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Integrative systematic revision reveals cryptic species in the Calliptamus genus

Chapuis M.P., Benoit L., Foucart A., Dehne Garcia A., Rasplus J.Y., Leménager N., Michel B., Coeur d'Acier A.. 2019. In : 13th International Congress of Orthopterology: Abstract book 2019. Agadir : University Ibn Zohr, p. 120. (Metaleptea). International Congress of Orthopterology. 13, 2019-03-24/2019-03-28, Agadir (Maroc).

The systematics of the genus Calliptamus mainly relies on the shape of the wing and phallic complex, and on color pattern of hind femora of males only. However, geographical variation in these morphological characters hinders species determination. These difficulties may explain why the species delimitation within the genus Calliptamus has been controversial, with numerous confusions, descriptions, synonymies and subspecies. The purpose of this research is to provide a taxonomic review of the genus Calliptamus, based on an integrative approach including morphological, molecular and biological data. Beyond laying the foundations for a revised classification, this project will unravel the historical biogeography of the genus. The Orthoptera Species File currently counts twelve species whose type depositories are known for the Palaearctic genus Calliptamus. We collected with success 9 species, represented by an average of 10 (from 1 to 25) individuals and 6 (from 1 to 17) localities. Since a phylogeny based on a few nuclear genes only may fail to resolve the basal relationships, we used the method of Restrictionsite- associated DNA sequencing (RAD-seq), which showed promises to infer shallow relationships in insects. We showed a success of the method, despite the huge size for the genomes of Calliptamus sp., which we estimated to be ~7.65- 8.39 Gb. We confirmed the two clades defined on the basis of genitalia shape: a Northern group includes species from the cold and wet temperate regions of Eurasia (e.g. C. italicus) and a southern group includes species from the warm and dry mediterranean region (e.g. c. barbarus). we interpreted diversification within these two clades as the result of biogeographic factors, such as isolation in high mountain ranges and islands. We discovered that the species C. barbarus was not monophyletic and we used finer-scale sampling and the COI barcode to understand further its evolutionary history. Morphological analyses of numerous characters, including the hind wing, hind femur, shape of the pronotum and internal and external structures of the male genitalia, are in process to supplement genetic analyses.

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