Diversification of subgenus Calathus (Coleoptera: Carabidae) in the Mediterranean region – glacial refugia and taxon pulses

Abstract

Aim To investigate the effects of Pleistocene climatic variations on the diversification rate of the subgenus Calathus (Coleoptera: Carabidae), and to estimate the role of vicariance and dispersal for explaining current distributional patterns. Location Western Palaearctic Region, particularly the Mediterranean Basin. Methods Fragments of the mitochondrial cox1–cox2 and the nuclear 28S and EF1α genes were analysed by Bayesian inference. Lineage divergence times were estimated using a Bayesian relaxed molecular clock. Three diversification rate analyses were conducted, namely gamma (γ)‐statistic, birth–death likelihood (BDL) test and survival analyses, in order to test departures from a constant rate model of diversification. A Bayesian approach to dispersal–vicariance analysis was developed to reconstruct the most probable ancestral area of subgenus Calathus and subsequent events of dispersal and colonization. Results A constant rate of speciation events from the late Miocene onwards was found for the subgenus Calathus, whereas recent Pleistocene climatic oscillations played an important role only in shaping intraspecific diversity. Overall diversification patterns for the subgenus are best explained by at least four westward dispersal events from the eastern Mediterranean Basin. Three distinct phylogroups were found for the widely distributed Calathus fuscipes. Incongruence between mitochondrial and nuclear loci was found for a number of species. Main conclusions Diversification analyses suggest either a constant rate of diversification (BDL analysis) or a decrease in diversification rates for the subgenus (survival or γ‐statistics analyses), but not an increase related to the effects of glaciation cycles. Diversification patterns in the subgenus Calathus agree with predictions of the taxon pulse model. From the middle Miocene onwards the Anatolian Peninsula was possibly the main centre of diversification, with successive dispersal events towards the western Mediterranean Basin. Range expansion and secondary contact zones are postulated between members of different phylogroups in C. fuscipes.

Diversification patterns and processes of wingless endemic insects in the Mediterranean Basin: historical biogeography of the genus Blaps (Coleoptera: Tenebrionidae)

“…Contrary to some studies where non‐significant change in diversification rates were found (Trizzino et al ., ), our results are broadly in agreement with results dealing with the diversification of other wingless Mediterranean‐wide taxa, such as cave crickets (Allegrucci et al ., ) and Calathus carabid beetles (Ruiz et al ., ). These groups show an east‐to‐west pattern of dispersal, associated with a late Miocene origin for cave crickets and an early Miocene origin for Calathus (median age 16–20 Ma).…”

“…To better understand the evolution of MB biota, historical biogeography and diversification-rate analyses may help decipher complex patterns by assessing the role of past geological and climate changes (Condamine et al, 2012;Drummond et al, 2012). Integrative biogeographical and diversification studies on the MB are, however, scarce (Allegrucci et al, 2012;Buerki et al, 2012;Ruiz et al, 2012).…”

The tiger beetles (Coleoptera, Carabidae, Cicindelinae) of Israel and adjacent lands

“…By analogy with other groups of carabid beetles (Kataev 1984, 2011; Casale and Vigna Taglianti 1999; Ruiz et al 2012), we can assume that the genesis of the ancestral taxa of most recent cicindelids in the Mediterranean region began in late Paleogene – early Neogene (on the border of Oligocene – Miocene). According to data of DNA analysis the divergence processes of taxa of subtribe Cicindelina began ca.…”

Diversification of montane species via elevation shifts: the case of the Kaçkar cricketPhonochorion(Orthoptera)

“…We are aware of only four studies within Anatolia all from western Turkey which show clear patterns of introgession between lineages: introgression between two parapatric subspecies of newts (Nadachowska and Babik ), Carabidae beetles (Ruiz et al. ), shrews (Dubey et al. ) and between two species of pine processionary moths (İpekdal ).…”

“…We are aware of only four studies within Anatolia all from western Turkey which show clear patterns of introgession between lineages: introgression between two parapatric subspecies of newts (Nadachowska and Babik 2009), Carabidae beetles (Ruiz et al 2012), shrews (Dubey et al 2008) and between two species of pine processionary moths ( _ Ipekdal 2012). However, only Nadachowska and Babik (2009) gave evidence for a model of divergence with gene flow, and it was not apparent in the other studies if divergence proceeded under the influence of gene flow or whether patterns just reflected past mtDNA introgression.…”