Early Miocene squamate assemblage from the Mokrá-Western Quarry (Czech Republic) and its palaeobiogeographical and palaeoenvironmental implications Author Ivanov, Martin Author Čerňanský, Andrej Author Bonilla-Salomón, Isaac Author Luján, Àngel Hernández text Geodiversitas 2020 2020-08-28 42 20 343 376 journal article 8562 10.5252/geodiversitas2020v42a20 ad4dbfb6-14ce-48e2-8fe9-99fa26a9bcf4 1638-9395 4447563 urn:lsid:zoobank.org:pub:8FF2A078-CE45-4BF1-A681-00136F57375E LACERTIDAE indet. tooth morphotype 2 ( Fig. 2H ) MATERIAL. — MWQ, early Miocene, Burdigalian, Orleanian, MN 4: 1/2001 Turtle Joint: One left dentary (Pal. 1401). DESCRIPTION Dentary The description is based on the fragment of the anterior half of a left dentary. The element bears ten tooth positions (four teeth are still attached). The dental crest is high, and the teeth extend above it only in a quarter of their total height. The subdental shelf ( sensu Rage & Augé, 2010 ) is robust, being only slightly concave in this section. Meckel’s groove is open, narrow in the preserved section, but gradually widening posteriorly. The lateral surface of the bone is smooth, pierced by several labial foramina. Dentition The implantation is pleurodont. Teeth are tall and robust. The interdental gaps are small – the size of the gap forms approximately only a 1/4 of the mesiodistal length of the tooth neck. The tooth crowns are bicuspid, with a dominant distal (central) cusp and a smaller mesial cusp. The lingual portion of the crowns bears vertical striations. The striae are almost parallel, and their number is around six. In medial aspect, the tooth necks are more or less as wide as the tooth crowns, in some cases gradually narrowing slightly ventrally. The necks appear slightly more swollen lingually if compared to the tooth crowns. The central part of the tooth base is pierced by a resorption pit. REMARKS Although the dentary described here possesses some similarities with the above described lacertid material, e.g. bicuspid teeth, several important differences can be observed: 1) large size; 2) the high dental crest; 3) small interdental gaps; 4) more robust teeth; and 5) low number of lingual striae on the tooth crowns. Because not all of those differences can be explained by ontogenetic changes, we suggest the presence of at least two lacertid taxa in MWQ.