Description and ecology of a new species of the cricket genus Endecous (Orthoptera: Grylloidea: Phalangopsidae) in the speleological province of Arcos-Pains-Doresópolis, Southeastern Brazil

Abstract

A new cricket species of the genus Endecous Saussure, 1878 is described in the present work found in the speleological province of Arcos-Pains-Doresópolis, which belongs to the limestone group Bambuí, Brazil. Moreover, the spatial distribution of the new species was related to the species Eidmanacris sp., which co-occurs with the former in several caves. Relationships between species abundance and horizontal projection, number of entrances and environmental stability of the caves where these species coexist were evaluated. The presence of bilateral symmetry in individuals of Endecous painensis n. sp. perhaps due to environmental stress caused by mining activities surrounding the cave was also tested. Endecous crickets are commonly observed in the caves, for which the preference by distinct microhabitats and generalist strategies may be key factors explaining colonization and segregation in relation to other cricket species in subterranean habitats. The generalist lifestyle of the here described species may attenuate the effects environmental stresses over development.

Persisting while changing over time: modelling the historical biogeographic of cave crickets (Orthoptera, Grylloidea) in Neotropics

“…Analysis in different temporal scenarios (21 ka, 6 ka, 0 ka and RCP8.5) based on the current Endecous distribution showed that these crickets almost did not reach the north of the Amazon biome. The same pattern was observed for the sympatric genus Eidmanacris Chopard, 1956(Castro-Souza et al 2020b, a group that is also dependent on remnants of humid forests and cave habitats (De Campos et al 2021). Although these two genera can co-occur inside caves, there is spatial segregation between their populations, with Endecous inhabiting deeper regions and Eidmanacris occurring near cave entrances, which would avoid competitive exclusion (Castro-Souza et al 2020b, Paixão et al 2017.…”

“…In particular, many South American cave phalangopsidae (e.g. Adelosgryllus, Endecous, Phalangopsis and Strinatia) (Campos et al 2017, Castro-Souza et al 2020b, Cigliano et al 2022, Junta et al 2020, Merlo et al 2022, Mesa et al 1999) reveal pre-adaptations reported for other cave crickets (Desutter-Grandcolas 1993;Desutter-Grandcolas 1997;Heads 2010), such as eye size reduced, loss of ocelli, absence of auditory tympana and body discoloration. However, to confirm that the traits are pre-adaptations, it is necessary to evaluate them together with the habitat from a phylogenetic perspective (Desutter-Grandcolas 1997).…”

“…In particular, the genus Endecous (Orthoptera: Grylloidea: Phalangopsidae) could be a good model group for large-scale studies as they present species occurring in both epigean and hypogean environments (Bolfarini & Bichuette 2015, Castro-Souza et al 2020a, 2020b, Souza-Dias et al 2014. In addition, resources derived from cave crickets, such as dung, bodies, carcases and eggs, can directly be consumed by several other cave invertebrate species, thus contributing to the structuring of subterranean communities (Lavoie et al 2007, Mammola et al 2019a, Taylor 2003, Taylor et al 2005.…”