Jonas Eduardo Gallão

Spots of high diversity of troglobites in Brazil: the challenge of measuring subterranean diversity

Subterranean ecosystems are among the most fragile and threatened worldwide. Among organisms living in the subterranean domain, source populations restricted to subterranean habitats are called troglobites, generally distinguished by sets of morphological, physiological, and ecological specializations. The singularities at both systemic (high dark and phylogenetic diversities) and species levels greatly contribute to regional and global biodiversity. However, good descriptive and interpretative knowledge about this diversity, which is important as a basis for effective conservation policies, is lacking especially for tropical areas. We describe and characterize Brazilian karst areas recognized as spots of high diversity of troglobites, highlighting particularly important cave systems. We considered not only taxonomic richness but also indicators of phylogenetic (e.g., presence of relictual taxa) and genetic diversities, the latter based on degree of specialization of individual species, i.e., accumulation of autapomorphies. For this, we used available literature and our own data, both published and unpublished. Only identifications validated by a taxonomist were considered, while all data based on parataxonomy were disregarded. We propose hypotheses based on models of origin of troglobites aiming to explain the differences between karst areas.

Taxonomic distinctness and conservation of a new high biodiversity subterranean area in Brazil

Subterranean environments, even though they do not possess a primary production (photosynthesis), may present high biodiversity, faunistic originality, endemism, phylogenetic isolations and unique ecological and/or evolution events, in addition to rare taxa. Studies investigating the biological diversity in Neotropical caves are relatively rare and recent, and most of them have been conducted in Brazil. We sampled caves from the state of Bahia, northeastern Brazil, and through sampling sufficiency tests and richness estimators, we demonstrate that the normatization for the Brazilian cave laws is not adequate for its conservation and that only α diversity index is not enough to verify faunistic patterns. We suggest that a phylogenetic diversity index be more robust and accurate for conservation purposes, particularly the Taxonomic Distinctness index. Moreover, we propose that the sandstone complex caves from Chapada Diamantina National Park need to be classified as being of high subterranean biodiversity in a global scope.

New records of two endemic troglobitic and threatened arachnids (Amblypygi and Opiliones) from limestone caves of Minas Gerais state, southeast Brazil.

Abstract Background The endemic and threatened troglobites (organisms restricted to caves) Charinus eleonorae (Amblypygi) and Iandumoema uai (Opiliones), both from Olhos d’Água cave, located at Peruaçu Caves National Park (southeast Brazil), have their distribution expanded for a new locality inside of the National Park (Lapa do Cipó cave), extending their distribution at least in 9.5km2. New information This new data suggest that these arachnids can be in a differentiation process and/or there are several possibilities of dispersion in the karst of Peruaçu. Indeed, a revision of their categorical status at IUCN Red List is necessary. We herein report a new distribution range (Lapa do Cipó cave) of the troglobitic species I. uai and C. eleonorae, which are, to date, known to occur in the Olhos d’Água cave, located at the Peruaçu Caves National Park (PCNP).

Brazilian obligatory subterranean fauna and threats to the hypogean environment

Abstract The subterranean environment harbors species that are not capable of establishing populations in the epigean environment, i.e., the obligatory subterranean species. These organisms live in a unique selective regime in permanent darkness and usually low food availability, high air humidity in terrestrial habitats, and low temperature range allied to other unique conditions related to lithologies and past climatic influences. The pressure to increase Brazil’s economic growth relies on agricultural/pastoral industries and exporting of raw materials such as iron, limestone, ethanol, soybean, cotton, and meat, as well as huge reservoir constructions to generate electricity. Mining (even on a small scale), agricultural expansion, and hydroelectric projects are extremely harmful to subterranean biodiversity, via the modification and even destruction of hypogean habitats. The Brazilian subterranean species were analyzed with respect to their distributions, presence on the IUCN Red List, and current and potential threats to hypogean habitats. A map and three lists are presented, one with the described obligatory subterranean species, one with undescribed taxa, and one with the current and potential threats to the hypogean environment. To date, 150 obligatory subterranean species have been recorded in Brazil, plus at least 156 undescribed troglomorphic taxa, totaling 306 Brazilian troglobites/obligatory cave fauna. We also analyzed the current and potential cave threats and the conservation actions that are underway to attempt to compensate for loss of these habitats. In according to the Brazilian legislation (Decree 6640) only caves of maximum relevance are fully protected. One strategy to protect the subterranean fauna of Brazil is the inclusion of these species in the IUCN Red List (one of attributes that determines maximum relevance for caves); however, one of the IUCN assumptions is that the taxa must be formally described. It is clear that the description and proposed protection of Brazilian subterranean biodiversity depends on more systematics studies.