Taxonomy of the rear-edge populations: the case of genus Anterastes (Orthoptera, Tettigoniidae)

• Published in: Organisms diversity & evolution Vol. 23; no. 3; pp. 555 - 575
• Main Authors: Uluar, Onur, Yahyaoğlu, Özgül, Başıbüyük, Hasan Hüseyin, Çıplak, Battal
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.09.2023; Springer Nature B.V
• Subjects: Animal Systematics/Taxonomy/Biogeography; Biodiversity; Biomedical and Life Sciences; Candidate species; Criteria; Developmental Biology; Evolutionary Biology; Genetic analysis; Life Sciences; Morphology; Original Article; Phenotypes; Phylogenetics; Phylogeny; Phylogeography; Plant Systematics/Taxonomy/Biogeography; Pleistocene; Pliocene; Populations; Radiation; Reproductive isolation; Species; Taxonomy; Trailing edges; Tettigoniidae; Glacial relicts; Species delimitation; Rear-edge populations; Taxonomy
• ISSN: 1439-6092; 1618-1077
• DOI: 10.1007/s13127-023-00602-1

The stabilized and the trailing edge glacial relicts are candidate model organisms to be used to link taxonomy to phylogeography. We attempted to establish such a link by considering the taxonomy and phylogeography of the genus Anterastes, consisting of glacial relict taxa/populations. Species delimitation tests indicated 13–22 candidate species in the genus. Analyses suggested inversely related genetic and phenotypic divergence. By integrating these results, we reached the following conclusions. (i) The plausible taxonomical composition is recognizing 16 species in the genus; of these three are new, A. kizkayasiensis sp. n., A. muratdagensis sp. n., and A. boreoanatoliensis sp. n., and the last two are cryptic. (ii) Generic radiation corresponds to three stages as Pliocene, Pleistocene prior to mid-Pleistocene Transition (MPT), and post-MPT. The ultimate ancestor of two species, corresponds to the first and of other 14 to the second and proximate ancestor of all species to the third period. These ages suggest that the pre-MPT ancestors are stabilized edge while those of post-MPT are trailing edge populations. (iii) Since members of the genus demand cold habitats, the isolated relict ancestors on highlands evolved under similar selection pressures, and this led to a conserved phenotype, consequently to cryptic or morphologically poorly diverged species, as genetic data indicate each constitutes a reproductively isolated distinct phylogenetic unit. (iv) Although morphological diagnosability is poor, each species fulfills criteria of several species concepts and can be differentiated by clear allopatric range, providing one of five criteria assumed by Darwin for species delimitation.