A tale of migrations from east to west: the Irano‐Turanian floristic region as a source of Mediterranean xerophytes. (8th August 2013)

• Record Type: Journal Article
• Authors: Manafzadeh, Sara; Salvo, Gabriele; Conti, Elena; Ebach, Malte
• Is Part Of: Journal of biogeography. Volume 41:Number 2(2014:Feb.)
• Page Start: 366
• Page End: 379
• Publication Date: 2013-08-08
• Subjects: Biogeography -- Periodicals; 578.09
• DOI: 10.1111/jbi.12185
• Languages: English
• ISSNs: 0305-0270

Abstract

<abstract abstract-type="main" id="jbi12185-abs-0001"> <title>Abstract</title> <sec id="jbi12185-sec-0001" sec-type="section"> <title>Aim</title> <p>The Irano‐Turanian (IT) floristic region is characterized by high levels of endemicity. Despite its potential role as a cradle of xerophytic taxa for neighbouring areas, its biogeographical history remains poorly studied. <italic>Haplophyllum</italic>, a diagnostic element of the IT region, was used as a model to discriminate between alternative biogeographical scenarios for the evolution of the region and, more specifically, to investigate whether it served as a source of xerophytes for the colonization of the Mediterranean Basin.</p> </sec> <sec id="jbi12185-sec-0002" sec-type="section"> <title>Location</title> <p>Irano‐Turanian floristic region (Central Asia and West Asiatic areas) and Mediterranean floristic region (western and eastern parts of the Mediterranean Basin).</p> </sec> <sec id="jbi12185-sec-0003" sec-type="section"> <title>Methods</title> <p>Three chloroplast DNA regions were sequenced in 77 accessions of <italic>Haplophyllum</italic> and 37 accessions from other subfamilies of Rutaceae. To elucidate the temporal and spatial evolution of <italic>Haplophyllum</italic> in the IT and Mediterranean regions, we performed Bayesian molecular dating analyses with four fossil constraints and ancestral range reconstructions, respectively.</p> </sec> <sec id="jbi12185-sec-0004" sec-type="section"> <title>Results</title> <p>Our molecular dating and ancestral area reconstruction analyses suggest that <italic>Haplophyllum</italic> originated in the Central Asian part of the IT region during the early Eocene and started to diversify <italic>in situ</italic> during the early Oligocene, soon after the vanishing of the Tethys Ocean. Our results further imply that <italic>Haplophyllum</italic> later invaded the eastern Mediterranean Basin in the middle‐to‐late Miocene, concomitantly with the Paratethys Salinity Crisis and rapid palaeobiogeographical changes in the proto‐Mediterranean. Finally, <italic>Haplophyllum</italic> diversified in the western Mediterranean in the early Pliocene at the end of the Messinian Salinity Crisis.</p> </sec> <sec id="jbi12185-sec-0005" sec-type="section"> <title>Main conclusions</title> <p>The IT floristic region can serve as a 'donor' of xerophytic taxa to 'recipient' neighbouring regions, including the Mediterranean floristic region. The climatic/geological processes during the Miocene–Pliocene, by increasing aridity and topographic heterogeneity, facilitated range shifts and allopatric speciation in the region.</p> </sec> </abstract>