Una nueva especie troglobiomorfa de Trechus Clairville, 1806 y evidencias de colonizaciones múltiples del medio subterráneo de los montes cantábricos (Coleoptera, Carabidae, Trechinae)

Abstract

We describe Trechus (Trechus) valenzuelai n. sp. from the Cantabrian area of Spain: Sierra de Cuera, Asturias. The species was collected in the subterranean environment, in caves and dolines. Morphological examination revealed that the new species is sister to Trechus escalerae Abeille de Perrin, 1903 within the T. saxicola clade. A synapomorphy of the male genitalia, shared by T. valenzuelai n. sp. and T. escalerae, is described and illustrated: the endophallus has a sclerotised piece shaped like a club, elongated, robust, strongly sclerotised and with a membranous sac covered with small spicules at the base. We discuss the taxonomy of the new species and provide illustrations of structures showing the differences between T. escalerae and T. valenzuelai n. sp., along with biogeographical and distributional data and hypotheses regarding the speciation events based on previously pubished molecular data, and the geological structure and the palaeoclimatology of their geographical area. We hypothesize that in this clade, the colonization of the subterranean environment was the result of multiple, independent and simultaneous colonization processes. A lectotype is designated for T. escalerae.