Remarkable micro-endemism and high congeneric richness: eight new cave-restricted species of Pseudochthonius Balzan, 1892 (Pseudoscorpiones, Chthoniidae) from the Brazilian semi-arid

  • Lucas Guimarães Centro de Estudos em Biologia Subterrânea, Departamento de Ecologia e Conservação, Universidade Federal de Lavras, Lavras, MG. CEP 37200-900, Brazil https://orcid.org/0009-0002-7815-3018
  • Rodrigo L. Ferreira Centro de Estudos em Biologia Subterrânea, Departamento de Ecologia e Conservação, Universidade Federal de Lavras, Lavras, MG. CEP 37200-900, Brazil https://orcid.org/0000-0003-3288-4405
Keywords: Cave, conservation, pseudoscorpion, taxonomy, troglomorphism

Abstract

Eight new species of pseudoscorpions belonging to the genus Pseudochthonius Balzan, 1892 are described from the semi-arid region of Brazil. Comprehensive morphological descriptions, diagnostic characters, detailed illustrations, and ecological remarks of the habitats are provided for Pseudochthonius celestialis sp. nov., P. caritas sp. nov., P. patientia sp. nov., P. temperantia sp. nov., P. diligentia sp. nov., P. castitas sp. nov., P. humilitas sp. nov., and P. benignitas sp. nov. In addition, we present a brief discussion of the potential factors underlying the remarkable congeneric species richness observed in this geographically restricted region, as well as the principal threats faced by these species. These findings underscore the importance of conserving caves in order to protect their highly specialized fauna, with particular emphasis on the genus Pseudochthonius, which is increasingly recognized as strongly associated with subterranean environments.

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Published
2026-07-21
How to Cite
Guimarães, L., & Ferreira, R. L. (2026). Remarkable micro-endemism and high congeneric richness: eight new cave-restricted species of Pseudochthonius Balzan, 1892 (Pseudoscorpiones, Chthoniidae) from the Brazilian semi-arid. European Journal of Taxonomy, 1078, 1-43. https://doi.org/10.5852/ejt.2026.1078.3307
Section
Research article