Lacertidae Oppel 1811

LACERTIDAE indet. (Fig. 2A, B) MATERIAL. — MWQ, early Miocene, Burdigalian, Orleanian, MN 4: 2/2003 Reptile Joint: one left frontal (Pal. 1565). DESCRIPTION Frontal Only the anterior portion of the left frontal is preserved. The dorsal surface bears two osteodermal shields fused to the bone. The main region is occupied by the frontal shield, whereas the prefrontal shield is located in the anterolateral section. The dorsal regions of the shields are sculptured. The sculpture consists of irregularly distributed pits and several connected ridges. Both shields are separated one from another by a slightly rounded (medially convex) sulcus, which runs posterolaterally to the lateral margin of the bone. The anterior termination of the frontal is divided into larger lateral process and slightly smaller medial process. Between them, a wedge-shaped facet for the nasal is present, forming a bony septum. The facet for the posterodorsal termination of the maxillary nasal process is located lateral to the lateral process, however, this region is damaged. The medial margin, which forms a contact with the right frontal, is straight. On the internal surface, the frontal cranial ridge can be observed. This portion is unfortunately badly preserved – its section that would form an anteroventrally oriented subolfactory process is broken off. LACERTIDAE indet. tooth morphotype 1 (Fig. 2 C-G) MATERIAL. — MWQ, early Miocene, Burdigalian, Orleanian, MN 4: 1/2001 Turtle Joint: One left dentary (Pal. 1400). 2/2003 Reptile Joint: one right maxilla (Pal. 1566), 3 dentaries, 1 left + 2 right (Pal. 1567-1569). DESCRIPTION Maxilla Only a small fragment of the right maxilla is preserved (Fig. 2C, D). This portion bears two teeth, which are bordered dorsally by the supradental shelf. The lateral surface is pierced by a large labial foramen. Dentary The description is based on two fragments – one represents a left dentary, whereas the second is a right dentary. The left dentary fragment (Fig. 2E, F) bears four tooth positions (two teeth are still attached). The right dentary (Fig. 2G) exhibits five and half tooth positions (four teeth are still attached, but the tooth crown of one tooth is broken off). The dental crest is low, and teeth exceed it by 1/2 of their height. The subdental shelf (sensu Rage & Augé 2010) is well developed, robust. However only its short portion is preserved. It gradually becomes thinner posteriorly (this can be observed mainly in the right dentary fragment), partly as a result of the presence of the facet for the splenial, situated on its ventral margin. The shelf forms the dorsal roof of the Meckel’s groove, which is open but narrow. The lateral surface of the bone is smooth. In the preserved section, it is pierced by two labial foramina located slightly above the mid-section of the bone. Dentition The implantation is pleurodont.Teeth are high. The interdental gaps are large – the size of the gap forms approximately the 1/2 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 distal cusp is pointed in most cases and slightly directed posterolingually. The lingual portion of the crowns bears vertical striations. The striae are almost parallel, and their number is around ten. The tooth necks are slightly expanded lingually and they appear lightly more swollen if compared to the tooth crowns. The central part of the tooth base is pierced by a small resorption pit. REMARKS The maxilla and dentary have identical tooth morphology and thus can be attributed to the single taxon. Several features in the material from Mokrá described here resemble Lacerta poncenatensis: 1) the presence of robust bicuspid teeth; 2) the wide interdental gaps; and 3) the low dental crest. This taxon was originally described by Müller (1996) from the French locality of Poncenat (early Miocene, MN 2a). Later, it was also recognized in Germany (Čerňanský et al. 2015; early Miocene, MN 2) and Austria (Čerňanský 2016; early Miocene, MN 4). However, the fragmentary nature of the Mokrá material does not allow confident alpha taxonomy. 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. Unranked clade AMPHISBAENIA Gray, 1844 AMPHISBAENIA indet. (Fig. 3) Blanus sp. – Ivanov et al. 2006: 229, table 2. MATERIAL. — MWQ, early Miocene, Burdigalian, Orleanian, MN 4: 2/2003 Reptile Joint: One trunk vertebra (Pal. 1570). DESCRIPTION Trunk vertebra A single trunk vertebra is preserved. It is small in size. A neural spine is absent, and the dorsal portion of the neural arch forms a median edge. In lateral view, the synapophysis is simple and large. The posterior portion of the neural arch is fused with the postzygapophyses, forming the dorsal roof (or lamina) between the left and right postzygapophyses. The neural canal is subtriangular with distinct lateral sinuses. The interzygapophyseal constriction is distinct and it occurs in the anterior half of the anteroposterior vertebral length. The dorsally tilted prezygapophyseal articular facets have an elliptical shape. A zygosphene is absent. The ventral side of the depressed centrum is flat, pierced by a pair of large subcentral foramina in the anterior 1/3 of the anteroposterior length. The lateral margins (subcentral ridges) are roughly parallel in ventral aspect. No constriction is developed at the base of the damaged condyle. The postzygapophyseal articular facets are oval and slightly enlarged posteriorly. The cotyle is distinctly laterally enlarged. REMARKS The vertebra described here can be attributed to Amphisbaenia based on the following combination of features (see Estes 1983): 1) the depressed centrum, having a flat ventral surface; 2) roughly parallel lateral margins in ventral aspect; 3) massive synapophyses; 4) the absence of a zygosphene (enabling distinction of amphisbaenians from scolecophidian snakes (Estes 1983; Rage 1984); and 5) the sinusoidal neural arch lacking a neural spine. Family level allocation of an isolated vertebra is limited by a lack of clear diagnostic features for identification (Estes 1983; Augé 2005, 2012; Georgalis et al. 2016b).We can exclude rhineurids, which have a denticulate vertebral posterior margin. The same feature can be observed in trogonophiids as well (Kearney 2003; Augé 2012; Čerňanský et al. 2016a). Based on the geographical position of the locality and the age of the sediments, this vertebra most likely represents a blanid taxon. According to cranial elements, amphisbaenians reported from the Central European late Oligocene and Miocene localities are almost exclusively identified as belonging to the clade Blanidae (Roček 1984; Schleich 1988; Čerňanský & Venczel 2011; Čerňanský et al. 2016a). The morphology and dimensions of the vertebra described here are very similar to those of trunk vertebra of Blanus gracilis Roček, 1984 reported from the Czech early Miocene (MN 4b) Dolnice site (Roček 1984: 5, table 16). LACERTIDAE indet. tooth morphotype 1 (Fig. 2 C-G) MATERIAL. — MWQ, early Miocene, Burdigalian, Orleanian, MN 4: 1/2001 Turtle Joint: One left dentary (Pal. 1400). 2/2003 Reptile Joint: one right maxilla (Pal. 1566), 3 dentaries, 1 left + 2 right (Pal. 1567-1569). DESCRIPTION Maxilla Only a small fragment of the right maxilla is preserved (Fig. 2C, D). This portion bears two teeth, which are bordered dorsally by the supradental shelf. The lateral surface is pierced by a large labial foramen. Dentary The description is based on two fragments – one represents a left dentary, whereas the second is a right dentary. The left dentary fragment (Fig. 2E, F) bears four tooth positions (two teeth are still attached). The right dentary (Fig. 2G) exhibits five and half tooth positions (four teeth are still attached, but the tooth crown of one tooth is broken off). The dental crest is low, and teeth exceed it by 1/2 of their height. The subdental shelf (sensu Rage & Augé 2010) is well developed, robust. However only its short portion is preserved. It gradually becomes thinner posteriorly (this can be observed mainly in the right dentary fragment), partly as a result of the presence of the facet for the splenial, situated on its ventral margin. The shelf forms the dorsal roof of the Meckel’s groove, which is open but narrow. The lateral surface of the bone is smooth. In the preserved section, it is pierced by two labial foramina located slightly above the mid-section of the bone. Dentition The implantation is pleurodont.Teeth are high. The interdental gaps are large – the size of the gap forms approximately the 1/2 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 distal cusp is pointed in most cases and slightly directed posterolingually. The lingual portion of the crowns bears vertical striations. The striae are almost parallel, and their number is around ten. The tooth necks are slightly expanded lingually and they appear lightly more swollen if compared to the tooth crowns. The central part of the tooth base is pierced by a small resorption pit. REMARKS The maxilla and dentary have identical tooth morphology and thus can be attributed to the single taxon. Several features in the material from Mokrá described here resemble Lacerta poncenatensis: 1) the presence of robust bicuspid teeth; 2) the wide interdental gaps; and 3) the low dental crest. This taxon was originally described by Müller (1996) from the French locality of Poncenat (early Miocene, MN 2a). Later, it was also recognized in Germany (Čerňanský et al. 2015; early Miocene, MN 2) and Austria (Čerňanský 2016; early Miocene, MN 4). However, the fragmentary nature of the Mokrá material does not allow confident alpha taxonomy. 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. Unranked clade AMPHISBAENIA Gray, 1844 AMPHISBAENIA indet. (Fig. 3) Blanus sp. – Ivanov et al. 2006: 229, table 2. MATERIAL. — MWQ, early Miocene, Burdigalian, Orleanian, MN 4: 2/2003 Reptile Joint: One trunk vertebra (Pal. 1570). DESCRIPTION Trunk vertebra A single trunk vertebra is preserved. It is small in size. A neural spine is absent, and the dorsal portion of the neural arch forms a median edge. In lateral view, the synapophysis is simple and large. The posterior portion of the neural arch is fused with the postzygapophyses, forming the dorsal roof (or lamina) between the left and right postzygapophyses. The neural canal is subtriangular with distinct lateral sinuses. The interzygapophyseal constriction is distinct and it occurs in the anterior half of the anteroposterior vertebral length. The dorsally tilted prezygapophyseal articular facets have an elliptical shape. A zygosphene is absent. The ventral side of the depressed centrum is flat, pierced by a pair of large subcentral foramina in the anterior 1/3 of the anteroposterior length. The lateral margins (subcentral ridges) are roughly parallel in ventral aspect. No constriction is developed at the base of the damaged condyle. The postzygapophyseal articular facets are oval and slightly enlarged posteriorly. The cotyle is distinctly laterally enlarged. REMARKS The vertebra described here can be attributed to Amphisbaenia based on the following combination of features (see Estes 1983): 1) the depressed centrum, having a flat ventral surface; 2) roughly parallel lateral margins in ventral aspect; 3) massive synapophyses; 4) the absence of a zygosphene (enabling distinction of amphisbaenians from scolecophidian snakes (Estes 1983; Rage 1984); and 5) the sinusoidal neural arch lacking a neural spine. Family level allocation of an isolated vertebra is limited by a lack of clear diagnostic features for identification (Estes 1983; Augé 2005, 2012; Georgalis et al. 2016b).We can exclude rhineurids, which have a denticulate vertebral posterior margin. The same feature can be observed in trogonophiids as well (Kearney 2003; Augé 2012; Čerňanský et al. 2016a). Based on the geographical position of the locality and the age of the sediments, this vertebra most likely represents a blanid taxon. According to cranial elements, amphisbaenians reported from the Central European late Oligocene and Miocene localities are almost exclusively identified as belonging to the clade Blanidae (Roček 1984; Schleich 1988; Čerňanský & Venczel 2011; Čerňanský et al. 2016a). The morphology and dimensions of the vertebra described here are very similar to those of trunk vertebra of Blanus gracilis Roček, 1984 reported from the Czech early Miocene (MN 4b) Dolnice site (Roček 1984: 5, table 16). 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. Unranked clade AMPHISBAENIA Gray, 1844 AMPHISBAENIA indet. (Fig. 3) Blanus sp. – Ivanov et al. 2006: 229, table 2. MATERIAL. — MWQ, early Miocene, Burdigalian, Orleanian, MN 4: 2/2003 Reptile Joint: One trunk vertebra (Pal. 1570). DESCRIPTION Trunk vertebra A single trunk vertebra is preserved. It is small in size. A neural spine is absent, and the dorsal portion of the neural arch forms a median edge. In la
Published as part of Ivanov, Martin, Čerňanský, Andrej, Bonilla-Salomón, Isaac & Luján, Àngel Hernández, 2020, Early Miocene squamate assemblage from the Mokrá-Western Quarry (Czech Republic) and its palaeobiogeographical and palaeoenvironmental implications, pp. 343-376 in Geodiversitas 42 (20) on pages 346-349, DOI: 10.5252/geodiversitas2020v42a20, http://zenodo.org/record/4447563
{"references":["RAGE J. - C. & AUGE M. L. 2010. - Squamate reptiles from the middle Eocene of Lissieu (France). A landmark in the middle Eocene of Europe. Geobios 43 (2): 253 - 268. https: // doi. org / 10.1016 / j. geobios. 2009.08.002","MULLER J. 1996. - Eine neue Art der Echten Eidechsen (Reptilia: Lacertilia: Lacertidae) aus dem Unteren Miozan. Mainzer Geowissenschaftliche Mitteilungen 25: 79 - 88.","CERNANSKY A., RAGE J. C. & KLEMBARA J. 2015. - The Early Miocene squamates of Amoneburg (Germany): the first stages of modern squamates in Europe. The Journal of Systematic Palaeontology 13 (2): 97 - 128. https: // doi. org / 10.1080 / 14772019.20 14.897266","IVANOV M., MUSIL R. & BRZOBOHATY R. 2006. - Terrestrial and Marine Faunas from the Miocene Deposits of the Mokra Plateau (Drahany Upland, Czech Republic) - Impact on Palaeogeography. Beitrage zur Palaontologie 30: 223 - 239.","ESTES R. 1983. - Sauria Terrestria. Part 10 A, in WELLNHOFER P. (ed.), Handbuch der Palaoherpetologie (Encyclopedia of Paleoherpetology). Gustav Fischer Verlag, Stuttgart, 249 p.","AUGE M. 2005. - Evolution des lezards du Paleogene en Europe. Museum national d'Histoire naturelle, Paris, 369 p. (Memoires du Museum national d'Histoire naturelle; 192).","AUGE M. 2012. - Amphisbaenians from the European Eocene: a biogeographical review, in LEHMANN T. & SCHAAL S. F. K. (ed.), Messel and the Terrestrial Eocene. Proceedings of the 22 nd Senckenberg Conference. Palaeobiodiversity and Palaeoenvironments 92 (4): 425 - 443. https: // doi. org / 10.1007 / s 12549 - 012 - 0104 - 6","GEORGALIS G. L., VILLA A., VLACHOS E. & DELFINO M. 2016 b. - Fossil amphibians and reptiles from Plakias, Crete: a glimpse into the earliest late Miocene herpetofaunas of southeastern Europe. Geobios 49 (6): 433 - 444. https: // doi. org / 10.1016 / j. geobios. 2016.09.004","KEARNEY M. 2003. - Systematics of the Amphisbaenia (Lepidosauria: Squamata) based on morphological evidence from recent and fossil forms. Herpetological Monographs 17 (1): 1 - 74. http: // doi. org / b 9 r 92 g","CERNANSKY A., KLEMBARA J. & MULLER J. 2016 a. - The new rare record of the late Oligocene lizards and amphisbaenians from Germany and its impact on our knowledge of the European terminal Palaeogene. Palaeobiodiversity and Palaeoenvironment 96 (4): 559 - 587. https: // doi. org / 10.1007 / s 12549 - 015 - 0226 - 8","ROCEK Z. 1984. - Lizards (Reptilia: Sauria) from the Lower Miocene locality Dolnice (Bohemia, Czechoslovakia). Rozpravy Ceskoslovenske Akademie Ved, Rada Matematickych a Prirodnich Ved 94: 1 - 69.","SCHLEICH H. H. 1988. - Neue Reptilienfunde aus dem Tertiar Deutschlands 8. Palaeoblanus tobieni n. gen., n. sp. - neue Doppelschleichen aus dem Tertiar Deutschlands. Palaontologische Zeitschrift 62 (1 / 2): 95 - 105.","CERNANSKY A. & VENCZEL M. 2011. - An amphisbaenid reptile (Squamata, Amphisbaenidae) from the Lower Miocene of Northwest Bohemia (MN 3, Czech Republic). Neues Jahrbuch fur Geologie und Palaontologie-Abhandlungen 260 (1): 73 - 77. https: // doi. org / 10.1127 / 0077 - 7749 / 2011 / 0129"]}