A journey on plate tectonics sheds light on European crayfish phylogeography

Abstract

Crayfish can be used as model organisms in phylogeographic and divergence time studies if reliable calibrations are available. This study presents a comprehensive investigation into the phylogeography of the European stone crayfish ( Austropotamobius torrentium ) and includes samples from previously unstudied sites. Two mitochondrial markers were used to reveal evolutionary relationships among haplogroups throughout the species’ distributional range and to estimate the divergence time by employing both substitution rates and geological calibration methods. Our haplotype network reconstruction and phylogenetic analyses revealed the existence of a previously unknown haplogroup distributed in Romania's Apuseni Mountains. This haplogroup is closely related to others that are endemic in the Dinarides, despite their vast geographical separation (~600 km). The separation is best explained by the well‐dated tectonic displacement of the Tisza–Dacia microplate, which started in the Miocene (~16 Ma) and possibly carried part of the A. torrentium population to the current location of the Apuseni Mountains. This population may thus have been isolated from the Dinarides for a period of ca. 11 m.y. by marine and lacustrine phases of the Pannonian Basin. The inclusion of this geological event as a calibration point in divergence time analyses challenges currently accepted crayfish evolutionary time frames for the region, constraining the evolution of this area's crayfish to a much earlier date. We discuss why molecular clock calibrations previously employed to date European crayfish species divergences should therefore be reconsidered.

Morphological diversity of the stone crayfish − traditional and geometric morphometric approach

“…2012; Perry et al, 2013;Rudolph et al, 2016) or genetic background (Sint et al, 2007;Cataudella et al, 2010;Maguire et al, 2017;Pârvulescu, 2019) or probably combination of both (Baric et al, 2005a(Baric et al, , 2005bBertocchi et al et al, 2008;Mathews et al, 2008;Helms et al, 2015;Berger et al, 2017). Former molecular phylogenetic and phylogeographic research of the stone crayfish based on the mtDNA revealed existence of at least seven (Klobučar et al, 2013) or eight (Pârvulescu et al, 2019) highly divergent monophyletic phylogroups within A. torrentium, with the highest genetic diversity recorded in the north-central Dinarids in Croatia. Especially high distances were obtained for phylogroups ZV, GK, ŽPB and LD.…”

“…Previous molecular-phylogenetic research based on mtDNA by Trontelj et al (2005) indicated that the stone crayfish should be considered a species complex. Later, Klobučar et al (2013) discovered the existence of at least seven divergent monophyletic phylogroups within A. torrentium, with the highest genetic diversity recorded in the Dinaric region of Croatia, while recently Pârvulescu et al (2019) described another phylogroup endemic to the Romanian Apuseni region. Moreover, latest analyses of meristic and morphometric features of several stone crayfish populations, belonging to different phylogroups, indicated their significant differences and point to necessity of additional analyses that would cover bigger sample size and wider area (Maguire et al, 2017).…”

“…Moreover, latest analyses of meristic and morphometric features of several stone crayfish populations, belonging to different phylogroups, indicated their significant differences and point to necessity of additional analyses that would cover bigger sample size and wider area (Maguire et al, 2017). Following that idea, a new Austropotamobius crayfish species was just described (Pârvulescu et al, 2019).…”

New insights into the genetic diversity of the stone crayfish: taxonomic and conservation implications

“…1 ) that are related to karstic formations [ 1 , 2 ]. The species exhibits high genetic diversity represented by the eight distinct mtDNA lineages/phylogroups discovered so far [ 3 – 5 ].

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“…1 Geographical distribution of different A. torrentium mtDNA phylogroups in Europe produced in ArcGIS 10.3 program package and finished in the program Inscape 1.0 by authors of this study. Symbols used on the map: dots represent samples from previous research [ 3 – 5 ], and triangles samples from this study. Colours depict mitochondrial phylogroups: black—central and south-eastern Europe (CSE), blue—Gorski Kotar (GK), purple—Lika and Dalmatia (LD), orange—Žumberak, Plitvice and Bjelolasica (ŽPB), pink—southern Balkans (SB), green—Banovina (BAN), red—Zeleni Vir (ZV), gray—Apuseni Mountain (APU) and turquoise blue—Kordun (KOR), new phylogroup discovered in the present study.…”