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

Maria Elina Bichuette,Tamires Zepon,Diego Monteiro Von Schimonsky,Jonas Eduardo Gallão,Luiza Bertelli Simões

doi:10.3897/subtbiol.29.30418

Abstract

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.

Highlights

The subterranean fauna consists of organisms able to survive in peculiar conditions of the environment, as the permanent darkness, the high relative humidity of the air and stable temperatures at the deepest zones (Barr 1968)
We collected a total of 1,941 individuals of 344 morphospecies belonging to 128 families, 37 orders and ten classes (Appendix 1) in both regions: 287 morphospecies and 1,554 individuals were from São Domingos and 122 morphospecies and 387 individuals were from Posse
In São Domingos, Lapa Angélica was the richest and most abundant cave, with 203 morphospecies and 865 individuals, followed by Terra Ronca II cave with 88 morphospecies and 274 individuals

Summary

Introduction

The subterranean fauna consists of organisms able to survive in peculiar conditions of the environment, as the permanent darkness, the high relative humidity of the air and stable temperatures at the deepest zones (Barr 1968). These inherent features may act as an environmental filter (see Fernandes et al 2016 to opposite view) in such a way that only part of the epigean taxa is capable to colonize and establish hypogean populations. Because of its unique conditions and the high degree of endemism, subterranean environments are fragile and sensitive to environmental changes, especially those regarding anthropic activities (Culver 1986, Gibert and Deharveng 2002, Trajano and Bichuette 2006). Most often in tropical caves, the seasonal oscillation is of great importance in the dynamics of the subterranean environments (Trajano 2000)

Methods

Results

Conclusion