New species of Trechus Clairville, 1806 of the clade of T. saxicola from the cantabrian chain, Asturias, Spain - biogeography and speciation (Coleoptera: Carabidae: Trechinae).

New species of Trechus Clairville, 1806 of the clade of T. saxicola from the cantabrian chain, Asturias, Spain - biogeography and speciation (Coleoptera: Carabidae: Trechinae).Trechus odontopeosn. sp., T. croceusn. sp., T. hyperythrosn. sp., T. enedaphosn. sp., T. pongensisn. sp. and T. riberain. sp. are described from Asturias, Cantabrian area in Spain. The species were collected in deep subterranean and edaphic environment. Morphological evidences demonstrate that the new species are related to Trechus saxicola Putzeys, 1870. The molecular study shows that, in addition to the species described, the clade of Trechus saxicola is composed of T. apoduvalipenis Salgado & Ortuno, 1998, T. bourdeaui Fresneda, Valenzuela & Faille, 2015, T. marcilhaci Pham, 1987, and T. saxicola. The taxonomy of the group is discussed and illustrations of structures showing the differences between these species are provided, along with distribution data and biogeographical comments. The current distribution of the group seems to result from multiple phenomena of vicariance. The origin of the diversification of this clade seems related to the climate changes that occurred during the beginning of the Pleistocene, which led to the fragmentation of the area of original distribution in several isolates confined in distinct karstic refugia. Possibilities of colonization by passive transport (rivers Navia and Sella) as well as likely case of hybridization are suggested in the clade.urn:lsid:zoobank.org:pub:809C5C4C-D0EB-4690-BDCD-D96363A0F8B