Distribuição multitemporal do gênero Endecous Saussure, 1878 (Orthoptera: Grylloidea: Phalangopsidae) na América do Sul e descrição de uma nova espécie para o Brasil

Abstract

The present dissertation is developed mainly within the field of knowledge of Bioespeleology, using a group of crickets (Endecous Saussure, 1878) that is distributed widely through neotropical caves. This study is divided into two chapters written according to the publishing guidelines of two scientific journals. In chapter 1, we worked on a local scale, with the main objective of describing a new species of cricket of the genus Endecous, present in the speleological province of Arcos-Pains-Doresópolis, Minas Gerais, Brazil. In addition, it was discussed how the abundance of the new species, Endecous "painensis" sp. n. is related to the abundance of the sympatric species Eidmanacris sp. and also if abundances of these crickets are related to the horizontal projection, the number of entrances and the environmental stability of the caves where such species co-exist. Finally, it was tested whether a cave population of Endecous "painensis" sp. n. under environmental stress (presence of a mining in the surroundings of the cave) showed bilateral symmetry deviations when compared to two populations far from mining areas. In this chapter the great capacity of cave colonization by the genus Endecous was reinforced, and it is noteworthy that the preference for distinct microhabitats and generalist strategies of these crickets may be the key to explain colonization and segregation with other cricket species in caves. In addition, it is concluded that the generalist way of life of this new species may possibly mitigate the effects on development in a stressful environment. For Chapter 2, we worked on a macroecological scale, using ecological niche modeling techniques (ENMs) to predict the potential distribution of occurrence in the present, past (mid - Holocene - 6,000 years - and Last Glacial Maximum - LGM, 21,000 years), and future (year 2100 - RCP8.5) for the genus Endecous. Therefore, we used abiotic predictors of the external environment in order to predict the potential distribution of the genus in the different scenarios, since, although abundant, crickets of this genus are not restricted to the cave environment. It was observed that the ancestors of these crickets have possibly colonized the caves in the past, since distinct rearrangements occurred for the different temporal scenarios predicted for the past and present. Furthermore, in the face of a global warming scenario, the potential distribution of these organisms may undergo severe changes. It is plausible to assume that the displacement of the potential distribution of these crickets in the future scenario may represent strong impacts on the structure of most of the underground populations of the genus, with potential consequences for terrestrial subterranean communities, due to the diverse interactions and high abundance of this group in Brazilian caves. Finally, we emphasize the importance of ENMs studies to predict and preserve organisms in caves, and the role of climatic oscillations in the rearrangement of the distribution of Endecous species is evident. In addition, we highlight the importance of caves as possible refuges for the maintenance of the species of this genus, in the face of a global warming scenario and the loss of favorable surface habitats.