted, measured (standard length), weighed, marked by subcutaneous injection of biocompatible pigments, and released. The four species show medium-to-low mean population densities (0.03 ind/m2 0.7 ind/m2). Capture-mark-recapture data pointed to a relatively small population size for I. passensis, restricted to a 1600 m long stream inside Passa Três cave (N = 719) and for I. bambui (N = 246; 300 m of epikarstic drainage). Ituglanis passensis and I. bambui move along relatively small areas with a restricted home range. We observed recruitment patterns and a trend of decrease in condition factor during the dry seasons for I. bambui but not for I. passensis, suggesting that epikarstic waters are probably more limiting concerning food input. Ituglanis passensis and I. bambui showed low growth and consequently high longevity, corroborated by captivity data (20 years). We suggest urgent actions and long-term monitoring projects to effectively protect this unique and endemic ichthyofauna.
Item Spots of high diversity of troglobites in Brazil: the challenge of measuring subterranean diversity(Biodiversity and Conservation, 2016-09) Trajano, Eleonora; Gallão, Jonas Eduardo; Bichuette, Maria ElinaArtigo sobre manchas de alta diversidade de troglobitas no BrasilItem Two new species of freshwater flatworms (Platyhelminthes: Tricladida: Continenticola) from South American caves(Zootaxa, 2016) Souza, Stella; Morais, Ana Laura; Bichuette, Maria Elina; Zanchet, Ana LealItem Geometric morphometrics throws light on evolution of the subterranean catfish Rhamdiopsis krugi (Teleostei: Siluriformes: Heptapteridae) in eastern Brazil(Biological Journal of the Linnean Society, 2014) Bichuette, Maria Elina; Rantin, Bianca; Zaher, Erika Hingst; Trajano, Eleonora