Fig 1.
(a), Fossil locality marked by red contoured circle in a relation to the Euphrates-Tigris and Araxes-Kura water basins. (b), map showing the fossil locality marked by red contoured circle. Map data: Fig 1A and 1B is redrawn and modified from U. S. Geological Survey, CC BY 4.0.
Fig 2.
Geographical overview of the drainage systems of Western Asia and the Ponto-Caspian regions (Euphrates-Tigris, Araxes-Kura).
Red star (1) indicates the position of the Ҫevırme locality. The red circle shows the possible extension of palaeolake system of the Armenian Highland. The arrows show the late distribution of the recorded fossil Capoeta species into the different water basins due to the tectonic disruption of the Lake system during the Pliocene uplift period. The two already known late Miocene fossil sites Kisatibi (red star 2) and Jradzor (red star 3) are included as well. Map data: Fig 2 is redrawn and modified from U. S. Geological Survey CC BY 4.0.
Fig 3.
Phylogeny of the genus Capoeta.
(a), distinguished clades within the genus Capoeta (Luciobarbus suquincunciatus is the sister clade) (Levin et al., 2012). The clade diagnostic shape classes of recorded clades within the fossil material (see, Ayvazyan et al. 2018; Fig 7) are given in capital letters included 3D images of teeth of Capoeta as well as the a2 tooth of L. subquincunciatus. The monophyletic Anatolia-Iranian/Aralo-Caspian/sieboldi clade, for which we propose a species flock model of evolution, is marked by red colour. (b), the location of Capoeta clade within phylogenetic tree based on the molecular genetic analysis (Levin et al., 2012).
Fig 4.
Sedimentary succession of the Işιklar Formation at the fossil site.
Çevirme (Erzurum Province, Tekman district) according to Sickenberg (1975).
Fig 5.
Isolated fossil pharyngeal teeth from the early Pliocene locality Ҫevırme (Erzurum Province, Tekman district).
(a-e), species/clade diagnostic shape classes: a, shape class "A" characteristic of C. umbla (BGR Ҫevırme 1). (b), shape class "R", characteristic of C. sieboldi (BGR Ҫevırme 3). (c-d), shape class "J", characteristic of C. baliki (BGR Ҫevırme 4, 5). (e), clade diagnostic shape class "M", characteristic of Aralo-Caspian clade of genus Capoeta (C. sevangi and C. capoeta) BGR Ҫevırme 23). (f-k), genus diagnostic shape class "C" (BGR Ҫevırme 24, 25, 26, 27, 28, 29). (l-s), common shape classes shared by different species. (l-n), shape class "B" (BGR Ҫevırme 155, 156, 157). (o-q), shape class "F" (BGR Ҫevırme 195, 196, 197). (r-s), shape class "H" (BGR Ҫevırme 226, 227). (t), not identified, possibly tooth pathology (BGR Ҫevırme 237). (u), not identified (BGR Ҫevırme 238).
Table 1.
Isolated fossil pharyngeal teeth (n = 247) and identified shape classes in the studied fossil material.
Table 2.
Comparative material of extant Capoeta species.
Fig 6.
Examples to describe the isolated pharyngeal teeth based on the shape characters and shape classes.
(a), shape class "M", b2 tooth of extant C. capoeta. (b), shape characters (α5β4) defining shape class "M". (c), shape class "D", a2 tooth of extant C. sieboldi. (d), shape characters (α4β7) defining shape class "D". Details of shape characters α and β see Ayvazyan et al. 2018. The scales are not given to avoid scaling up of the figures.
Fig 7.
Additional morphological characters (besides the shape characters (αβ) in fossil and extant pharyngeal teeth (not to scale).
(a), Capoeta sp., b3 tooth (extant) (SAPM-PI-00719, SNSB). (b), C. trutta, a5 tooth (extant) (SAPM-PI-02908, SNSB). (c-d), isolated fossil pharyngeal teeth (identified as shape class "C" and "F" respectively) (BGR 6, 16). (e), isolated fossil pharyngeal tooth (BGR 5). (f), C. capoeta, b2 tooth (extant) (GPIT-OS-00860a), both are identified as shape class "M". The ruptures of grinding surface are marked by red arrows (a, b, c, d) and an example of very similar tooth morphology in fossil (e) and extant (f) isolated pharyngeal teeth.
Fig 8.
Hypothetical evolutionary stages of the palaeolake system of Armenian Highland since latest Miocene.
Three main stages are suggested (marked by blueish colours): formation, maximum of lake expansion, decay and fully development of present-day drainage system. The monophyletic clade of recorded species within the fossil material shows the presence of the species flock of Capoeta at 4 Ma ago in palaeolake system of Armenian Highland.