Associações entre heterópteros Emesinae e aranhas em cavernas calcárias de Minas Gerais, sudeste do Brasil

Emesine bugs, within several genera, are recorded from caves around the world, but have been regarded as uncommon in these habitats. Many emesines have ecological relationships with spiders, as kleptoparasites, predators, or both. However, cave emesines are apparently rarely involved in these arachnophilous relationships, and only two examples have been previously documented. Recent studies in limestone caves at Presidente Olegário in northwestern Minas Gerais, Southeastern Brazil revealed the presence of four emesine species, two of which (Emesa mourei Wygodzinsky, 1946 and Phasmatocoris sp.) were associated with spiders, probably as kleptoparasites. The spiders recorded in these associations were Mesabolivar aff. tandilicus (Mello-Leitão, 1940) (Pholcidae) and Loxosceles similis Moenkhaus, 1898 (Sicariidae). The only non-emesine reduviid recorded in Presidente Olegário caves was Zelurus zikani (Costa Lima, 1940). We discuss these rarely recorded associations between cave emesines and spiders and the importance of protecting Presidente Olegário caves.Keywords: Arachnophily, Reduviidae, Pholcidae, Sicariidae, subterranean environment.Emesíneos cavernícolas, pertencentes a vários gêneros, são registrados em cavernas ao redor do mundo, porém são considerados menos abundantes nesse habitat. Muitas espécies possuem relações ecológicas com aranhas, como cleptoparasitas, predadores ou ambos. Entretanto, é aparentemente raro esse tipo de associação com aranhas em cavernas e apenas dois exemplos foram documentados anteriormente. Estudos recentes em cavernas calcárias de Presidente Olegário, no noroeste de Minas Gerais, sudeste do Brasil, revelaram a presença de quatro espécies de Emesinae, sendo que duas delas (Emesa mourei Wygodzinsky, 1946 e Phasmatocoris sp.) estavam associadas com aranhas, provavelmente como cleptoparasitas. As aranhas registradas nessas associações foram Mesabolivar aff. tandilicus (Mello-Leitão, 1940) (Pholcidae) e Loxosceles similis Moenkhaus, 1898 (Sicariidae). O único reduvídeo não Emesinae registrado nas cavernas de Presidente Olegário foi Zelurus zikani (Costa Lima, 1940). Discutem-se brevemente essas raras associações entre emesíneos cavernícolas e aranhas e a importância de se proteger as cavernas de Presidente Olegário.Palavras-chave: Aracnofilia, Reduviidae, Pholcidae, Sicariidae, ambiente subterrâneo

Richness and taxonomic distinctness of cave invertebrates from the northeastern state of Goiás, central Brazil: a vulnerable and singular area

The karst area of the northeastern state of Goiás comprises two main municipalities: São Domingos and Posse. São Domingos is inside the limits of a Full Protection Conservation Unit known as Parque Estadual de Terra Ronca (PETeR), where a high number of caves occurs, some of them surpassing 10 km in length. Despite their protection by law, uncontrolled tourism has been threatening the integrity of the unique and fragile cave systems of São Domingos. On the other hand, the caves of Posse are much less visited, with its subterranean fauna poorly unknown and are strongly threatened by the urban areas and mining activities in the vicinity. We conducted six systematic surveys of invertebrates in 12 caves, seven of which are located in São Domingos and five in Posse, between 2010 and 2012. Immediately outside the caves, we sampled several microhabitats for comparison. We estimated richness, abundance, and taxonomic distinctness of the communities. We recorded 1,941 individuals of 344 morphospecies. Caves from São Domingos showed a higher species richness and were more taxonomic distinct than caves from Posse. Most morphospecies were considered troglophiles (188). We also found one trogloxene and one troglobite, as well as nine troglomorphic taxa that possibly are troglobitic as well. Both regions have markedly singular caves regarding its subterranean fauna, with high values of taxonomic distinctness. However, the richer caves were not necessarily the most taxonomic distinct. Conservation measures are especially necessary in the region of Posse, where caves are not legally protected and are within an area of significant urbanization. Cave entrances of Posse are near deforested vicinities, in some cases with domestic wastes and cement plants nearby

Fauna terrestre da maior cavidade em granito do Hemisfério Sul, sudeste do Brasil: um habitat negligenciado

Studies focusing cave fauna on granitic caves are relatively rare when compared to carbonatic ones and no one considered replicas in the sampling to test fauna distribution patterns. We describe the terrestrial fauna of Riacho Subterrâneo cave through four sampling occasions (replicas) in different seasons. We analyzed seasonality and substrate preference of terrestrial invertebrates and discussed the importance of this neglected habitat as a refuge for fauna. Furthermore, we stressed the importance of the replicas in order to detect subterranean biodiversity patterns. The cave represents the greatest richness considering igneous rocks in Brazil (199 taxa) and has an important role as refuge for epigean fauna, besides the maintenance of troglophilic and trogloxene populations.Keywords: subterranean microhabitats, igneous rock, Neotropical Region, seasonality, refuge.Estudos com foco em fauna de cavidades graníticas são relativamente raros comparados àqueles em rochas carbonáticas, e nenhum deles considerou a realização de réplicas para teste de padrões de distribuição da fauna. Descrevemos a fauna terrestre da Gruta do Riacho Subterrâneo por meio de quatro ocasiões de amostragem (réplicas) em diferentes estações do ano. Analisamos a influência da sazonalidade e a preferência por substratos da comunidade de invertebrados terrestres e discutimos a importância deste habitat negligenciado como refúgio para a fauna. Ainda, discutimos a importância da realização de réplicas para detectar padrões de biodiversidade subterrânea. A cavidade apresenta a maior riqueza biológica dentre as cavidades em rochas ígneas no Brasil (199 táxons) e desempenha um papel importante como refúgio para fauna epígea, além de manutenção de populações troglófilas e trogloxenas.Palavras-chave: micro-habitats subterrâneos, rocha ígnea, Região Neotropical, sazonalidade, refúgio

Zonação e estratificação da fauna subterrânea de Presidente Olegário, noroeste de Minas Gerais

There are several factors that may influence the richness and distribution in the subterranean fauna, just as resource avaiability and distribution, the local climate characteristics, the quality of the habitat and the vegetation surrounding it. Hypogean systems present high degree of endemism and their populations present as intrinsic characteristics a reduced number of individuals and are usually dependent on nutrients imported from the surface. These factors, among other results in an extremely fragile hypogean environment. This study aimed to verify the taxonomics groups that occur in Presidente Olegário caves, located at northwestern of Minas Gerais, Brazil. Along with that it aimed to verify through statistical tests as the biotics and abiotics variables influence the distribution and composition of subterranean fauna of this region. For these purposes, collections using combinated sampling methods occured in five different visiting occasions, contemplating both dry and rainy periods. The Presidente Olegário karst area presented high richness (386 species in seven caves sampled). Four new species and three new records besides four troglomorphic morphotypes were registrated. It was also verified how essential the execution of replics are, since the detection of rare species increases with the number of samplings. The caves presented high taxonomic distinctness and therefore, presented high faunistic singularity. The species distribution is positively associated to abiotics variables (temperature, relative humidity and precipitation), which can promote niche diversification when changed and consequently increase the local diversity. Therefore faunistic patterns can be changed for sazonality influence in the subterranean environment. High values of richness and abundance were registered at the entrance and twilight zones, where higher amounts of organic matter were found. The fauna stratification occurred with some taxa occurring preferentially in certain substrates types, which is probably related to food resources availability. Therefore, the terrestrials communities studied seem to be strutured based on energy resources and thus, a food web was built for these caves. Several impacts are present in Presidente Olegário, such as pasture, agriculture and future projects of gas extration and hidreletrics. Thus, this region with high richness and faunistic singularity and its area of influence should be considered as priority for conservation.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Há diversos fatores que influenciam a riqueza e a distribuição da fauna no ambiente subterrâneo, como a disponibilidade e distribuição dos recursos, as características climáticas locais, a qualidade do habitat e a cobertura vegetal do entorno. Sistemas hipógeos apresentam elevado grau de endemismo, e suas populações apresentam como características intrínsecas um número reduzido de indivíduos e, geralmente, são dependentes de nutrientes importados da superfície. Estes fatores, dentre outros, tornam o meio hipógeo extremamente frágil. Este estudo teve como objetivos verificar quais grupos taxonômicos ocorrem em cavernas de Presidente Olegário, noroeste de Minas Gerais, Brasil, além de verificar, por meio de testes estatísticos, como as variáveis bióticas e abióticas influenciam na distribuição e composição da fauna subterrânea dessa região. Para isso, foram realizadas coletas utilizando métodos combinados de amostragem ao longo de cinco ocasiões de visita, contemplando períodos secos e chuvosos. A área cárstica de Presidente Olegário apresentou elevada riqueza (386 espécies em sete cavernas amostradas). Foi registrada a ocorrência de quatro espécies novas, três registros novos, além de quatro morfotipos troglomórficos. Também se verificou a necessidade e importância da realização de réplicas, uma vez que a detecção de espécies raras aumenta com o número de amostragens. As cavernas apresentaram elevada distinção taxonômica e, portanto, possuem elevada singularidade faunística. A distribuição das espécies está associada de forma positiva às variáveis abióticas (temperatura, umidade relativa e precipitação), as quais podem promover a diversificação de nichos quando alteradas e, consequentemente, aumentar a diversidade local. Ainda, padrões faunísticos podem ser alterados por influência da sazonalidade no ambiente subterrâneo. Maiores valores de riqueza e abundância foram registrados nas zonas de entrada e penumbra, onde havia maior quantidade de matéria orgânica. Foi observada a estratificação da fauna subterrânea, com alguns táxons ocorrendo preferencialmente em determinados tipos de substratos, o que provavelmente está relacionado à disponibilidade de recursos alimentares. Portanto, as comunidades terrestres das cavernas estudadas parecem ser estruturadas com base em recursos energéticos e, assim, foi proposta uma teia alimentar para essas cavernas. Diversos impactos e ameaças estão presentes em Presidente Olegário, como atividades agropecuárias, projetos futuros de extração de gás e construção de pequenas centrais hidrelétricas. Assim, essa região com elevada riqueza e singularidade faunística e toda sua área de influência deve ser considerada como prioritária para conservação

The role of turnover in structuring subterranean aquatic communities in Southeastern Brazil

Abstract Similarly to other animal communities, the diversity of subterranean aquatic fauna is influenced by several factors and processes, such as habitat fragmentation, dispersion, environmental heterogeneity, and physical and chemical water characteristics. Here, we studied cave aquatic communities of the Alto Ribeira hydrographic basin, regarding troglobitic and non-troglobitic species, located in a single karst area to evaluate the influence of sub-basins in fauna differentiation. We investigated how abiotic variables (flow, electrical conductivity, temperature, pH, and substrate) influence the fauna composition and the contribution of beta diversity components (nestedness and turnover) in explaining communities’ dissimilarities. Fauna composition differed between sub-basins, as most species did not co-occur in different caves. Caves with higher flow and substrate diversity were the richest. In addition, each cave community was influenced by a unique set of abiotic variables. Dissimilarity among caves was mainly explained by turnover, and our findings suggest the restricted species distribution could be due to ecological (e.g., limited dispersion capacity, tolerance to abiotic variables), hydrogeological (e.g., dispersion barriers, isolation of sub-basins), and historical (e.g., colonization, paleoclimatic events) factors and processes. Therefore, different elements are responsible for determining the composition of cave aquatic communities in different sub-basins, reflecting the variability within a single karst area

Characterization and perspectives on studies of subterranean invertebrate communities in Latin America

Studies about subterranean fauna in Latin America were intensified in the last decades. Many research are species description, but other knowledge areas have been studied, such as subterranean invertebrates communities. This study aims to characterize studies about these communities in Latin America countries. We made a bibliographic survey of published papers in scientific journals and bulletins of speleology groups, and different aspects were verified, like localities (country), publish date, number of sampled caves, use of tests and statistical analyzes and sample effort. Of the 20 Latin America countries, we not found those studies for ten (10) of them (Bolivia, Costa Rica, El Salvador, Haiti, Honduras, Nicaragua, Panama, Paraguay, Dominican Republic, and Uruguay). We accessed a total of 164 published studies, of which the most was conducted in Brazil (69), followed by Mexico (52), Venezuela (17) and Cuba (11). In Brazil, most of studies was published in the last two decades (2000-2017), in Mexico in the 70’s, in Venezuela between 80’s and 2009 and in Cuba in 70’s and 90’s. Except for Brazil, where the most of studies explored the influence of biotic and abiotic factors in the communities, all countries published mainly faunistic inventories about only an unique cave or region. Thus, they do not present tests and statistical analysis and, sometimes, neither ecological discussion. Moreover, many publications do not have information about number of sample occasions and most of Brazilian studies did only one sample occasion. That makes it harder both the ecological approach that permits the verification of patterns that acts in the communities structuring and the comparison of data from different regions. Therefore, although the knowledge of subterranean invertebrates communities has increased, the Latin American has a huge potential to be explored in relation to areas with few or no studies, and to more consistent ecological studies

How much we know about Brazilian subterranean aquatic fauna

The first study concerning Brazilian subterranean fauna was the description of the phreatobitic fish Phreatobius cistenarum Goeldi, 1905, followed by the stygobitic fish Pimelodella kronei (Miranda Ribeiro, 1907). After that, biospeleological studies mainly focused on terrestrial taxa description, and in 1972 the first stygobitic invertebrate, Aegla cavernicola Türkay, 1972 (Decapoda, Aeglidae), was described. Here, we provided an overview of the Brazilian subterranean aquatic fauna knowledge. To date, ca. 270 troglobitic species are described, of which 64 are aquatic (22 fishes; 42 invertebrates) and 13 have amphibian habits (all isopods). Considering aquatic species, 15 species were described between 1905 and 1999, 13 in the 2000s, 27 in the 2010s, and 9 in the 2020s. Furthermore, new stygobitic species were confirmed by experts but not published due to the deficit of trained specialists. Brazil has the second higher world diversity in stygobitic fishes, and data about habitat, biology, and ecology are available. Most of them are generalist carnivorous occurring in alluvial sediments, shallow base-level streams, flooded caves, lakes in the water table, upper vadose tributaries, or epikarst aquifers. Usually, they have small populations, but some species have large population sizes for the subterranean patterns. Some species have regression of the agonistic, cryptobiotic, and photophobic behaviors and regression of the circadian rhythms compared to their epigean relatives. Moreover, some species have morphological and behavioral intraspecific differences. Around 50 fish species have stygophilic populations, and some studies compared biological and morphological aspects of epigean and hypogean populations. There are available data about the habitat and natural history of the described stygobitic invertebrates, of which most are amphipods and planarians. Few phylogenetic relicts and epikarstic species were described. Usually, stygobites have restricted distribution in a micro-basin or are endemic within a unique cave and have small populations. Morphological and populational studies are available for few taxa (e.g., decapods and gastropods), as well as behavior studies. Community studies discuss species richness and distribution related to abiotic variables, lithology, and responses to disturbances; only a study is about epikarstic communities. For stygophilic species, there are mainly studies on distribution patterns and new records. Concerning amphibian species, five species were described in the 2010s and eight in the 2020s, with notes on their natural history and habitat. The main threats to the subterranean aquatic fauna are pollution by pesticides, decreasing aquifer levels due to deforestation and water exploitation for irrigation, headwaters of rivers outside protected areas, suppression of habitats by mining and hydroelectrical activities, allied to the current dismantling and attacks to the Brazilian environmental policies. To date, 46 stygobites (16 fishes and 30 invertebrates) and five troglobitic amphibians are on the Brazilian Red List

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

Since 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