Preliminary study of the canids from the Lower Pleistocene site of Tsiotra Vryssi (Mygdonia basin, Greece)

Abstract

The Lower Pleistocene site of Tsiotra Vryssi (TSR), discovered in 2014, is located in the south-eastern part of the Mygdonia Basin (northern Greece) and belongs to the upper part of the Gerakarou Formation (Konidaris et al., 2015). The site has revealed a rich late Villafranchian fauna, which is dated between 1.78 and ~1.5 Ma (Konidaris et al., 2021). Among the faunal assemblage, canids are well-represented and their cranial, mandibular and dental material consists of 17 specimens (excavation seasons 2014–2019) stored at the Museum of Geology, Palaeontology and Palaeoanthropology of the Aristotle University of Thessaloniki (LGPUT). The aim of the present study is to provide preliminary results on their taxonomy based on their morphological and metrical comparison with Early Pleistocene European taxa known from the literature.The TSR material comprises medium- and large-sized canids, which are consistent morphologically and metrically with an attribution to Canis. Several Canis species are documented in Europe during the late Villafranchian. Canis etruscus and C. arnensis were possibly already present slightly before the beginning of the late Villafranchian, and they are best recorded in several Italian localities dated to 2.0–1.8 Ma (e.g., Cherin et al., 2014; Bartolini Lucenti and Rook, 2016). Canis etruscus in particular is suggested as the possible ancestor of the more advanced C. mosbachensis and subsequently of the modern wolf (e.g., Sotnikova and Rook, 2010). Canis accitanus from Fonelas-P1 (~2.0 Ma, Spain), is a debated taxon; Brugal and Boudadi-Maligne (2011) suggest that it rather belongs to C. arnensis, whereas Martínez-Navarro et al. (2021) propose that it could be part of the intraspecific variability of C. etruscus, which is also present at the site. Recent discoveries have furthermore revealed new species. Canis borjgali from Dmanisi (~1.8 Ma, Georgia) shares morphological features withC. mosbachensis, therefore this species was proposed as a closer ancestor of the C. lupus lineage instead of the more primitive C. etruscus (Bartolini Lucenti et al., 2020). Canis orcencis from Venta Micena (~1.6 Ma, Spain) resembles C. mosbachensis and C. apolloniensis from Apollonia-1 (~1.3–1.0 Ma, Greece; Koufos, 2018), but shows some distinct morphological traits (Martínez-Navarro et al., 2021). According to Madurell-Malapeira et al. (2022), C. orcencis and C. apolloniensis could be ascribed to C. mosbachensis, which successfully dispersed in Europe during the late Early–Middle Pleistocene, until the appearance of C. lupus. Regarding the large-sized European canids, the hypercarnivorous Canis (Xenocyon) falconeri is best recorded in Upper Valdarno (Ialy) and Fonelas-P1, while recent findings reveal an earlier record in the middle Villafranchian (Bartolini Lucenti and Spassov, 2022). This taxon was replaced by the more advanced Canis (Xenocyon) lycaonoides, which is found in many European localities (e.g., Dmanisi, Pirro Nord, Apollonia-1), usually along with a medium-sized Canis (e.g., Bartoloni Lucenti et al., 2021).