# Diversity in a greenhouse world: herpetofauna from the late Eocene (MP 17A) of La Bouffie, Quercy Phosphorites (Lot, SW France)

Alfred Lemierre, Georgios L Georgalis

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Alfred Lemierre, Georgios L Georgalis. Diversity in a greenhouse world: herpetofauna from the late Eocene (MP 17A) of La Bouffie, Quercy Phosphorites (Lot, SW France). Swiss Journal of Palaeontology, 2025, 144 (1), pp.40. 10.1186/s13358-025-00370-9. hal-05316813

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# Diversity in a greenhouse world: herpetofauna from the late Eocene (MP 17A) of La Bouffie, Quercy Phosphorites (Lot, SW France)

Alfred Lemierre<fnref n="1" />* and Georgios L. Georgalis<fnref n="2" />

**Abstract**

The Quercy Phosphorites area (Southwestern France) provides more than 200 fossiliferous localities, ranging from the early Eocene to the Early Miocene. These localities document a rich and diverse continental fauna and highlight a massive turnover in vertebrates around the Eocene–Oligocene transition. Among them, the locality of La Bouffie, from the early late Eocene (MP 17A) has yielded a diverse herpetofauna, including rare taxa for Europe (e.g., Tupinambinae). Unfortunately, most of the herpetofauna has never been described nor illustrated, leaving uncertainties regarding its true diversity. We here describe “forgotten” and undescribed specimens from La Bouffie, that pertain to pyxicephalid anurans, and gekkotan, lacertid, amphisbaenian, pleurodontan, glyptosaurid, anguine, helodermatid and palaeovaranid lizards. Among them, five taxa are identified for the first time in La Bouffie, including two new genera and species: *Phosphoriguana peritechne* gen. et sp. nov. (?Pleurodonta) and *Cadurcopanoplos vaylatsensis* gen. et sp. nov. (Glyptosauridae). *Phosphoriguana peritechne* gen. et sp. nov. represents the fourth pleurodontan genus from the late Eocene of Europe, highlighting the diversity of the clade on the continent prior to the “Grande Coupure”. The glyptosaurine glyptosaurid *Cadurcopanoplos vaylatsensis* gen. et sp. nov. represents only the second late Eocene glyptosaurine from Europe, differing from *Placosaurus* in having a cranial osteoderm pattern reminiscent of early Eocene glyptosaurines, like *Sullivanosaurus*; it therefore suggests a higher diversity of this group in the late Eocene. A review of the herpetofauna of La Bouffie identifies at least 18 illustrated and formally described taxa, while other 8 need to be properly reassessed, as the latter have only been so far briefly mentioned. This renders La Bouffie one of the most diverse late Eocene localities in Europe.

**Keywords** Quercy Phosphorites, Herpetofauna, Eocene, New taxa, Europe

Handling editor: Daniel Marty

*Correspondence:

Alfred Lemierre
alfred.lemierre@gov.ab.ca

**Introduction**

The Quercy Phosphorites area provides more than 200 fossiliferous localities in southwestern France (Pélissié et al., 2021). Age estimates range from the early Eocene to the Early Miocene, but most fossiliferous localities are concentrated around the late Eocene–early Oligocene (Pélissié et al., 2021). The herpetofauna identified in the Phosphorites is diverse (Rage, 2006) ranging from pyxicephalid anurans to large constrictor snakes (Filhol, 1876, 1877; Rochebrune, 1880, 1884; Zittel, 1887–1890; De Stefano, 1903, 1905; Leenhardt, 1926;

<figure><img src="image_3.png" /></figure>

<footnote n="1">¹ Royal Tyrrell Museum of Palaeontology, Box 7500, Drumheller, Alberta T0J 0Y0, Canada</footnote>

<footnote n="2">² Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Slawkowska 17, 31-016 Kraków, Poland</footnote>
Hoffstetter, 1942, 1946, 1957; Hoffstetter & Rage, 1972; Rage, 1974, 1978, 1988, 2006, 2016; Broin, 1977; Augé, 1987, 1988, 1992, 2001, 2005; Roček & Lamaud, 1995; Augé & Rage, 1995; Augé & Smith, 1997; Szyndlar & Rage, 2003; Augé & Sullivan, 2006; Claude & Tong, 2006; Sullivan & Augé, 2006; Rage & Roček, 2007; Čerňanský & Augé, 2013; Tissier et al., 2016; Georgalis, 2017, 2025; Augé & Brizuela, 2020; Georgalis et al., 2021a, 2023 2021c; Lemierre et al., 2021; Čerňanský, 2023; Čerňanský et al., 2023a, 2025, 2023c). The locality of La Bouffie has been studied since the early 1980s (Crochet et al., 1981) and has yield a diverse fauna of vertebrates, ranging from primates to parrots (Godinot & Dagosto, 1983; Maitre, 2014; Maitre et al., 2008; Mayr et al., 2024; Mourer-Chauviré, 1992), including amphibians and squamates, which were originally briefly listed in Crochet al. (1981). Unfortunately, studies on the herpetofauna from La Bouffie have been sporadic, with few taxa described and figured (Augé, 1987, 2001, 2005; Augé & Brizuela, 2020; Čerňanský & Augé, 2013; Georgalis et al., 2021a; Roček & Lamaud, 1995). These sporadic studies have confirmed the status of La Bouffie as an important locality for the Late Eocene herpetofauna of Western Europe, including some extremely rare taxa in Europe (e.g., Tupinambinae; Augé & Brizuela, 2020) and type specimens of more widespread taxa (*Thaumastosaurus*; Roček & Lamaud, 1995). We here take the opportunity to expand the herpetofauna list by describing several “forgotten” specimens from the study of Roček and Lamaud (1995) plus several previously undescribed specimens from a different collection and present an updated list of the herpetofauna from La Bouffie.

## Geological context

La Bouffie is situated inside the village of Vaylats (Lot, France) within the Parc Naturel Régional du Quercy (PNR). La Bouffie is an ancient phosphate quarry consisting of three main geological features: (1) an excavation well (3 m wide, 15 m deep), (2) a shallow trench showing the start of two collapsed galleries, and (3) a large pile of rubble from the excavations. Specimens have been found in both the pile of rubble (where most of the specimens were collected) and at the bottom of the well (now inaccessible due to a toxic concentration of carbon dioxide gases; T. Pélissié pers. com., November 2024). A diverse mammal fauna has been identified, with two new species erected based on specimens from La Bouffie (Crochet et al., 1981; Godinot & Dagasto, 1983). The associated rodent fauna from La Bouffie suggests a biochronological age of MP 17A (early Priabonian, late Eocene: 37.8–37.5 Ma).

## Materials and methods

Most of these specimens were discovered in the office of the late Professor Jean-Claude Rage at MNHN, by one of us (AL). Most were assigned a collection number with "LB" (La Bouffie) and were part of the material studied in the redescription of *Thaumastosaurus bottii* (Roček & Lamaud, 1995) but never included nor mentioned in the manuscript. The specimens are now stored at the Palaeontological collection of the Museum of Natural History of Toulouse (SW. France). We further include several specimens from La Bouffie that were identified in the collection of the Institute of Sciences of Evolution of the University of Montpellier by one of us (GLG). All specimens from MHNT are curated under the collection numbers MHNT.PAL. 2023.0.31.1–116. All specimens from UM are curated under the collection numbers UM-BFI.

The anatomical nomenclature for salamanders follows Macaluso et al. (2023). Anatomical nomenclature for anurans is based on Lemierre et al. (2021) for cranial and postcranial features and Bolkay (1919) for humeral features. Anatomical nomenclature for squamates follows Čerňanský et al. (2023c).

**Institutional Abbreviations:** MNHN, Muséum national d'Histoire Naturelle, Paris, France; MHNT, Muséum d'Histoire Naturelle de Toulouse, Toulouse, France; NHMW, Naturhistorisches Museum Wien, Vienna; UM, Institute of Sciences of Evolution, University of Montpellier, Montpellier, France.

## Nomenclatural acts

The electronic edition of this article conforms to the requirements of the amended International Code of Zoological Nomenclature (ICZN), hence the new names contained herein are available under that Code from the electronic edition of this article. This published work and the nomenclatural acts it contains have been registered in ZooBank, the official registry of zoological nomenclature for the ICZN. The ZooBank LSIDs (Life Science Identifiers) can be resolved and the associated information viewed through any standard web browser by appending the LSID to the prefix `https://zoobank.org/`. The LSID for this publication is: urn:lsid:zoobank.org:pub:6D91C12E-7780-4F3E-80F6-334D7D76DD68. The LSID for the nomenclatural acts of the new genera and species are presented below in their respective entries.

## Systematic palaeontology

Lissamphibia Haeckel, 1866

Urodela Duméril, 1805

Salamandridae Goldfuss, 1820

Salamandridae indet.

Figure 1
<figure><img src="image_4.png" /><figcaption>**Fig. 1** Salamandridae indet. from La Bouffie. Trunk vertebra (UM-BFI 3197) in anterior (a), posterior (b), dorsal (c), ventral (d), and right lateral (e) views</figcaption></figure>

**Material.** One trunk vertebra (UM-BFI 3197).

**Description.** UM-BFI 3197 is a poorly preserved trunk vertebra (Fig. 1). The centrum is opisthocoelous, with a small anterior condyle (Fig. 1a). The vertebra seems flattened dorso-ventrally (Fig. 1a-e). The neural crest extends alongside the length of the neural arch, increasing posteriorly (Fig. 1c, e). Para- and diapophyses extends posterolaterally, separated by a bony lamina (Fig. 1e). The ventral surface of the centrum is smooth, without any keel nor crest (Fig. 1d).

**Attribution and remarks.** This vertebra is assigned to Salamandridae based on the following characters (Macaluso et al., 2023): (1) lack of ventral keels; (2) opisthocoelous centrum and (3) para- and diapophyses connected by a bony lamina. However, UM-BFI 3197 is too fragmentary and eroded to be more precisely assigned within salamandrids.

Anura Duméril, 1805

Pelodytidae Bonaparte, 1850

Pelodytes Bonaparte, 1850

cf. Pelodytes sp.

Figure 2

**Material.** Two presacral vertebrae (UM-BFI 3166 and UM-BFI 3174).

**Description.** Both vertebrae are small and procoelous (Fig. 2). The centrum is narrow and elongated anteroposteriorly (Fig. 2d, i). Both anterior cotyle and posterior condyle are compressed dorsoventrally (Fig. 2a, b, f, g). The prezygapophyses are elongated anteriorly and oriented dorsomedially (Fig. 2a, c, f, h). The neural arch is

<figure><img src="image_5.png" /><figcaption>**Fig. 2** cf. *Pelodytes* sp. from La Bouffie. a-e, Presacral vertebra (UM-BFI 3166) in anterior (a), posterior (b), dorsal (c), ventral (d), and right lateral (e) views; f-i, presacral vertebra (UM-BFI 3174) in anterior (f), posterior (g), dorsal (h), and ventral (i) views</figcaption></figure>

thin and does not bear a neural spine, and its posterior margin is straight (Fig. 2c, h). The transverse processes are thin, rod-like and oriented posterolaterally (Fig. 2). In ventral view, the lateral walls of the neural canal extend laterally from the centrum (Fig. 2d, i).

**Attribution and remarks.** Both vertebrae are assigned to Pelodytidae based on the following characters (see Rage, 2016): (1) small, narrow procoelous centrum; (2) lateral walls of the neural canal extending laterally from the centrum in ventral view; (3) neural spine absent or weakly projecting posteriorly; and (4) vertebra lightly built. Pelodytidae is composed of a unique extant genus, *Pelodytes* Bonaparte, 1850, and several North American and Asian extinct genera have been referred to this family. In the fossil record of Europe, pelodytid fossil elements are morphologically identical to bones of the modern *Pelodytes* (see Rage, 2016). Thus, we follow Rage (2016) and refer the La Bouffie material to cf. *Pelodytes*.

Neobatrachia Reig, 1958

Ranoides Frost et al., 2006

Natatanura Frost et al., 2006

Pyxicephaloidea Bonaparte, 1850

Pyxicephalidae Bonaparte, 1850

Thaumastosaurus De Stefano, 1903

Thaumastosaurus bottii De Stefano, 1903

Thaumastosaurus cf. bottii

Figure 3a-m
<figure><img src="image_6.png" /><figcaption>**Fig. 3** Elements assigned to *Thaumastosaurus* from La Bouffie. *Thaumastosaurus cf. bottii* (a–m): a–b, incomplete frontoparietal (MHNT.PAL. 2023.0.31.85) in dorsal (a) and ventral (b) views; c–e, incomplete posterior region of a left squamosal (MHNT.PAL. 2023.0.31.64) in lateral (c), medial (d), and dorsal (e) views; f–g, anterior portion of a left squamosal (MHNT.PAL. 2023.0.31.101) in lateral (f) and medial (g) views; h–i, fragmentary ?nasal (MHNT.PAL. 2023.0.31.93) in dorsal (h) and ventral (i) views; j–k, incomplete left maxilla (MHNT.PAL. 2023.0.31.26) in labial (j) and lingual (k) views; l–m, anterior region of a right maxilla (MHNT.PAL. 2023.0.31.1) in labial (l) and lingual (m) views. *Thaumastosaurus* sp. (n–r): n–o, incomplete left angulosplenial (MHNT.PAL. 2023.0.31.89) in dorsal (n) and ventral (o) views; p–r, distal portion of a left humerus (MHNT.PAL. 2023.0.31.90) in ventral (p), dorsal (q), and lateral (r) views. cd, crista dentalis; cmnex, crista mandibulae externae; cpf, crista on processus frontalis; cprd, crista parcornoidae; exs, extremitas spatulate; ifa, incrassation frontoparietalis anterior; lh, lamina horizontalis; obm, orbital margin; or, ornamentation; pcrd, processus coronoideus; pf, processus frontalis; pmx, processus maxillaris; ptp, processus pterygoideus; pzm, processus zygomatico-maxillaris; qja, quadratojugal articular facet; rp, ramus paroticus; scm, sulcus pro cartilagine Meckeli; tsb, tectum supraorbitale</figcaption></figure>

**Material.** Eight incomplete frontoparietals (MHNT.PAL. 2023.0.31.81– MHNT.PAL. 2023.0.31.87 and MHNT.PAL. 2023.0.31.103); 41 incomplete squamosals (MHNT.PAL. 2023.0.31.63– MHNT.PAL. 2023.0.31.71, MHNT.PAL. 2023.0.31.88, MHNT.PAL. 2023.0.31.91, MHNT.PAL. 2023.0.31.92, MHNT.PAL. 2023.0.31.94– MHNT.PAL. 2023.0.31.102, MHNT.PAL. 2023.0.31.104– MHNT.PAL. 2023.0.31.109, MHNT.PAL. 2023.0.31.111, MHNT.PAL. 2023.0.31.112, and MHNT.PAL. 2023.0.31.117); one putative nasal (MHNT.PAL. 2023.0.31.93); 64 fragmentary maxillae (MHNT.PAL. 2023.0.31.1– MHNT.PAL. 2023.0.31.62); and one fragment of an exoccipital (MHNT.PAL. 2023.0.31.72).

## Description and attribution

**Cranial bones:** All specimens are covered in an ornamentation made of deep pits and ridges (honeycombed; Fig. 3a–m). Such ornamentation can be observed in the Eocene *Thaumastosaurus* and *Eopelobates*, both mentioned in the original faunal list of La Bouffie. However, assignment of materials from the Eocene in the Quercy to Pelobatidae needs to be reassessed, as most cranial elements are likely from the pyxicephalid *Thaumastosaurus* (see Rage, 2016). Our cranial elements can be referred to *Thaumastosaurus* based on the following characters: (1) incrassation frontoparietalis separated into a lanceolate anterior impression and two circular posterior impressions (Fig. 3b); (2) anterior portion of the frontoparietals
not diverging medially (Fig. 3a, b); (3) lamella alaris of the squamosals extends anteriorly into a thin process, excluding the maxilla from the orbit (Fig. 3f); (4) squamosals not in contact with the frontoparietals (short ramus paroticus; Fig. 3e); (5) ornamentation extends ventrally on the crista dentalis of the maxillae (Fig. 3j, l); (6) dorsal margin of the maxillae slightly decreasing anteriorly between the processus zygomatico-maxillaris and processus frontalis (Fig. 3j, k); and (7) presence of a nearly vertical crista running on the height of the lingual surface of the processus frontalis (Fig. 3m). A secure assignment to one of the species of *Thaumastosaurus* is difficult as their status and osteological differences are unclear (Georgalis et al., 2023; Lemierre et al., 2021). However, as La Bouffie is the neotype locality of *T. bottii*, we assign our specimens to *Thaumastosaurus cf. bottii*.

*Thaumastosaurus* sp.

Figures 3n–r, 4

**Material.** One left angulosplenial (MHNT. PAL. 2023.0.31.89); one left humerus (MHNT.PAL. 2023.0.31.90); one posterior presacral vertebra (UM-BFI 3163); and one sacral vertebra (UM-BFI 3167).

**Description and attribution**

**Angulosplenial:** MHNT.PAL. 2023.0.31.89 is missing most of its anterior region, and the posteriormost part of the extremities spatulate (Fig. 3n, o). The processus coronoideus is an ovoid flattened plate extending medially (Fig. 3n). The crista paracoronoidae is low and barely marked (Fig. 3n), while the crista mandibulae externa is

well-marked (Fig. 3n). The sulcus pro cartilagine Meckeli is opened dorsolaterally and widens posteriorly (Fig. 3n). This angulosplenial is identical to the one referred to *Thaumastosaurus* (Lemierre et al., 2021: fig. 7b), and thus is assigned to *Thaumastosaurus* sp.

**Humerus:** MHNT.PAL. 2023.0.31.90 is a left humerus missing most of its proximal region and diaphysis (Fig. 3p–r). The preserved portion of the diaphysis is devoid of crista, straight and slender (Fig. 3p). The fossa cubitalis ventralis is shallow and not well-delimited (Fig. 3p). It does not extend proximally but forms a crescent shaped fossa around the proximal margin of the eminentia capitata (Fig. 3p). The latter is as wide as the diaphysis and slightly shifted laterally from the diaphyseal axis (Fig. 3p). The epicondyles are asymmetrically developed (Fig. 3p, q). The epicondylus radialis is barely distinct from the eminentia capitata (Fig. 3p), while the epicondylus ulnaris is moderately developed and extends distally (Fig. 3p). No additional crests are present. This humerus is referred to *Thaumastosaurus* on the following characteristics: (1) slender diaphysis; (2) epicondylus ulnaris moderately developed; and (3) eminentia capitata slightly shifted laterally from the diaphyseal axis (Rage, 2016).

**Presacral vertebra:** UM-BFI 3163 is a rather large presacral vertebra (Fig. 4a–e). Its centrum is well developed and procoelous (Fig. 4a, b). The prezygapophyses are circular, not expanded laterally or anteriorly, and curved dorsomedially (Fig. 4a, c). The neural arch bears an anterior and posterior lamina, connecting the anterior

<figure><img src="image_7.png" /><figcaption>**Fig. 4** *Thaumastosaurus* sp. from La Bouffie, vertebrae. **a–e**, Posterior presacral vertebra (UM-BFI 3163) in anterior (**a**), posterior (**b**), dorsal (**c**), ventral (**d**), and right lateral (**e**) views; sacral vertebra (UM-BI 3167) in ventral view (**f**).</figcaption></figure>
and posterior margins to the neural spine (Fig. 4a, b). The neural spine is broken off (Fig. 4c). It does seem to extend posterodorsally. The transverse processes are broken at their bases but seem oriented almost perpendicular to the vertebral axis (Fig. 4c, d, e). This presacral vertebra is referred to Ranoidea on the following characters (Lemierre et al., 2021; Rage, 2016): (1) procoelous centrum (opisthocoelous centrum in Alytoidea); (2) large size and not lightly built (vs. Pelodytidae) and (3) neural spine extending posterodorsally (vs. extending posteriorly in Pelobatidae). UM-BFI-3163 is identical to posterior presacral vertebrae referred to *Thaumastosaurus* (see Lemierre et al., 2021) and thus is referred to *Thaumastosaurus* sp.

**Sacral vertebra:** UM-BFI 3167 represent a sacral vertebra missing most of its neural arch and dorsal region (Fig. 4f). The centrum bears an anterior condyle and two posterior condyles (Fig. 4f). The prezygapophysis is circular (Fig. 4f). The sacral transverse process is rod-like and projects posterolaterally (Fig. 4f). As for UM-BFI 3163, this vertebra is identical to sacral vertebra referred to *Thaumastosaurus* (Lemierre et al., 2021) and thus is referred to *Thaumastosaurus* sp.

All postcranial elements described here are referred to *Thaumastosaurus* sp. and not *Thaumastosaurus cf. botii* because the postcranial skeleton of this species is not known. *Thaumastosaurus* postcranial elements are only known for *Thaumastosaurus servatus* (Filhol, 1876), and no study has been undertaken to assess potential osteological differences among disarticulated postcrania of the genus.

**Anura indet.**

Figure 5

*Material.* One distal or proximal portion of a tibiofibula (UM-BFI 3164).

*Description and attribution.* UM-BFI 3164 preserves only a portion of a tibiofibula, with a shallow groove delimiting the fused tibia and fibula (Fig. 5). It is too poorly preserved to warrant an assigned within Anura.

Squamata Oppel, 1811

Gekkota Cuvier, 1817

**Gekkota indet.**

Figure 6

*Material.* Eight dentaries (MHNT.PAL. 2023.0.31.118a– MHNT.PAL. 2023.0.31.118g, UM-BFI 3060, UM-BFI 3072, and UM-BFI 3090); one trunk vertebra (UM-BFI 3195); and one sacral vertebra (UM-BFI 3193).

*Description*

**Dentaries:** All dentaries are broken, with almost no teeth preserved (Fig. 6a–f). The largest dentary (MHNT-

PAL.2023.0.31.118b) has around 23 tooth positions preserved (Fig. 6b). When preserved the teeth are small, slender and monocuspid (Fig. 6a). The sulcus Meckeli is fully closed and fused, and the dentaries are “tube-shaped” (Fig. 6a–c).

**Trunk vertebra:** UM-BFI 3195 is small and lightly build (Fig. 6g–k). The centrum is procoelous, with a small cotyle and condyle flattened dorsoventrally (Fig. 6g, h, j). The condyle is not inclined in lateral view (Fig. 6k). The prezygapophyses are small and strongly oriented dorso-medially (Fig. 6a, i). The neural crest is broken but does not seem to extend past the postzygapophyses (Fig. 6i, k). The subcentral margins are barely visible, and a pair of subcentral foramina are present on the ventral surface of the centrum (Fig. 6j).

**Sacral vertebra:** UM-BFI 3193 is small and lightly build (Fig. 6l–p). The centrum is amphicoelous, with the notochordal canal opened (Fig. 6l, m). The vertebra is very damaged, but the ventral view shows the fusion between two vertebrae (Fig. 6o). The pleurapophyses are poorly preserved, but their orientation shows their meet distally (Fig. 6o, p).

*Attribution and remarks.* The dentition and closure of the sulcus Meckeli are diagnostic for dentaries of Gekkota in Europe (Augé, 2005; Čerňanský et al., 2023a; Daza et al., 2014). In the Quercy Phosphorites two genera have been recognized, i.e., *Bauersaurus Čerňanský* et al., 2023a, known exclusively from the early Eocene (MP 10–11) locality of Cos, and the younger, relatively more widespread, *Cadurcogekko* (Augé, 2005; Čerňanský

<figure><img src="image_8.png" /><figcaption>**Fig. 5** Anura indet. from La Bouffie. Distal or proximal portion of a tibiofibula (UM-BFI 3164) in transversal view</figcaption></figure>
<figure><img src="image_9.png" /><figcaption>**Fig. 6** Gekkota indet. from La Bouffie. **a**, Left dentary (MHNT.PAL. 2023.0.31.118a) in lingual view; **b–c**, left dentary (MHNT.PAL.2023.0.31.118b) in lingual (**b**) and labial (**c**) views; **d–f**, left dentary (UM-BFI-3072) in lingual (**d**), dorsal (**e**), and labial (**f**) views; **g–k**, trunk vertebra of Gekkota indet. "morphotype 1" (UM-BFI 3195) in anterior (**g**), posterior (**h**), dorsal (**i**), ventral (**j**), and left lateral (**k**) views; **l–p**, sacral vertebra of Gekkota indet. "morphotype 2" in anterior (**l**), posterior (**m**), right lateral (**n**), ventral (**o**), and dorsal (**p**) views</figcaption></figure>

et al., 2023a; Daza et al., 2014; Georgalis et al., 2021a). Unfortunately, no differences between the two genera are known on their dentaries (the diagnosis of *Bauersaurus* is based on the maxilla; see Čerňanský et al., 2023a). Besides, outside Quercy, five other genera of gekkotans have also been established from the Eocene of Europe: *Dollogekko Čerňanský et al., 2022*, from the early Eocene

of Belgium (Čerňanský et al., 2022), *Laonogekko* Augé, 2003, from the early Eocene of the Paris Basin in France (Augé, 2003), the amber-embedded *Yantarogekko* Bauer, Böhme & Weitschat, 2005, from the early Eocene of the Baltic Sea region (Bauer et al., 2005), *Geiseleptes* Villa et al., 2022, from the early to early middle Eocene of Germany (Villa et al., 2022), and *Rhodanogekko* Hoffstetter,
1946, from the middle Eocene of France (Hoffstetter, 1946). Thus, we tentatively assign all our specimens to Gekkota indet.

UM-BFI 3193 is assigned to Gekkota on the basis of an amphicoelous condition (known, among squamates, only in Gekkota in the Cenozoic of Europe; Augé, 2005; Čerňanský et al., 2018; Daza et al., 2014; Delfino et al., 2011; Estes, 1983). Amphicoelous vertebrae have in the past been assigned to *Cadurcogekko* (Augé, 2005; Rage, 1988) but this assignment is not fully confirmed, because no articulated specimens of this genus are known.

UM-BFI 3195 is more puzzling. It does match the general morphology of known Cenozoic gekkotans from Europe (Daza et al., 2014) but differs in being procoelous.

Procoelous vertebrae are known in certain extant gekkotan taxa (Hoffstetter & Gasc, 1969) but have never been documented in the Cenozoic fossil record in Europe (Daza et al., 2014). The presence of both amphicoelous and procoelous vertebral material assigned to Gekkota indicates that at least two species of gekkotans were present in La Bouffie. It also marks the first occurrence of a procoelous gekkotan in the Cenozoic fossil record of Europe.

Lacertoidea Oppel, 1811 (sensu Pyron et al., 2013)

Lacertidae Oppel, 1811

Lacertidae indet.

Figures 7, 8

<figure><img src="image_10.png" /><figcaption>**Fig. 7** Lacertidae indet. "morphotype 1" from La Bouffie. Right dentary (UM-BFI 3061) in lingual (a), ventrolingual (b), dorsal (c), and labial (d) views</figcaption></figure>
<figure><img src="image_11.png" /><figcaption>**Fig. 8** Lacertidae indet. "morphotype 2" from La Bouffie. Right dentary (UM-BFI 3066) in lingual (a), dorsolingual (b), and labial (c) views</figcaption></figure>

**Material.** Two right dentaries (UM-BFI 3061 and UM-BFI 3066).

**Description.** UM-BFI 3061 is a small dentary missing only a few teeth and small part of the posterior region (Fig. 7a-c). The dentary is elongated anteroposteriorly, and its ventral margin is slightly arched (Fig. 7a). 19 teeth are preserved, with three teeth emplacements, bringing thus the total number to 22 (Fig. 7b). The dentition is pleu-rodont and heterodont (Fig. 7a, b). The first four anterior teeth are inclined anteriorly, unicuspid and slightly can-iniform (Fig. 7a). Starting at the sixth posterior, the teeth

become distinctly bicuspid, with a small anterior cusp and a large, pointed posterior one (Fig. 7a-c). The poste-riormost teeth also seem to exhibit a tricuspid condition, with a very faint posterior cusp (Fig. 7a). All teeth possess a high non-striated crown, with half of their height being above the parapet (Fig. 7a, b). The subdental shelf bears a deep sulcus dentalis (Fig. 7b). The subdental shelf is thin posteriorly and widens dorsoventrally up to the level of the symphysis (Fig. 7a). The shelf is more curved than the ventral margin of the dentary (Fig. 7a). The sulcus Meckeli is wide and is opened ventrolingually posteriorly (Fig. 7a).
The sulcus narrows gradually anteriorly and opens ventrally at the level of the symphysis (Fig. 7a). The intramandibular septum is visible and the alveolar foramen opens at the level of the 18th tooth (counting from anterior; Fig. 7a). The facet for the articulation with the splenial is present on the ventral surface of the subdental shelf anteriorly to the eighth tooth position (Fig. 7a). A well-developed facet for the anteromedial process of the coronoid is present on the posterior region of the subdental shelf, just posterior of the tooth row (Fig. 7a). On its lingual surface, the facet for the anterolateral process of the coronoid is shallow and does not extend past the last teeth (Fig. 7a, b). A row of six labial foramina pierces the labial surface (Fig. 7d).

UM-BFI 3066 represents a small dentary missing its posterior region (Fig. 8a-c). The dentary is elongated anteroposteriorly, and the ventral margin is straight (Fig. 8a). UM-BFI 3066 preserves 18 teeth positions and 13 teeth (most are broken; Fig. 8). The implantation is pleurodont, and the teeth are high crowned, with half of their height projecting above the parapet (Fig. 8b, c). The teeth are slender (Fig. 8a). Although broken, it is evident that the anterior teeth are projected anteriorly, while the median ones are perpendicular to the long axis of the bone (Fig. 8a). The posterior teeth have their crown curved posteriorly (Fig. 8a). The latter is bicuspid, with a large posterior cusp and a faint anterior one (Fig. 8a). The teeth do not bear any striations (Fig. 8), but we cannot exclude that this lack of striation is not simply due to some degree of corrosion (see Smith et al., 2021). The subdental shelf is moderately developed, with a rounded lingual margin (Fig. 8a) and bears a strong sulcus dentalis (Fig. 8b). The sulcus Meckeli opens ventrolingually (Fig. 8a). It is wide posteriorly, but narrows gradually anteriorly, until it is solely opened ventrally (Fig. 8a). Five labial foramina are present on the labial surface of the dentary (Fig. 8c).

**Attribution.** UM-BFI 3061 can be referred to Laceridae on the basis of possessing: (1) bicuspid / tricuspid dentition; (2) a deep sulcus dentalis; (3) an arched ventral margin; and (4) the lateral overlap of the postero-dorsal margin of the dentary by the coronoid (see e.g., Estes et al., 1988; Augé, 2005; Čerňanský et al., 2016b; Čerňanský & Syromyatnikova, 2019; Villa & Delfino, 2019; Čerňanský, 2025). Among European Eocene lacertids, two small species are known to exhibit bicuspid teeth, *Dormaalisaurus girardoti* Augé & Smith, 2002, and *Gracilicerta sindexi* Augé, 2005. Affinities of UM-BFI 3061 with *Dormaalisaurus* Augé & Smith, 2002, can be excluded, as the La Bouffie specimen: (1) lacks striations on the teeth crowns; (2) has the base of its teeth slightly expanded (no expansion is observed in *Dormaalisaurus*); and (3) a more arched dentary (see Augé & Smith, 2002).

It does, however, resemble *Gracilicerta sindexi* on those same characters. However, our specimen from La Bouffie differs from the holotype (UM-SND 623) of *G. sindexi* from La Sindou (MP 18-19), also in Quercy, in: (1) having bicuspid teeth with a more developed anterior second cusp; (2) posterior teeth exhibiting a tricuspid condition; (3) teeth above the dentary parapet by half their length (only one third in *G. sindexi*); (4) a subdental shelf moderately expanded dorsoventrally on its anterior portion (subdental shelf deep and very expanded dorsoventrally on its anterior portion in *G. sindexi*); (5) tooth row composed of 22 teeth (24-26 in *G. sindexi*); (6) a shallow facet for the anterolateral process of the coronoid that does not extend past the level of the last tooth (deep and extending up to the level of the third posterior tooth in *G. sindexi*; see Augé, 2005: figs. 83, 84); (7) the Meckelian groove is open medially, as in other lacertids (in *G. sindexi*, it opens ventrally in the anterior region, like in anguimorphs and unlike lacertids); and (8) the homogenous curvature of the ventral margin of the dentary. Thus, UM-BFI 3071 represents an indeterminate lacertid from La Bouffie, informally referred herein as "Lacertidae indet. 1".

UM-BFI 3066 is also referred to Lacertidae (see e.g., Augé, 2005; Čerňanský & Syromyatnikova, 2019; Villa & Delfino, 2019; Čerňanský, 2025) based on the following combination of characters: (1) bicuspid dentition, with a distally displaced main cusp; and (2) a prominent sulcus dentalis. UM-BFI 3066 differs from UM-BFI 3061 in (1) having posterior bicuspid teeth (tricuspid in UM-BFI 3061) and (2) having the sulcus Meckeli opening anteriorly only ventrally (ventromedially opened in UM-BFI 3061). Thus, UM-BFI 3066 likely represents a second indeterminate lacertid from La Bouffie, informally referred herein as "Lacertidae indet. 2".

**Amphisbaenia Gray, 1844**
**Amphisbaenia indet.**

Figure 9

**Material.** Two incomplete trunk vertebra (UM-BFI 3095 and UM-BFI 3147).

**Description.** Both vertebrae are small and squared (i.e., approximately as wide as it is long; Fig. 5c, s). The centrum is procoelous and depressed (Fig. 9a-d). The ventral surface of the centrum is smooth, with parallel subcentral margins, and two large subcentral foramina opening at the anterior half of the centrum (Fig. 9d). The neural arch is flattened dorsally, with a small neural ridge extending across its entire length (Fig. 9c). On the posterior region of the neural arch, a triangular tuberosity is preserved (Fig. 9c).

**Attribution and remarks.** UM-BFI 3095 and UM-BFI 3147 are assigned to the Amphisbaenia based on the following characters (Augé, 2012; Estes, 1983; Georgalis
<figure><img src="image_12.png" /><figcaption>**Fig. 9** Amphisbaenia indet. from La Bouffie. **a–e**, trunk vertebra (UM-BFI 3095) in anterior (**a**), posterior (**b**), dorsal (**c**), ventral (**d**), and left lateral (**e**) views; **f–j**, trunk vertebra (UM-BFI 3147) in anterior (**f**), posterior (**g**), dorsal (**h**), ventral (**i**), and right lateral (**j**) views</figcaption></figure>

et al., 2018): (1) depressed neural arch; (2) smooth ventral surface of the centrum; (3) neural spine reduced to a triangular tuberosity; and (4) hemispherical synapophyses. Usually, trunk vertebrae of amphisbaenians cannot be used for a more precise allocation within the clade, with a few only exceptions such as rhineurids (Augé, 2012; Čerňanský, 2023; Georgalis et al., 2018, 2024a, 2024b). Therefore, these two vertebrae from La Bouffie are here only identified as Amphisbaenia indet.

Toxicofera Vidal & Hedges, 2005

Iguania Cuvier, 1817

Pleurodonta Cope, 1864 (sensu Frost et al., 2001)

Corytophanidae Fitzinger, 1843

Geiseltaliellus Kuhn, 1944

Geiseltaliellus lamandini (Filhol, 1877)

Geiseltaliellus cf. lamandini

Figure 10

**Material.** One incomplete right dentary (UM-BFI 3079).

**Description.** UM-BFI 3079 is a fragment of a large dentary (Fig. 10a). Eight teeth emplacements (including six teeth) are preserved (Fig. 10a). The teeth are high-crowned, with one-third of their height projecting above the parapet (Fig. 10b). The teeth are straight and slender, expect for the posteriormost one, the latter

being wider (Fig. 10a). One tooth is complete and shows a tricuspid condition, with a large central cusp and two small lateral ones (Fig. 10a, b). The subdental shelf is moderately developed, with a rounded lingual margin and lacks a sulcus dentalis (Fig. 10a). The ventral wall bears an inframeckelian lip parallel to the subdental shelf (Fig. 10a). As such, the sulcus Meckeli narrowly opens lingually (Fig. 10a). On the labial surface, two mental foramina are preserved (Fig. 10b).

**Attribution and remarks.** UM-BFI 3079 is reminiscent of *Geiseltaliellus lamandini* based on the following combination of characters (see Augé, 2005): (1) absence of a sulcus dentalis; (2) a sulcus Meckeli narrowing anteriorly; (3) slender and straight tricuspid teeth; (4) presence of inframeckelian lip parallel to the subdental shelf; and (5) enlarged posterior teeth. It is worth noting though that the first four characters of this combination are also present in other pleurodontans, including the early Eocene North American genus *Suzanniwana* Smith, 2009a, which has anyway been suggested to bear much resemblance to *Geiseltaliellus*, though being more primitive (Smith, 2009a). In any case, due to the incompleteness of the only specimen from La Bouffie, we treat this species level identification as tentative. Furthermore, it should be noted that the referral of *G. lamandini* (originally established as a new species of *Lacerta* Linnaeus,
<figure><img src="image_13.png" /><figcaption>**Fig. 10** *Geiseltaliellus cf. lamandini* from La Bouffie. Right dentary (UM-BFI 3079) in lingual (a) and labial (b) views</figcaption></figure>
1758, by Filhol [1877]; subsequently recombined into the genus *Pseudolacerta* by Hoffstetter [1942]; and subsequently recombined into the genus *Geiseltaliellus* by Augé [2005]) to *Geiseltaliellus* is uncertain, as its lacks the known autapomorphies of the genus (Smith, 2009b).

**Pleurodonta incertae sedis**

*Cadurciguana Augé, 1987*

*Cadurciguana hoffstetteri Augé, 1987*

Figure 11

*Material.* Two incomplete left dentaries (MHNT.PAL. 2023.0.31.119a and MHNT.PAL. 2023.0.31.119b).

**Description.** The dentary preserves 13 tooth positions, with four teeth (Fig. 11a, b). The dentition is pleurodont and heterodont (Fig. 11a, b). Teeth are straight and slender (Fig. 11a, b). The anteriormost tooth has a pointed apex, while the other three are tricuspid with their lateral cusps small (Fig. 11a). In labial view, a third of the teeth are visible above the parapet (Fig. 11c, d). The labial surface is pierced by two foramina (Fig. 11c, d). In lingual

view, the sulcus Meckeli is fully closed by the expansion of the ventral wall (Fig. 11a, b). A thin groove / suture is visible medially between the subdental shelf and the ventral wall of the dentary (Fig. 11a, b).

**Attribution and remarks.** These small dentaries are referred to *Cadurciguana hoffstetteri* (the type and only known species of the genus *Cadurciguana*, originally typified from the MP 19 locality of Escamps C, Quercy; Augé, 1987, 2005) based on the following characters (see Augé, 2005): (1) heterodont dentition with anterior teeth monocuspid and posterior teeth tricuspid with small lateral cusps; (2) a sulcus Meckeli fully closed and fused ventromedially by the expansion of the ventral wall; and (3) presence of a small groove extending anteriorly from the posterior end of the closed and fused sulcus Meckeli. Nevertheless, it has to be emphasized that the particularly the former two characters are not really diagnostic, as they represent widespread features, shared also with numerous (perhaps even hundreds of) extant pleurodontan taxa. However, still, as far as it regards the European fossil record, this combination of characters appears to be unique to *Cadurciguana*.

**Pseudolacerta De Stefano, 1903**

aff. *Pseudolacerta* sp.

Figure 12

*Material.* One right maxilla (UM-BFI 3081); and one dentary (UM-BFI 3100).

**Description**

**Maxilla:** UM-BFI 3081 preserves the posterior region of the right maxilla (Fig. 12a–d). Four broad pleurodont teeth are preserved (Fig. 12a, b). They are tricuspid, with a large median cusp and two faint mesial and distal accessory cusps (Fig. 12a, b).

**Dentary:** UM-BFI 3100 is a fragment of a large dentary (Fig. 12e–f). Three caniniform teeth are preserved (Fig. 12e, f). They are broad and slightly curved posteriorly (Fig. 12e).

**Attribution and remarks.** Both maxilla and dentary resemble elements assigned to *Pseudolacerta* on the following characters (Augé, 2005):

(1) anterior teeth large and caniniform

(2) teeth with broad base (vs. slender in other pleurodontans, like *Cadurciguana*)

(3) its large size (compared to other pleurodontans)

However, both UM-BFI 3081 and UM-BFI 3100 are too poorly preserved to warrant a definite assignment to *Pseudolacerta*. Thus, we assign both specimens to aff. *Pseudolacerta* sp., in order to highlight the strong similarities between the La Bouffie specimens and that genus.

<figure><img src="image_14.png" /><figcaption>**Fig. 11** *Cadurciguana hoffstetteri* from La Bouffie. Left dentary (MHNT.PAL. 2023.0.31.119a). Photographs of the specimen in lingual (a) and labial (c) views; interpretative drawings of the specimen in lingual (b) and labial (d) views. Abbreviations: sds, subdental shelf; sM, sulcus Meckeli</figcaption></figure>
<figure><img src="image_15.png" /><figcaption>**Fig. 12** aff. *Pseudolacerta* sp. from La Bouffie. **a–d**, Right maxilla (UM-BFI 3081) in labial (**a**), lingual (**b**), dorsal (**c**), and posterior (**d**) views; **e–f**, anterior portion of a dentary (UM-BFI 3100) in labial (**e**) and lingual (**f**) views</figcaption></figure>

**?Pleurodonta incertae sedis**

*Phosphoriguana* gen. nov.

ZooBank registration.

urn:lsid:zoobank.
org:act:30E2FB55-7E96-4256-BD03-8626D1C0503C.

**Type species.** *Phosphoriguana peritechne* gen. et sp. nov.

**Etymology.** The new genus name *Phosphoriguana* originates from the Greek word “φώσφορος” (“phosphoros”), referring to the Phosphorites du Quercy, and the extant genus *Iguana*.

**Diagnosis.** As for the type and only known species, *Phosphoriguana peritechne* gen. et sp. nov.

*Phosphoriguana peritechne* gen. et sp. nov.

Figure 13

ZooBank registration.

urn:lsid:zoobank.
org:act:8C92DEA5-EE9E-427F-9929-D21F88366D87.

**Etymology.** The species epithet originates from the Greek word “peritechne” (“περίτεχνη”), meaning “elaborate”, “crafted with beautiful art”, referring to the beautiful, elaborate shape of the teeth of the new taxon.

**Holotype.** One complete left dentary (UM-BFI 3057).

**Differential Diagnosis.** *Phosphoriguana peritechne* gen. et sp. nov. differs from *Cadurciguana* in: (1) having an opened sulcus Meckeli (closed and fused in *C. hoffstetteri*) (see Augé, 2005); (2) having more developed accessory cusps; and (3) having a more arched ventrally margin of the dentary. *Phosphoriguana peritechne* gen. et sp. nov.

differs from *Geiseltaliellus* in lacking the presence of an inframeckelian lip narrowing or closing the sulcus Meckeli (see Augé, 2005; Smith, 2009b). *Phosphoriguana peritechne* gen. et sp. nov. differs from *Geiseltaliellus lamandini* in having an arched ventral margin of the dentary (see Augé, 2005). *Phosphoriguana peritechne* gen. et sp. nov. differs from *Bifurcodentodon Čerňanský* et al., 2023b in lacking the dentition made of two main cusps, with several accessory cusps (see Čerňanský et al., 2023b). *Phosphoriguana peritechne* gen. et sp. nov. differs from *Pseudolacerta* De Stefano, 1903, in lacking the strongly heterodont dentition and lacking the enlarged anterior caniniform teeth present in the latter genus (see Augé, 2005).

**Type locality and age.** La Bouffie, fissure fill located in the village of Vaylats (Lot, SW France); late Eocene (MP 17A); the species is so far known exclusively from the type locality.

**Description of the holotype.** UM-BFI 3057 is a complete dentary missing only a few teeth (Fig. 13). The dentary is elongated anteroposteriorly and large (Fig. 13a, b). 15 teeth are preserved, and at least six additional tooth positions can be identified, but the presence of sediment obscures most of the region, preventing a definitive total count (Fig. 13c). A broken tooth shows the implantation to be pleurodent; the dentition is heterodont (Fig. 13a, c). The first three anterior teeth are monocuspid, with a posteriorly oriented triangular apex (Fig. 13a, b). Posteriorly, the teeth become tricuspid, with a large central cusp and two smaller mesial
<figure><img src="image_16.png" /><figcaption>**Fig. 13** *Phosphoriguana peritechne* gen. et sp. nov. from La Bouffie. Holotype left dentary (UM-BFI 3057) in lingual (a), labial (b), and dorsal (c) views; (d), close-up of the tricuspid teeth in lingual view.</figcaption></figure>
and distal accessory cusps of equal size well separated from the central one (Fig. 13d). The posterior teeth are also larger and longer than the anterior ones (Fig. 13a). No sulcus dentalis seems to be present (Fig. 13c). The subdental shelf is concave ventrally and expands only slightly anteriorly (Fig. 13b). On the ventral surface of the subdental shelf, a well-developed facet for the splenial extends anteriorly up to the sixth tooth position (starting from the anteriormost; Fig. 13a). The ventral side of the sulcus Meckeli also bears a facet for the splenial, extending from the second posteriormost tooth up to the third tooth position anteriorly. The sulcus Meckeli is widely opened ventrolingually posteriorly, and progressively narrows anteriorly (Fig. 13a). At the level of the anteriormost five teeth, the subdental shelf covers lingually the sulcus Meckeli up to the symphysis (Fig. 13a). On the labial surface, a row of eight labial foramina opens mid-length of the surface (Fig. 13b). Both angular and coronoid processes are symmetrically developed (Fig. 13b). Moreover, there is a distinct groove on the posterolabial surface of the dentary for an anterolateral process of the coronoid. This groove seems to be more complex than usual (for pleurodontan standards), with an anteroposterior ridge running from front to back. It does not broaden anteriorly but might be dorsoventrally short (Fig. 13a).

**Attribution and remarks.** Two synapomorphies have been proposed on the dentary for Pleurodonta (Gauthier et al., 2012): (1) the restriction of the sulcus Meckeli; and (2) the anteromedial process of the coronoid wrapping under the level of the teeth row. UM-BFI 3057 only possesses the second character and thus is tentatively referred to Pleurodonta.

Among known European pleurodontans, *Phosphoriguana* gen. nov. can be differentiated from all known genera (see *Differential Diagnosis* above). Outside Europe, a large number of pleurodontans is known from the Eocene of North America, pertaining to a number of extinct genera (e.g., Estes, 1983; Gilmore, 1928; Scarpetta, 2020; Smith & Gauthier, 2013; Smith, 2006, 2009a, 2011a, 2011b). The shape and dentition of the holotype dentary UM-BFI 3057 does not also match with the corresponding morphology of the North American taxa. Thus, we establish a new genus and species in order to accommodate the dentary UM-BFI 3057.

Even though its distinctive anatomical features, the new taxon *Phosphoriguana peritechne* gen. et sp. nov. cannot be confidently referred to Pleurodonta based solely on the above-described features. As a matter of fact, pleurodont tooth implantation, tricuspid dentition, and lack of a sulcus dentalis are indeed typical features of pleurodontans, however, these can be also observed also in some members of Teiidae (e.g., genus *Kentropyx* Spix, 1825) and Lacertidae (e.g., Arnold et al., 2007). Furthermore,

our current knowledge about potential synapomorphies in the jaws of Pleurodonta is still limited, and as a matter of fact, only a few have now been pointed out. Two were proposed by Smith (2009b): (1) in the maxilla, a separate foramen for the subnarial artery on the premaxillary process; and possibly (2) in the dentary, a wrapping of the anteromedial process of the coronoid underneath the tooth row. (that latter was suggested by Smith, 2009b but was recovered as a synapomorphy by Gauthier et al., 2012) Additionally, Gauthier et al. (2012) identified a third synapomorphy: (3) a restriction (but not closure, much less fusion) of the Meckelian groove as a synapomorphy of Pleurodonta and part of its stem. For further discussion of these characters, see Smith (2020a, 2020b, 2020c) definitions of Pan-Iguania, Pan-Acrodonta and Pan-Iguanidae. The holotype dentary (UM-BFI 3057) of *Phosphoriguana peritechne* gen. et sp. nov. from La Bouffie seems to possess character (2) but not (3), so the evidence for its taxonomic attribution to Pleurodonta is somehow ambiguous. To the contrary, character (3) in UM-BFI 3057 really deviates from the typical pleurodontan pattern: practically, pleurodontans - with the exception of Hoplocercidae - conform to character (3) and do not normally show such a widely open Meckelian groove, as observed in the new taxon from La Bouffie. Outside Pleurodonta, an alternative, potential taxonomic allocation of *Phosphoriguana peritechne* gen. et sp. would be that this holotype dentary (UM-BFI 3057) pertains to the same taxon as the frontal from La Bouffie that was originally described as a tupinambine teiid by Augé and Brizuela (2020: fig. 2; specimens MNHN.F.BFI1877). All these being said, *Phosphoriguana peritechne* gen. et sp. is only tentatively referred to Pleurodonta and we anticipate that future (ideally articulated) specimens may shed some more light on its precise taxonomic affinities within other lizards.

Anguimorpha Fürbringer, 1900

Glyptosauridae Marsh, 1872 (sensu Čerňanský et al., 2023c)

Glyptosaurinae Marsh, 1872 (sensu Čerňanský et al., 2023c)

Cadurcopanoplos gen. nov.

ZooBank registration. urn:lsid:zoobank.org:act:C41A3086-E91C-44D4-87EA-ABEF5CB38255.

Type species. Cadurcopanoplos vaylatsensis gen. et sp. nov.

**Etymology.** The first part of the new genus name *Cadurcopanoplos* originates from Cadurcum (or Divona Cadurcorum), the Latin name of the town of Cahors, that is situated near the type locality, alluding also to the tribe of Cadurci, who lived during Roman times in the area of the Phosphorites du Quercy. The second part of the
<figure><img src="image_17.png" /><figcaption>**Fig. 14** *Cadurcopanoplos vaylatsensis* gen. et sp. nov. from La Bouffie. Holotype frontal (MHNT.PAL. 2023.0.31.114). Photographs of the specimen in dorsal (**a**), ventral (**c**) and left lateral (**e**) views; interpretative drawings of the specimen in dorsal (**b**), ventral (**d**), and left lateral (**f**) views. **alp**, anterolateral process; **amp**, anteromedial process; **fcc**, frontal cranial crest; **fn**, facet for nasal articulation; **ppl**, processus posterolateralis; **pof**, postfrontal articulation facet; **prf**, prefrontal articulation facet. Grey represents damaged area</figcaption></figure>

new name originates from the Greek word “panoplos” (“πάνοπλος”), meaning “in full armor”, alluding to the extensive armor that covered the body of glyptosaurids.

**Diagnosis.** As for *Cadurcopanoplos vaylatsensis* sp. nov., the type and only known species.

*Cadurcopanoplos vaylatsensis* gen. et sp. nov.
Figures 14, 15
<figure><img src="image_18.png" /><figcaption>**Fig. 15** *Cadurcopanoplos vaylatsensis* gen. et sp. nov. from La Bouffie, tentatively referred specimen. Right dentary (UM-BFI 3070) in lingual (a), labial (b), dorsal (c), anterior (d), and posterior (e) views; (f), close-up of the posterior teeth in lingual view</figcaption></figure>

**ZooBank registration.** urn:lsid:zoobank.org:act:B1B4A2D2-A7B4-46AF-8188-A3D3A9367792.

**Etymology.** The species epithet *vaylatsensis* originates from the village of Vaylats (Department of Lot; Region of Occitanie), where the fossil locality of La Bouffie is situated.

**Holotype.** Incomplete fused frontal preserving the anterior and medial portion of the bones (MHNT.PAL. 2023.0.31.114).

**Additional referred material.** Tentatively referred to the same species is also one partial right mandible (UM-BFI 3070).

**Differential Diagnosis.** A member of Glyptosaurinae differing from all other Glyptosauridae in having a unique pattern of polygonal cephalic osteoderms covering the frontal where the first anterior central osteoderms are fused into a single diamond shaped elements reaching more anteriorly (half its length) than the larger and wider first lateral osteoderms, the latter in contact medially, separating the first and second central osteoderms by a short anteroposterior sulcus. This pattern differentiates the new genus and species from *Sullivanosaurus Čerňanský, Tabuce & Vidalenc, 2023d*, where the first anterior central osteoderms that are fused to the underlying frontal, are slightly anterior to the larger first lateral osteoderms, the latter are not in contact medially. This pattern further differentiates the new genus and species

from *Gaultia* Smith, 2009a, which is characterized by wide chevron-shaped lateral osteoderms. The new genus and species can be further differentiated from all other glyptosaurines by the following combination of characters: (1) anterior osteoderms are apically flat as *Sullivanosaurus* and *Gaultia*, not thick (*Placosaurus* Gervais, 1848) and not bulbous (*Stenoplacosaurus* Sullivan & Dong, 2018, *Glyptosaurus* Marsh, 1871, *Eoglyptosaurus* Sullivan, 1979b, and *Helodermoides* Douglass, 1903); (2) fewer rows of osteoderms between orbits than in *Placosaurus*, *Stenoplacosaurus*, *Glyptosaurus*, *Eoglyptosaurus*, and *Helodermoides*; (3) Second lateral osteoderms not in contact medially (contra *Sullivanosaurus*); (4) concave lateral margin of the frontal (unlike in *Helodermoides*); (5) fused frontals (unlike in *Stenoplacosaurus*); and (6) anterior portion of the frontals narrow (vs. wider in *Gaultia*, *Glyptosaurus*, *Placosaurus*, and *Sullivanosaurus*). For more details and thorough comparisons with other taxa, see the section "Attribution and remarks of the holotype" below.

**Type locality and age.** La Bouffie, fissure fill located in the village of Vaylats (Lot, SW France); late Eocene (MP 17A); the species is so far known exclusively from the type locality.

**Description of the holotype.** The holotype (MHNT.PAL. 2023.0.31.114) is an incomplete frontal, preserving its anterior region and most of its median one (Fig. 14).
Both frontals are fully fused, with a faint trace of a medial suture anteriorly (Fig. 14c, d). The lateral margin is con-cave, and the bone widens posteriorly (Fig. 14a, b). The dorsal surface is covered by osteoderms of mostly polyg-onal outline (Fig. 14a, b). They are all fused to the under-lying bone separated from one another by sulci (Fig. 14a, b). The anterior osteoderms are apically flat (Fig. 14a); posteriorly, these seem to become a bit “bumpier”. The ornamentation is made of small, rounded tubercles arranged in a radiated pattern on each (Fig. 14a, b). The anterior portion of the frontal is smooth and devoid of any osteoderms (Fig. 14a, b), suggesting the anteriormost osteoderms might be missing. A broad anteromedial (nasal) process is present, although broken (Fig. 14a, b). It is flanked by two notches for the articulation with the nasals (Fig. 14a, b). The base of the anterolateral (prefron-tal) processes are also preserved (Fig. 14a, b). They might be shorter than the anteromedial process.

On the dorsal surface, posterior to the smooth ante-rior region, three osteoderms are present (represent-ing the first preserved row; Fig. 14a, b). There is no trace of sutures on the central osteoderm. The latter is nar-row, anteroposteriorly elongated and diamond-shaped (Fig. 14a, b). It extends more anteriorly than the first lat-eral osteoderms by more than half its length (Fig. 14a, b). The first lateral osteoderms are far larger than (twice the width of) than the central one (Fig. 14a, b). Their lateral margin is rounded, while their medial margin is “U-shaped” (Fig. 14a, b). Both first lateral osteoderms are in contact medially, separating the first and second central s by a short anteroposterior sulcus (Fig. 14a, b). The sec-ond central osteoderm is smaller than the first and hexag-onal (Fig. 14a, b). The second lateral osteoderms are also large (Fig. 14a). The lateral margin is almost straight (fol-lowing the lateral margin of the underlying bone; Fig. 14a) and they are not in contact medially. Posterior to the sec-ond central osteoderm, a pair of osteoderms are wedged between the two second lateral osteoderms (Fig. 14a). Due to their poor preservation, it is difficult to assess if they are from a central or lateral row, although the one on the right does not pertain to the lateral row. Posterolat-eral to the second right lateral osteoderm, a small patch of bone, devoid of any ornamentation, is interpreted as the base of the posterolateral process (Fig. 14a).

In ventral view, the cranial crests are robust and well developed (Fig. 14c). They narrow at mid-length, before diverging posteriorly (Fig. 14c). They meet anteriorly to form a rounded anterior margin (Fig. 14c). An anter-oposteriorly elongated articular facet for the prefrontal is visible on each side of the frontal anteriorly (Fig. 14c, e). Another incomplete facet, smaller, for the articulation for the postfrontal, is preserved posteriorly (Fig. 14c, e). The prefrontal and postfrontal facets are separated along the

orbital margin (meaning that the frontal also contributed to it).

**Attribution and remarks of the holotype.** MHNT. PAL. 2023.0.31.114 can be assigned to the Glyptosauri-dae based on the presence of osteoderms with an orna-mentation made of small tubercles (Čerňanský et al., 2023c; Sullivan, 2019; Sullivan & Augé, 2006). Further-more, MHNT.PAL. 2023.0.31.114 can be referred to Glyptosaurinae (sensu Čerňanský et al., 2023c; Glyp-tosaurini of Sullivan, 1979b) based on the fragmenta-tion of the osteodermal crust into numerous, smaller, polygonal osteoderms (e.g., Čerňanský et al., 2023c; Estes, 1983; Gauthier, 1982; Smith, 2009a). MHNT.PAL. 2023.0.31.114 can thus be readily differentiated from the North American *Melanosaurus* Gilmore, 1928, on this character. The “melanosaurine” *Paraplacosauriops* Augé & Sullivan, 2006, from the Eocene of France, is consid-ered to differ from MHNT.PAL. 2023.0.31.114 in this fea-ture (in *Paraplacosauriops*, the frontal is unknown, but we consider that its placement as a “melanosaurine” indi-cates its frontal followed the configuration of *Melano-saurus*). It can also be excluded from the Helodermatidae (occasionally also present in the late Eocene of Europe; Augé, 2005; Georgalis et al., 2021a; Hoffstetter, 1957) in lacking hexagonal bulbous osteoderms (Mead et al., 2012). It can also be differentiated from the helodermatid *Eurheloderma gallicum* Hoffstetter, 1957, otherwise pre-viously also described from La Bouffie on the basis of ver-tebrae (Augé, 2005), in having an ornamentation made of small tubercles (granulate aspect in *Eurheloderma* Hoff-stetter, 1957; e.g., see Augé, 2005: fig. 181). Thus, MHNT. PAL. 2023.0.31.114 is assigned to the Glyptosaurinae.

Glyptosaurinae (sensu Čerňanský et al., 2023c) com-prises several genera from the Paleogene of Europe, North America and Asia. Since the early years of verte-brate palaeontology (e.g., Gilmore, 1928; Marsh, 1871, 1872) and continuing up to the twenty-first century (e.g., Augé, 2005; Čerňanský et al., 2023c; Meszoely et al., 1978; Smith, 2009a; Sullivan & Augé, 2006; Sullivan & Dong, 2018; Sullivan, 1979b, 2019), frontals have been invoked to diagnose taxa. Hence, we conducted an exten-sive comparison of MHNT.PAL. 2023.0.31.114 to frontals of known glyptosaurines.

The holotype (MHNT.PAL. 2023.0.31.114) can be dif-ferentiated from the Asian *Stenoplacosaurus* in having: (1) fused frontals; (2) fewer cranial osteoderms; and (3) flat anterior osteoderms (bulbous in *Stenoplacosaurus*).

The holotype (MHNT.PAL. 2023.0.31.114) can also be differentiated from *Placosaurus estesi* Sullivan & Augé, 2006, and (the type species of the genus) *Placosaurus rugosus* Gervais, 1848–1852 (both found in the Quercy Phosphorites; Sullivan, 2019) on the same features, except for the fused frontals.
The holotype (MHNT.PAL. 2023.0.31.114) can further-
more be differentiated from all *Placosaurus* in having: (1)
a central osteoderm as the anteriormost osteoderms (in
*Placosaurus* the first lateral osteoderms border the first
central osteoderm anteriorly; Sullivan & Augé, 2006); and
(2) the anterior portion of the frontals narrower (one or
no osteoderm between the lateral rows vs. two or more
osteoderms between the lateral rows in *Placosaurus*).

The holotype (MHNT.PAL. 2023.0.31.114) differs from
the North American *Glyptosaurus, Eoglyptosaurus, and
Helodermoides* in having: (1) fewer rows of osteoderms
between the orbits; (3) flat anterior osteoderms (bulbous
in the North American genera; Sullivan, 1979a, 1979b);
and (4) a narrower frontal (one or no osteoderm between
the lateral rows vs. two or more osteoderms between the
lateral rows in North American glyptosaurine). It differs
additionally from *Helodermoides* in having a concave lat-
eral margin of the frontal (straight in *Helodermoides*; see
Sullivan, 1979b).

The holotype (MHNT.PAL. 2023.0.31.114) can also
be differentiated from *Gaultia* (with its two species,
the North American *Gaultia silvaticus* Smith, 2009a,
and the Belgian *Gaultia ragei* [Sullivan et al., 2012]; see
Čerňanský et al., 2024) in having: (1) a pattern of polyg-
onal-shaped osteoderms (presence of chevron like lateral
osteoderms in *Gaultia*); and (2) tubercles organized in a
radiate pattern.

Lastly, the holotype (MHNT.PAL. 2023.0.31.114)
resembles *Sullivanosaurus* Čerňanský, Tabuce & Vid-
alenc, 2023d, in having: (1) a pattern of polygonal shaped
osteodermal shields; (2) a single row of central osteo-
derms; (3) fewer rows of osteoderms between orbits than
most glyptosaurines (in particular *Placosaurus* and *Glyp-
tosaurus*); and (4) a concave lateral margin. However, it
does differ from *Sullivanosaurus gallicus* (Čerňanský
et al., 2023c), in having: (1) the first central osteo-
derm diamond-shaped (leaf-shaped in *S. gallicus*; see
Čerňanský et al., 2023c); and (2) the tubercles arranged
on each osteoderm in a radiate pattern. Additional dif-
ferences on the osteoderm pattern might be linked to
missing anterior osteoderm in the holotype MHNT.PAL.
2023.0.31.114.

To recapitulate, the holotype MHNT.PAL.
2023.0.31.114 represents a glyptosaurid with a unique
pattern of irregularly shaped cephalic osteoderms cov-
ering the fused frontals, with the first central osteo-
derm being diamond-shaped and very anterior (half its
length) to the first lateral osteoderms, the latter in con-
tact medially (thus separating the first and second cen-
tral osteoderms). It can also be differentiated from all
other glyptosaurids by the following characters combina-
tion: (1) anterior osteoderms flat (as in *Sullivanosaurus*,
*Gaultia*, *Placosauriops*, *Peltosaurus*, and *Paraxestops*,

but also more primitive taxa like *Odaxosaurus* Gilmore,
1928, and *Proxestops* Gauthier, 1982); (2) posterior osteo-
derms becoming “bumpier” (as in *Gaultia* and *Glypto-
saurus rhodinos* Smith, 2011b); (3) fewer osteoderm rows
between the orbits than most glyptosaurines (contra *Pla-
cosaurus*); (3) an ornamentation made of small tubercles
arranged in a radiate pattern around the center of each
osteoderm (as in *Placosaurus*, *Glyptosaurus*, *Eoglypto-
saurus*, and *Helodermoides*); (4) concave lateral margin of
the frontal (unlike *Helodermoides*) and (5) fused frontals
(unlike in *Stenoplacosaurus*). Thus, MHNT.PAL.
2023.0.31.114 represents a new taxon of Glyptosaurinae
from the late Eocene of Quercy, which we here establish
as *Cadurcopanoplos vaylatsensis* gen. et sp. nov.

*Description of the tentatively referred mandible* **UM-BFI 3070.** UM-BFI 3070 is a partial right mandible.

The dentary is almost completely preserved, missing
only its anterior region (Fig. 15a, b, d). The dentary is
massively built (Fig. 15). The external surface is smooth
(Fig. 15b). A series of at least two labial foramina is pre-
served (Fig. 15b, a third one might be present, but it is
difficult to assess due to poor preservation). A deep ovoid
alveolar foramen opens lingually (Fig. 15a) with its poste-
rior margin made by the surangular (Fig. 15a). The intra-
mandibular septum runs in a dorsomedial-ventrolateral
direction, with a deep notch at the level of the alveolar
foramen (Fig. 15a, e). The ventral margin of the septum
is divided from the ventral wall of the dentary by a shal-
low groove (Fig. 15a). The sulcus Meckeli is open ven-
trolingually on its entire length but narrows anteriorly
(Fig. 15a). The dentition is poorly preserved, with four
teeth and six additional tooth positions (Fig. 15c). All
teeth have a broad base, with a rounded apex without any
cusp (Fig. 15f; although this might be linked to poor pres-
ervation). The posteriormost teeth are enlarged (Fig. 15f).
A small portion of the surangular is preserved (Fig. 15a).
The preserved portion is overlapped by the intramandib-
ular septum dorsally (Fig. 15a, e). The anterior margin of
the surangular is deeply notched (posterior margin of the
alveolar foramen).

*Attribution and remarks of the tentatively referred mandible UM-BFI 3070.* The fusion of the ventral margin of the intramandibular septum to the floor of the sulcus Meckeli, the well-developed alveolar foramen and the size of the dentary are features observed in both *Placosaurus* and *Parapacosauriops* (Augé, 2005; Augé & Sullivan, 2006; Georgalis et al., 2021a). However, the dentary UM-BFI 3070 differs from *Parapacosauriops* in lacking the cutting edge on the teeth’s apex (Augé & Sullivan, 2006; Georgalis et al., 2021a). It also differs from *Placosaurus* in: (1) having the posterior teeth enlarged (Augé, 2005). It is impossible to assess whether these differences regarding the absence of striation and cutting edges in
<figure><img src="image_19.png" /><figcaption>**Fig. 16** Glyptosauridae indet. from La Bouffie, Premaxilla (MHNT.PAL. 2023.0.31.121) in anterior (**a**), posterior (**b**), and left lateral (**c**) views. **af**, anterior foramen; **spd**, supradental shelf; **vpr**, vomerine process.</figcaption></figure>

<figure><img src="image_20.png" /><figcaption>**Fig. 17** Glyptosauridae indet. from La Bouffie, osteoderms. Cephalic osteoderms (**a-g**): **a-b**, UM-BFI 3089 in dorsal (**a**) and lateral (**b**) views; **c-d**, UM-BFI 3113 in dorsal (**c**) and ventral (**d**) views; **e-f**, UM-BFI 3096 in dorsal (**e**) and lateral (**f**) views; **g**, UM-BFI 3120 in dorsal view. **h-t** Trunk osteoderms: **h-i**, UM-BFI 3112 in dorsal (**h**) and ventral (**i**) views; **j-l**, UM-BFI 3076 in dorsal (**j**), lateral (**k**), and ventral (**l**) views; **m**, UM-BFI 3097 in dorsal view; **n-p**, UM-BFI 3056 in dorsal (**n**), lateral (**o**), and ventral (**p**) views; **q**, UM-BFI 3078 in dorsal view; **r**, UM-BFI 3080 in dorsal view; **s**, UM-BFI 3094 in dorsal view; **t**, UM-BFI 3145 in dorsal view</figcaption></figure>
UM-BFI 3070 are natural or simply due to the poor preservation or weathering. Nevertheless, taking into consideration that we here described a new genus and species from La Bouffie, characterized with unique frontal morphology, it is plausible that this dentary could also belong to the same taxon. We thus tentatively assign UM-BFI 3070 to *Cadurcopanoplos vaylatsensis* gen. et sp. nov.

**Glyptosauridae indet.**

Figures 16, 17

*Material.* One incomplete premaxilla (MHNT.PAL. 2023.0.31.121); nine cephalic osteoderms (MHNT.PAL. 2023.0.31.113a– MHNT.PAL. 2023.0.31.113f, UM-BFI 3089, UM-BFI 3113, and UM-BFI 3120); 16 trunk osteoderms (MHNT.PAL. 2023.0.31.113a– MHNT.PAL. 2023.0.31.113c, UM-BFI 3056, UM-BFI 3076, UM-BFI 3078, UM-BFI 3080, UM-BFI 3094, UM-BFI 3097, UM-BFI 3111, UM-BFI 3112, UM-BFI 3142, UM-BFI 3145, UM-BFI 3146, UM-BFI 3176, and UM-BFI 3177).

*Description*

**Premaxilla:** MHNT.PAL. 2023.0.31.121 preserves most of the right portion a premaxilla (Fig. 16a-c). Four teeth are preserved, and the complete premaxilla likely had 7-8 (Fig. 16a, b). There is no enlarged central tooth (vs. condition present in amphisbaenian), and all teeth share the same morphology, straight with a lateromedially compressed apex (Fig. 16b). The vomerine process is thick and prominent (Fig. 16b, c). The supradental shelf is well developed (Fig. 16b, c). Two large anterior foramina open anteriorly (Fig. 16a).

**Osteoderms:** 25 tuberculated osteoderms were available in our sample: nine are hexagonal or otherwise polygonal (Fig. 17a-g) and 16 are rectangular (Fig. 17h-t). The former represent cephalic osteoderms, while the latter are from the trunk region (e.g., Gauthier, 1982). Cephalic osteoderms have more prominent tubercles, arranged in a circular pattern from the center of the osteoderm (Fig. 17a, c, e). Trunk osteoderms bear a smooth gliding surface located anteriorly (Fig. 17h, j, q, r, t). The ventral surface of all osteoderms is pierced by several, irregularly placed, foramina (Fig. 17d, i, l).

**Attribution and remarks.** The premaxilla (MHNT.PAL. 2023.0.31.121) resembles premaxillae previously assigned to European glyptosaurids (*Placosaurus* and *Paraplacosauriops*) in: (1) the number of teeth; (2) the presence of two anterior foramina on each side; (3) mediolaterally compressed teeth; and (4) its overall size. The osteoderms are assigned to Glyptosauridae because they possess the typical tuberculated ornamentation (Čerňanský et al., 2023c, 2024; Estes, 1983; Gauthier, 1982). Unfortunately, both premaxillae and osteoderm do not usually bear enough diagnostic features for a more precise taxonomic determination within glyptosaurids,

though it is likely (but not certain) that these could perhaps as well to the above-described taxon *Cadurcopanoplos vaylatsensis* gen. et sp. nov.

Anguidae Gray, 1825

Anguinae Gray, 1825

Anguinae indet.

Figure 18

*Material.* Seven trunk vertebrae (UM-BFI 3077, UM-BFI 3088, UM-BFI 3132, UM-BFI 3136, UM-BFI 3192, UM-BFI 3194, and UM-BFI 3196); and one caudal vertebra (UM-BFI 3172).

*Description.* UM-BFI 3077 is a trunk vertebra, missing the right prezygapophysis and the anterior portion of the neural arch (Fig. 18a-e). The centrum is procoelous, with a dorsoventrally compressed cotyle and condyle (i.e., wider than high; Fig. 18a, b). Its ventral surface is flat, with no haemal keel visible (Fig. 18d). The centrum is elongated anteroposteriorly (Fig. 18c). The neural canal is arched and taller than the cotyle (Fig. 18a). The neural arch has a marked interzygapophyseal constriction (Fig. 18c). The prezygapophysis bears an ovoid articular facet extended anteriorly (Fig. 18c). The facet is oriented dorsomedially (Fig. 18a). The subcentral ridges of the centrum are concave (Fig. 18d). A thin dorsal ridge extends on the neural arch on its entire length (Fig. 18c). Posteriorly, it thickens into a short neural spine (Fig. 18c, e). UM-BFI 3132 is identical to UM-BFI 3077 but is poorly preserved (Fig. 18f-j). UM-BFI 3192 and UM-BFI 3196 are also similar to UM-BFI 3077.

UM-BFI 3088 (Fig. 18k-o) and UM-BFI 3136 (Fig. 18p-t) are similar to UM-BFI 3077 and UM-BFI 3132, with the exception of the following characters: (1) articular facet of the prezygapophyses less extended anteriorly; (2) shorter and wider centrum; and (3) shorter neural spine (likely linked to a poorer preservation). UM-BFI 3194 is also similar to UM-BFI 3088 and UM-BFI 3136.

UM-BFI 3172 (Fig. 18u-w) is a caudal vertebra missing most of its neural arch. The vertebra is similar to the trunk vertebrae on the following characters: (1) cotyle and condyle wider than high; (2) relatively smooth ventral surface of the centrum; and (3) neural arch not vaulted. The para- and diapophyses are fused into a large pleurapophysis, extending laterally (Fig. 18u-w).

**Attribution and remarks.** All these specimens are referred to Anguinae based on the following characters: (1) cotyle and condyle depressed; (2) flattened ventral surface of the centrum; and (3) neural arch not very vaulted posteriorly (Augé, 2005; Meszoely, 1970; Rage & Augé, 2015). Note that the two former characters are also present in the North American related group *Anniellinae* (Bell et al., 1995; Meszoely, 1970; Smith, 2011a). In any case, a taxonomic identification below the family
<figure><img src="image_21.png" /><figcaption>**Fig. 18** Anguinae indet. from La Bouffie. Anguinae indet. morphotype 1 (a–j): a–e, trunk vertebra (UM-BFI 3077) in anterior (a), posterior (b), dorsal (c), ventral (d), and left lateral (e) views; f–j, trunk vertebra (UM-BFI 3132) in anterior (f), posterior (g), dorsal (h), ventral (i), and left lateral (j) views. Anguinae indet. morphotype 2 (k–t): k–o, trunk vertebra (UM-BFI 3088) in anterior (k), posterior (l), dorsal (m), ventral (n), and right lateral (o) views; p–t, trunk vertebra (UM-BFI 3136) in anterior (p), posterior (q), dorsal (r), ventral (s), and left lateral (t) views; Anguinae indet. (unknown morphotype): u–w, caudal vertebra (UM-BFI 3172) in dorsal (u), ventral (v), and posterior (w) views</figcaption></figure>

level in pre-Miocene anguines is difficult when based on non-cranial elements, as several genera were present during the Paleogene of Europe and for certain of these vertebrae are so far unknown (Augé, 2005; Čerňanský et al., 2016a; Georgalis et al., 2021a, 2021b; Klembara & Green, 2010; Vasilyan et al., 2022) and variation within the vertebral column can be high (Georgalis & Scheyer, 2021). It should be noted that UM-BFI 3077, UM-BFI 3132, UM-BFI 3192, and UM-BFI 3196 represent an

*Ophisaurus*-like morphotype vertebra, with: (1) sub-central ridges concave; and (2) height of the neural canal taller than the cotyle (see Čerňanský et al., 2019). As UM-BFI 3088, UM-BFI 3136, and UM-BFI 3194 differ from UM-BFI 3077 on these features, they could potentially represent a second anguine taxon from La Bouffie, but it is impossible to assess this based on such limited amount of isolated vertebrae, while admittedly, we cannot exclude that these differences can be merely
attributed to some (unknown degree of) intracolumnar variation. The genus *Ophisaurus* Daudin, 1803, has been mentioned (on non-illustrated materials) from La Bouffie (Crochet et al., 1981; later mentioned only as Anguinae indet. in Augé, 2005). These being said, we consider these genus-level identifications of Crochet et al. (1981) to be unfounded, pending the discovery of cranial elements from La Bouffie.

**Helodermatidae Gray, 1838**

*Eurheloderma Hoffstetter, 1957*

*cf. Eurheloderma sp.*

Figure 19

*Material.* One left dentary (UM-BFI 3087).

**Description.** UM-BFI 3087 preserves most of the posterior region (Fig. 19). The dentition is almost identical to the maxilla assigned to *Palaeovaranus* (see also below). The ventral region of the dentary is not preserved, but the sulcus Meckeli is fully opened ventrally and lingually (Fig. 19a, b). It narrows anteriorly by the expansion of the dental shelf (Fig. 19a, b). Posterior to the tooth row, the coronoid process and articulation is small. The intramandibular septum is preserved with a short but thick posterior spine (Fig. 19a, b; “eminence” in Bhullar & Smith, 2008). On the labial surface, labial foramina pierce the dentary’s mid-length (Fig. 19f, j).

**Attribution and remarks.** Three large lizards with teeth exhibiting developed plicidentine folds are present in the Eocene of the Quercy Phosphorites, i.e., *Eurheloderma*, *Palaeovaranus*, and *Saniwa* Leidy, 1870. Among them, *Palaeovaranus* and *Eurheloderma* both exhibit a distinct posterior spine on the intramandibular septum (Bhullar & Smith, 2008; Georgalis et al., 2021a). However, the posterior spine in UM-BFI 3087 is thicker than the one observed in *Palaeovaranus* (see Georgalis et al., 2021a: fig. 46) and in fact, resembles more the one in *Eurheloderma* (see figs. in Hoffstetter, 1957; see also figs. of helodermatid dentaries in Bhullar & Smith, 2008). Indeed, a similar prominent structure (“eminence”) can be observed in Miocene and extant North American helodermatids (e.g., Bhullar & Smith, 2008: figs. 1, 6) and one paratype dentary (MNHN.FQU17596) of *Eurheloderma gallicum* (Krister Smith, personal communication; GLG, personal observation – note though that this structure is not clearly discernible in the published drawing of Hoffstetter [1957: fig. 3A], but it is prominent in the actual specimen). As a further note, we remark that a somehow prominent eminence of the intramandibular septum is also observed in a dentary (NHMW 2019/0058/0054) previously described and figured by Georgalis et al., (2021a: figs. 46–47) from the “old collections” of Quercy, which they attributed to *Palaeovaranus*;

<figure><img src="image_22.png" /><figcaption>**Fig. 19** cf. *Eurheloderma* sp. from La Bouffie. Left dentary (UM-BFI 3087) in lingual (a), ventrolingual (b), labial (c), dorsal (d), and posterior (e) views</figcaption></figure>
nevertheless, the coronoid articulation of NHMW 2019/0058/0054 is much different than that of UM-BFI 3087. In the current state of knowledge, it is difficult to assess if this eminence is unique to *Eurheloderma* (and thus NHMW 2019/0058/0054 would be a helodermatid and not a palaeovaranid) or whether it is more variable among large Eocene anguimorphs. Thus, we tentatively assign UM-BFI 3087 to cf. *Eurheloderma*.

**Palaeovaranidae Georgalis, 2017**

*Palaeovaranus Zittel, 1887–1890*

*Palaeovaranus* sp.

Figures 20, 21, 22

*Material*. One left maxilla (UM-BFI 3055); one trunk vertebra (UM-BFI 3131); and eight caudal vertebrae (UM-BFI 3133, UM-BFI 3138, UM-BFI 3140, UM-BFI 3149, UM-BFI 3184, UM-BFI 3195, UM-BFI 3199, and UM-BFI 3203).

*Description*

**Maxilla:** UM-BFI 3055 is a left maxilla missing most of its posterior medial portions (Fig. 20a-c). The two preserved teeth have a mesiodistally broad base, and their shafts are curved posteriorly (Fig. 19a). Plicidentine folds are well developed (Fig. 20a). The nasal process gradually increases in height posteriorly (Fig. 20a). The supradental shelf is thin and projects lingually (Fig. 19a). Anterodorsal to the supradental shelf, the basal torus (Georgalis et al., 2021a) is visible medially (Fig. 20a, b). Posterior to the basal torus, the anterior region of the lacrimal recess is shallow and pierced by an open foramen (Fig. 20b). There seems to be an articulation facet, perhaps for the vomer ("oblique internasal lamella" in Georgalis et al., 2021a, 2021b, 2021c; this feature could be taxonomically informative, but a broader comparison to maxillae of other anguimorphs is needed). The labial surface of the maxilla is pierced by two labial foramina, approximately at the level of the supradental shelf (Fig. 20c).

**Trunk vertebra:** The single available trunk vertebra (UM-BFI 3131) is rather large (7 mm centrum length). The centrum is procoelous, longer than the neural arch and widens anteriorly (Fig. 21). The cotyle is very depressed (Fig. 21a). The neural arch is slightly vaulted, and the neural spine is broken near its base (Fig. 21e). The ventral surface of the centrum bears two distinct ridges (Fig. 21d).

**Caudal vertebrae:** The description is based on the best-preserved vertebra, UM-BFI 3133, as the other six are rather incomplete (Fig. 22). The vertebra is very elongated anteroposteriorly and slender (Fig. 22c, d, e). The cotyle is not depressed and is wider than tall (Fig. 22a). The prezygapophyses are strongly inclined dorsomedially, with an articular facet extending dorsolaterally (Fig. 22a, c). The neural spine is tall and found at the posterior end of the neural arch only (Fig. 22c, e). However, it does extend up to the anterior margin of the neural arch as a thin and low neural ridge (Fig. 22c). No autotomic septum is present (Fig. 22d). On the ventral surface of the centrum, an hourglass-shaped groove extends medially on the entire length of the centrum, flanked by two lateral ridges (Fig. 22d). On the posterior margin of the ventral surface, two thick pedicellate facets for the chevrons are visible (Fig. 22d).

**Attribution and remarks.** The dentition, consisting of large, subpleurodont, curved teeth is reminiscent of three large lizards from the Eocene of the Quercy, *Eurheloderma*, *Palaeovaranus*, and *Saniwa* (see Augé, 2005; Georgalis & Scheyer, 2019; Georgalis et al., 2021a; Čerňanský et al., 2024). Two of them, *Eurheloderma* and *Palaeovaranus*, have been mentioned from this locality (Augé, 2005; Georgalis et al., 2021a). In *Palaeovaranus*, the nasal process moderately increases in height posteriorly and bears a distinctly developed nasal crest on its dorsomedial surface (Georgalis et al., 2021a). UM-BFI 3055 does not preserve the dorsal region of the maxilla, so the first character cannot be assessed. However, it

<figure><img src="image_23.png" /><figcaption>**Fig. 20** *Palaeovaranus* sp. from La Bouffie, cranial element. **a–c**, incomplete left maxilla (UM-BFI 3055) in lingual (**a**), dorsal (**b**), and labial (**c**) views</figcaption></figure>
<figure><img src="image_24.png" /><figcaption>**Fig. 21** *Palaeovaranus* sp. from La Bouffie, trunk vertebra. Trunk vertebra (UM-BFI 3131) in anterior (a), posterior (b), dorsal (c), ventral (d), and left lateral (e) views</figcaption></figure>
<figure><img src="image_25.png" /><figcaption>**Fig. 22** *Palaeovaranus* sp. from La Bouffie, caudal vertebra. Caudal vertebra (UM-BFI 3133) in anterior (a), posterior (b), dorsal (c), ventral (d), and left lateral (e) views</figcaption></figure>
does exhibit a moderate increase in height of the nasal process (i.e., exhibits a low angle of rise of the nasal process). This is indeed more consistent with *Palaeovaranus*, unlike *Saniwa orsmaelensis* Dollo, 1923, where the increase is less steep, and *Eurheloderma gallicum*, where the increase is very steep; different degrees of the rise of the nasal process are also observed in the two Eocene German palaeovaranids, *Eosaniwa* Haubold, 1977, from Geiseltal and *Paranecrosaurus* Smith & Habersetzer, 2021, from Messel (see Hoffstetter, 1957; Haubold, 1977; Augé, 2005; Georgalis et al., 2021a; Smith & Habersetzer, 2021; Augé et al., 2022). The widely spaced infoldings of the tooth bases have also been considered a distinctive feature of palaeovaranids, compared to *Saniwa* and other varanids (see Čerňanský et al., 2024), with palaeovaranids possessing fewer infoldings per tooth compared to varanids (Smith & Habersetzer, 2021). Thus, UM-BFI 3055 is assigned to *Palaeovaranus* sp. The trunk vertebra UM-BFI 3131 does resemble vertebrae assigned to both Glyptosauridae and *Palaeovaranus* but is matches more to the palaeovaranid morphology in being more anteroposteriorly elongated (Georgalis et al., 2021a; see also Smith & Habersetzer, 2021). The seven caudal vertebrae are assigned to *Palaeovaranus* based on the following characters: (1) elongated and slender vertebra; (2) high neural spine on the posterior region of the neural arch; (3) presence of a medial groove and two lateral ridges on the ventral surface of the centrum; and (4) presence of a pedicellate facet for the chevrons (Georgalis & Scheyer, 2019; Georgalis et al., 2021a).

A single palaeovaranid species, *Palaeovaranus lismonimenos* Georgalis et al., 2021a, has been previously described from La Bouffie (Georgalis et al., 2021a). Nevertheless, the species-level identification among the two, so far, known valid species of *Palaeovaranus* is principally based on parietal morphology (see Georgalis et al., 2021a). Thus, we assign all these new elements from La Bouffie to *Palaeovaranus* sp.

**Anguimorpha indet.**

Figures 23, 24

*Material.* One dentary (UM-BFI 3075); one tooth bearing fragment (UM-BFI 3099); nine trunk vertebrae (UM-BFI 3134, UM-BFI 3139, UM-BFI 3180–UM BFI 3183, UM-BFI 3186, UM-BFI 3191, and UM-BFI 3206); and nine caudal vertebrae (UM-BFI 3143, UM-BFI 3144, UM-BFI 3148, UM-BFI 3186–UM BFI 3188, UM-BFI 3190, and UM-BFI 3204).

*Description*

**Dentary:** UM-BFI 3075 is a left dentary preserving most of its median region (Fig. 23a–c). Two recurved caniniform teeth with developed plicidentine folds are

preserved (Fig. 23a, b). The sulcus Meckeli is open ventrolingually (Fig. 23a).

**Trunk vertebrae:** The vertebra UM-BFI 3134 is large (6 mm centrum length). The centrum widens anteriorly (Fig. 23d, e, g). The cotyle is depressed and wider than the neural canal (Fig. 23d), The prezygapophyses are strongly inclined dorsally in anterior view (Fig. 23d) and anterolaterally in dorsal view (Fig. 23f). The neural arch is vaulted (Fig. 23h). The neural spine extends on the entire length of the neural arch, and overhangs past the posterior margin of the neural arch (Fig. 23f, h). The ventral surface of the centrum bears a wide and shallow medial keel on its anterior portion (Fig. 23g). UM-BFI 3182, UM-BFI 3183, UM-BFI 3191, and UM-BFI 3206 (Fig. 23i–m) resemble UM-BFI 3134.

UM-BFI 3139 and UM-BFI 3186 differ from UM-BFI 3134 in: (1) having a taller and wider neural canal, as wide as the cotyle (Fig. 23s–w); (2) a centrum wider anteriorly (twice the posterior width; Fig. 23v); and (3) a thin, well-marked medial keel on the entire ventral surface length (Fig. 23v). UM-BFI 3181 differs from all other vertebrae in having a broad well marked medial keel on its ventral surface (Fig. 24a–e).

**Caudal vertebrae:** All vertebrae are anteroposteriorly elongated, with a short neural spine projecting posteriorly (Fig. 24f–o). Their prezygapophyses are slightly expanded anterolaterally (Fig. 24h, m). The cotyle is flattened dorsoventrally, and the neural canal is not very high (Fig. h, m). Apart from UM-BFI 3143, remnants of fused neural arches are present on the ventral surface of all vertebrae, and an autotomy septum is present anteriorly (Fig. 24i, n). Some vertebrae (Fig. 24i) also exhibit a median keel on their ventral surface.

***Attribution and remarks.*** The dentary UM-BFI 3075 exhibits teeth with the same condition as UM-BFI 3055 (*Palaeovaranus*) and UM-BFI 3087 (cf. *Eurheloderma*). It lacks any diagnostic characters for either genus, thus can only be assigned to Anguimorpha indet.

Vertebrae UM-BFI 3134, UM-BFI 3181, UM-BFI 3182, UM-BFI 3183, UM-BFI 3191, and UM-BFI 3206 resemble the above vertebrae assigned to Anguinae indet. in: (1) having a depressed centrum but differ in: (1) having a vaulted neural arch; and (2) having a wide and shallow medial keel on its ventral surface. Furthermore, given the high intracolumnar variation observed in vertebrae of modern anguimorphs (e.g., for Anguinae, see Čerňanský et al., 2019), these vertebrae cannot be excluded from glyptosaurids or palaeovaranids. Thus, these are also assigned to an indeterminate anguimorph.

UM-BFI 3139 are interesting. The presence of a very large neural canal, a very wide centrum anteriorly and a thin medial keel, are reminiscent of “melanosaurine” and helodermatid vertebrae (Augé, 2005; Georgalis et al.,
<figure><img src="image_26.png" /><figcaption>**Fig. 23** Anguimorpha indet. from La Bouffie. **a–c**, Left dentary (UM-BFI 3075) in lingual (**a**), labial (**b**), and dorsal (**c**) views; **d–h**, trunk vertebra (UM-BFI 3134) in anterior (**d**), posterior (**e**), dorsal (**f**), ventral (**g**), and left lateral (**h**) views; **i–m**, trunk vertebra (UM-BFI 3180) in anterior (**i**), dorsal (**j**), ventral (**k**), right lateral (**l**), and (**m**) posterior views; **n–r**, trunk vertebra (UM-BFI 3206) in anterior (**n**), posterior (**o**), dorsal (**p**), ventral (**q**), and right lateral (**r**) views; **s–w**, trunk vertebra (UM-BFI 3139) in anterior (**s**), posterior (**t**), dorsal (**u**), ventral (**v**), and left lateral (**w**) views; **x–z**, trunk vertebra (UM-BFI 3186) in dorsal (**x**), ventral (**y**), and posterior (**z**) views</figcaption></figure>
<figure><img src="image_27.png" /><figcaption>**Fig. 24** Anguimorpha indet. from La Bouffie. **a–e**, trunk vertebra (UM-BFI 3206) in anterior (**a**), posterior (**b**), dorsal (**c**), ventral (**d**), and right lateral (**e**) views; **f–j**, caudal vertebra (UM-BFI 3144) in anterior (**f**), posterior (**g**), dorsal (**h**), ventral (**i**), and left lateral (**j**) views; **k–o**, caudal vertebra (UM-BFI 3187) in anterior (**k**), posterior (**l**), dorsal (**m**), ventral (**n**), and left lateral (**o**) views.</figcaption></figure>

2021a). They do seem to differ from known vertebrae of *Eurheloderma* in having a thin medial keel on the ventral surface of the centrum and lacking the comma-shaped parapophyses present in *Eurheloderma* (see Hoffstetter, 1957; Augé, 2005). The poorly preserved neural spine prevents an assignment to “Melanosaurinae”, and UM-BFI 3139 is thus assigned to an indeterminate anguimorph. It nevertheless seems to represent a further distinct taxon, other than the above-mentioned anguimorphs.

The caudal vertebrae present a mosaic of several features present in various anguimorph families: (1) cotyle compressed dorsoventrally; (2) haemal arches fused to the centrum; (3) short neural spine projecting posteriorly; (4) presence of an autotomy septum; and (5) presence of a median keel on the ventral surface of the centrum. Although some of these caudal vertebrae are reminiscent of palaeovaranids, the presence of an autotomic septum, precludes such taxonomic assignment, as these are absent from this group (Georgalis & Scheyer, 2019; Georgalis et al., 2021a; Smith & Habersetzer, 2021). On the other hand, autotomic septa have been documented in caudal vertebrae of glyptosaurids (Georgalis et al., 2021a, 2021b, 2021c; Rage, 1978), though still there are documented exceptions (e.g., Sullivan, 1979a). Thus,

we are reluctant to assign these specimens to a more precise taxonomic rank within Anguimorpha, and we cannot exclude they (or at least part of them) pertain to some of the above-described anguimorph taxa.

**Squamata** indet.

Figure 25

*Material.* Four left dentaries (UM-BFI 3062, UM-BFI 3179, UM-BFI 3084, and UM-BFI 3200); three right dentaries (MHNT.PAL. 2023.0.31.120, UM-BFI 3071, and UM-BFI 3093); one left lower jaw (UM-BFI 3205); two left maxillae (UM-BFI 3091, and UM-BFI 3150); two right maxillae (UM-BFI 3074, and UM-BFI 3092); three premaxillae (UM-BFI 3059, UM-BFI 3067, and UM-BFI 3086); and one trunk vertebra (UM-BFI 3137).

**Description and attribution**

**Dentaries and lower jaw:** The dentary UM-BFI 3093 preserves six teeth (Fig. 25a–c). Their crown is bicuspid with a small anterior accessory cusp and faint striations (Fig. 25a, b). Biscupid teeth are often present in Eocene lacertids, but this specimen from La Bouffie is too poorly preserved to warrant a more precise assignment. In UM-BFI 3179 (Fig. 25d–e), the dentition resembles a bicuspid condition, but this might also be linked to poor preservation. UM-BFI 3084 seems to have slender straight
<figure><img src="image_28.png" /><figcaption>**Fig. 25** Squamata indet. from La Bouffie. **a–c**, Right dentary (UM-BFI 3093) in labial (**a**), lingual (**b**), and dorsal (**c**) views; **d–e**, left dentary (UM-BFI 3179) in lingual (**d**) and labial (**e**) views; **f**, left dentary (UM-BFI 3084) in lingual view; **g–h**, right dentary (UM-BFI 3071) in lingual (**g**) and labial (**h**) views; **i–j**, right dentary (UM-BFI 3062) in lingual (**i**) and labial (**j**) views; **k–l**, left lower jaw (UM-BFI 3205) in lingual (**k**) and labial (**l**) views; **m–n**, left maxilla (UM-BFI 3091) in lingual (**m**) and labial (**n**) views; **o–q**, right maxilla (UM-BFI 3092) in lingual (**o**), labial (**p**), and ventral (**q**) views; **r**, left maxilla (UM-BFI 3150) in lingual view; **s–t**, premaxilla (UM-BFI 3059) in posterior (**s**) and anterior (**t**) views; **u–x**, premaxilla (UM-BFI 3067) in anterior (**u**), posterior (**v**), left lateral (**w**), and dorsal (**x**) views; **y–aa**, premaxilla (UM-BFI 3086) in anterior (**y**), right lateral (**z**), and posterior (**aa**) views; **ab–af**, trunk vertebra (UM-BFI 3137) in dorsal (**ab**), ventral (**ac**), left lateral (**ad**), anterior (**ae**), and posterior (**af**) views</figcaption></figure>

tricuspid teeth (Fig. 24f) but it cannot be more precisely assigned. The remaining dentaries (Fig. 25g–j) do not preserve any diagnostic characters that would warrant a more precise assignment within Squamata. The lower jaw (UM-BFI 3205) is very damaged (Fig. 25k, l). The lingual view does show the sulcus Meckeli opens ventrolingually, narrowing anteriorly (Fig. 25k). On its anterior region, the sulcus Meckeli opens lingually (Fig. 25k). This specimen cannot be more precisely assigned to any squamate group.

**Maxillae:** UM-BFI 3091 preserves three monocuspid teeth (Fig. 25m, n). UM-BFI 3092 preserves eight teeth, all broken before their apex (Fig. 25o–q). The teeth are slender and straight with resorption pits at their base (Fig. 25o). UM-BFI 3150 preserves two tricuspid teeth,

with faint accessory cusps (Fig. 25r). UM-BFI 3150 resembles maxillae traditionally assigned to pleurodontans (see e.g., Augé, 2005), but is too incomplete to warrant an assignment to a squamate group.

**Premaxillae:** UM-BFI 3067 is a premaxilla missing the dorsal portion of its nasal process and the right region of the bone (Fig. 25u–x). The element is unpaired (i.e., both premaxillae fused), with three teeth and one tooth position preserved (Fig. 25u, v). The teeth are straight and slightly broader at their base (Fig. 25u, v). They bear a slightly pointed, unicuspid apex, with striations (Fig. 25v). The nasal process is broad and has a straight lateral margin (Fig. 25u–w). The process is triangular in cross-section (Fig. 25x). A small notch is present at its base, delimiting a groove leading to two ethmoidal
foramina (opening laterally; Fig. 25w); anterior premaxillary foramina are absent. The posterior surface of the nasal process bears the base of a broad ridge that likely delimits the nasal articulations (Fig. 25w). Interestingly, the broad nasal process has been considered as a diagnostic feature of the genus *Geiseltaliellus*, however, it is now known that this character is more widespread within Pleurodonta (e.g., in *Suzanniwana* and some other Corytophanidae; see Smith, 2009a). The supradental shelf is divided into two sections, separated by a deep groove medially (Fig. 25v). The incisive processes are unfused (i.e., left and right processes separated by a deep groove medially; Fig. 25v) and moderately developed (Fig. 25v). The maxillary process is small, with a well-marked maxillary articulation facet dorsally (Fig. 25u, w). As a further note, if the left premaxillary process of UM-BFI 3067 is complete, it would seem to indicate an unusually complicated articulation with the maxilla, which could be taxonomically informative. Smith (2006, 2011a) documented an unusual articulation of the premaxilla with the maxilla in the extant polychrotid pleurodontan *Polychrus* Cuvier, 1817, and its fossil stem, in which the premaxilla overlaps the maxilla; it is not though certain whether something similar could happen in the La Bouffie premaxilla. These being said, it is possible that UM-BFI 3067 pertains to pleurodontans, but this taxonomic determination cannot be certain. UM-BFI 3059 (Fig. 25s, t) has a somehow similar morphology as UM-BFI 3067 but is very fragmentary.

UM-BFI 3086 is a very fragmentary premaxilla, with only part of the right region preserved (Fig. 25y-aa). Two teeth and one additional tooth position are preserved (Fig. 25y-aa). The teeth are small with a rounded apex (Fig. 25y), without any striations. The supradental shelf does not protrude posteriorly (Fig. 25z). Although broken, the vomerine and incisive processes are present (Fig. 25aa). The base of the nasal process is preserved and seems to widen dorsally (Fig. 25y). A small notch suggests an ethmoidal foramen is present (Fig. 25z). A small but well delimited maxillary facet is preserved on the dorsal surface. These three premaxillae represent two distinct taxa but cannot be securely assigned to a precise squamate group.

**Trunk vertebra:** The last specimen, UM-BFI 3137, is a small trunk vertebra (Fig. 25ab-af). The prezygapophyseal articular facets are small and circular (Fig. 25ab). A developed zygosphene and zygantrum are present (Fig. 25ac, ae). The neural arch is not very vaulted, and the neural spine is broken near its base (Fig. 25ad). The latter structure does extend on the entire length of the neural arch and overhang past the posterior margin of the neural arch (Fig. 25ab, ad). The centrum widens anteriorly, and the cotyle extends ventrally on the ventral surface of the centrum (Fig. 25ac). A developed median ridge is

present on the ventral surface of the centrum (Fig. 25ac). UM-BFI 3137 is also interesting. The presence of a true zygosphene-zygantrum complex is known in several lizard families (e.g., Pleurodonta, Teiidae, some large Lacertidae, and of course, snakes; Hoffstetter & Gasc, 1969; Szyndlar & Georgalis, 2023; Bourque & Stanley, 2025) present in La Bouffie. UM-BFI 3137 differs from the only trunk vertebra assigned to Tupinambinae from Quercy (specimen MNHN.F.PRR2006 from the MP 17 locality of Perrière; see Augé & Brizuela, 2020: fig. 5) in having a well-developed median ridge on the ventral surface of the centrum (vs. flattened centrum in MNHN.F.PRR2006) and being more elongated anteroposteriorly, however, it should be noted that both these features can be observed in extant tupinambines (see Bourque & Stanley, 2025).

## Discussion

### Herpetofaunal diversity from La Bouffie

In the original description of the fauna of La Bouffie (Crochet et al., 1981), 17 herpetofauna taxa had been listed, but these were not accompanied by any kind of illustration or description or collection numbers. Over the years, some of these identified taxa were eventually described and figured (Augé, 2005; Čerňanský & Auge, 2013; Georgalis et al., 2021a), and additional taxa were identified (Augé, 2005; Augé & Brizuela, 2020). A more recent taxonomic list of lizard taxa from La Bouffie (Augé & Brizuela, 2020) identified 14 taxa (contra six in Crochet et al., 1981), but most of them were not figured. Thus, since the work of Crochet et al (1981), no updated taxonomic list of the herpetofauna has been produced, and most of the taxa originally identified have not been described and figured.

Regarding amphibians, one urodele and four anurans were mentioned in the 1981 publication (Crochet et al., 1981). We confirm the presence of one urodele, an indeterminate salamandrid. The only specimen we were able to identify does not allow us to assess if the urodele from La Bouffie is a salamandrine or a pleuroderline (subfamilies of Salamandridae). For anurans, the presence of *Thaumastosaurus* is confirmed (Georgalis et al., 2023; Roček & Lamaud, 1995). All materials described in this study are not referred with certainty to *Thaumastosaurus bottii*, because osteological differences between species of this genus are still debated (Georgalis et al., 2023; Lemierre et al., 2021). It could be possible that more than one species of *Thaumastosaurus* inhabited La Bouffie. Nevertheless, until more complete materials are identified, we consider that a single species of *Thaumastosaurus*, *T. bottii*, is present in La Bouffie (Table 1).

The presence of pelobatids within the Eocene of the Quercy has been reviewed and revised in the last decades, following the reidentification of most cranial
<table><caption>**Table 1** Updated list of herpetofaunal taxa from La Bouffie. Taxa in bold represent taxa whose presence has been documented (specimens illustrated and described)</caption><thead><tr><th>Taxon</th><th>References</th></tr></thead><tbody><tr><td><strong>Urodela</strong></td><td></td></tr><tr><td>Salamandridae indet.</td><td>This study</td></tr><tr><td><strong>Anura</strong></td><td></td></tr><tr><td><em>Thaumastosaurus bottii</em></td><td>Roček &amp; Lamaud, 1995; Georgalis et al., 2023</td></tr><tr><td><em>cf. Pelodytes sp.</em></td><td>This study</td></tr><tr><td><strong>Gekkota</strong></td><td></td></tr><tr><td><em>Gekkota indet. 1</em></td><td>This study</td></tr><tr><td><em>Gekkota indet. 2</em></td><td>This study</td></tr><tr><td><strong>Lacertidae</strong></td><td></td></tr><tr><td><em>Plesiolacerta lydekkeri</em></td><td>Čerňanský and Auge, 2013</td></tr><tr><td><em>Lacertidae indet. 1</em></td><td>Augé, 2005; this study</td></tr><tr><td><em>Lacertidae indet. 2</em></td><td>Augé, 2005; this study</td></tr><tr><td><strong>Teiidae</strong></td><td></td></tr><tr><td><em>Tupinambinae indet.</em></td><td>Augé &amp; Brizuela, 2020</td></tr><tr><td><em>Brevisaurus smithi</em></td><td>Augé, 2005; Augé &amp; Brizuela, 2020</td></tr><tr><td><strong>Amphisbaenia</strong></td><td></td></tr><tr><td><em>Amphisbaenia indet.</em></td><td>This study</td></tr><tr><td><strong>Pleurodonta</strong></td><td></td></tr><tr><td><em>Cadurcuiana hoffstetteri</em></td><td>Augé, 2005; this study</td></tr><tr><td><em>Geiseltaliellus cf. lamandini</em></td><td>This study</td></tr><tr><td><em>aff. Pseudolacerta</em></td><td>This study</td></tr><tr><td><em>Phosphoriguana peritechne gen. et sp. nov</em></td><td>This study</td></tr><tr><td><strong>Glyptosauridae</strong></td><td></td></tr><tr><td><em>Cadurcopanoplos vaylatsensis gen. et sp. nov</em></td><td>This study</td></tr><tr><td><strong>Anguinae</strong></td><td></td></tr><tr><td><em>Anguinae indet.</em></td><td>This study</td></tr><tr><td><strong>Helodermatidae</strong></td><td></td></tr><tr><td><em>cf. Eurheloderma sp.</em></td><td>Augé, 2005, this study</td></tr><tr><td><strong>Palaeovaranidae</strong></td><td></td></tr><tr><td><em>Palaeovaranus lismonimenos</em></td><td>Georgalis et al., 2021a</td></tr><tr><td><strong>Anguimorpha</strong></td><td></td></tr><tr><td><em>Anguimorpha indet.</em></td><td>This study</td></tr><tr><td><strong>Serpentes</strong></td><td></td></tr><tr><td><em>Alethinophidia</em></td><td></td></tr><tr><td><em>"anilioid" indet. 1</em></td><td>G. Georgalis, unpublished data</td></tr><tr><td><em>"anilioid" indet. 2</em></td><td>G. Georgalis, unpublished data</td></tr><tr><td><strong>Constrictores</strong></td><td></td></tr><tr><td><em>Cadurceryx filholi</em></td><td>Szyndlar &amp; Georgalis, in review</td></tr><tr><td><em>Cadurcoboa</em></td><td>Georgalis, unpublished data</td></tr><tr><td><em>?Constrictores indet. 1</em></td><td>G. Georgalis, unpublished data</td></tr><tr><td><em>?Constrictores indet. 2</em></td><td>G. Georgalis, unpublished data</td></tr></tbody></table>

elements as *Thaumastosaurus* (Georgalis et al., 2023; Rage, 2016). Thus, until the identification of postcranial elements is made available, pelobatids cannot be identified in La Bouffie. Lastly, we confirm the presence of Pelodytidae, originally mentioned in Crochet et al.

(1981). They are referred to as cf. *Pelodytes*, following Rage (2016). Thus, the revised amphibian fauna from La Bouffie is composed of at least three taxa: an indeterminate salamandrid, cf. *Pelodytes*, and *Thaumastosaurus bottii*.
Lizards are diverse in the La Bouffie assemblage, with at least 16 distinct species identified. We confirm the presence of gekkotans, with two indeterminate forms identified (Table 1). However, based on the material currently available, we cannot confirm the presence of *Cadurcogekko piveteaui* Hoffstetter, 1946, as was suggested in the faunal list of Augé and Brizuela (2020). Interestingly, our sample witnesses the coexistence of both amphicoeolous and procoelous gekkotan vertebrae.

The small lacertid *Gracilicerta* has been mentioned in previous studies (Augé, 2005; Augé & Brizuela, 2020). However, we cannot confirm its presence based on the material currently available. Nevertheless, two small indeterminate lacertid forms are present in La Bouffie (Table 1). A third lacertid, the large species *Plesiolacerta lydekkeri* Hoffstetter, 1942, was also mentioned by Čerňanský and Auge (2013), but that material was not figured. The lacertoid *Brevisaurus smithi* Augé, 2005, originally described as a teiid by Augé (2005) upon material from the “old collections” of Quercy, has also been mentioned from La Bouffie (Augé, 2005; Augé & Brizuela, 2020), but has not been figured nor described, so its presence cannot be confirmed. However, isolated elements assigned to an indeterminate tupinambine (subfamily of Teiidae) and different from *Brevisaurus* Augé, 2005, have been recently illustrated and described from La Bouffie (Augé & Brizuela, 2020), confirming the presence in Europe of this South American family during the late Eocene (Augé & Brizuela, 2020).

Amphisbaenians were present in La Bouffie, as is attested by the two vertebrae described above. Crochet et al. (1981) had mentioned in their original list the presence of the family Amphisbaenidae from La Bouffie; nevertheless, the taxonomic concept of Amphisbaenidae has drastically changed since the 1980's and the group as currently circumscribed is not and was never present in Europe, while besides, as it was explicitly stated above, amphisbaenian vertebrae are difficult or impossible to refer to the family level.

The diversity of pleurodontans from La Bouffie is greatly expanded. In the original documentation of the locality, only the large *Pseudolacerta* was mentioned (Crochet et al., 1981). A second pleurodontan taxon, *Cadurciguana*, was added later, but no specimens were figured (Augé, 2005). In the more recent taxonomic list of La Bouffie, only *Cadurciguana* was mentioned (Augé & Brizuela, 2020). We herein confirm the presence of *Cadurciguana*. Two specimens are assigned to *aff. Pseudolacerta*, but the presence of this genus is still uncertain. To these two taxa, a third pleurodontan taxon, *Geiseltaliellus cf. lamandini*, is also identified from La Bouffie. It should be noted that *Geiseltaliellus lamandini* was originally placed within *Pseudolacerta* (Augé,

2005; but see Smith, 2009b on the uncertainty of that genus level placement) and original identification could have been obtained on elements referrable to *G. lamandini*. Lastly, a new genus of a likely pleurodontan lizard is identified, *Phosphoriguana* nov. This new genus represents a very distinct morphology of dentary, with a curved ventral margin (unlike *Cadurciguana* and *Geiseltaliellus*) and a lingually opened sulcus Meckeli (like *Pseudolacerta*, but it lacks the enlarged caniniform anterior teeth; Augé, 2005). It shows that pleurodontans were highly diversified in the Eocene in Europe, with five genera and at least eight species.

The Eocene glyptosaurid *Placosaurus* has been previously mentioned from La Bouffie on the basis of trunk and caudal vertebrae, as well as osteoderms (Augé, 2005), however, none of these were ever figured or described. Vertebrae have been used in several studies to identify *Placosaurus* (Georgalis et al., 2021a; Rage, 1978, 1988, 2012; Rage & Augé, 2010). However, it is not possible to assess if any of the new glyptosaurids described in the recent years (e.g., Čerňanský et al., 2023c, 2024; this study) had similar or different vertebral morphology than *Placosaurus*. Thus, we consider that specimens previously referred to *Placosaurus* from La Bouffie should be better considered as Glyptosaurinae indet., with an even more plausible identification as belonging to the new taxon *Cadurcopanoplos vaylatsensis* gen. et sp. nov., which is established herein from this locality, based on frontal material and perhaps also a lower jaw. Furthermore, the presence of an additional glyptosaurine genus in the late Eocene of the Quercy Phosphorites indicates that future identifications in these localities should be better made using cranial elements (as they preserve the osteoderm pattern) rather than postcranial elements, likely not diagnostic below the subfamily (or perhaps even family) level.

For Anguinae, the original description identified one genus, *Ophisaurus* (Crochet et al., 1981; also present in Augé & Brizuela, 2020). However, taxonomic assignment of Paleogene isolated vertebrae to the genus level has been considered highly uncertain (Klemba & Green, 2010; Čerňanský et al., 2016a, 2016b; Georgalis et al., 2021a). Thus, we refute previous identifications of *Ophisaurus* by Crochet et al (1981). Based on our illustrated specimens, more than one species of anguines could eventually have been present in La Bouffie, though as we highlighted above, we cannot exclude that the differences among our specimens were not simply due to intracolumnar variation.

The helodermatid *Eurheloderma* has been previously identified from La Bouffie on the basis of trunk and sacral vertebrae (Augé, 2005: figs. 182–183). Our herein illustrated dentary UM-BFI 3087 (Fig. 19) tentatively
supports the presence of this genus. The genus *Palaeo-varanus* had been originally mentioned (*Necrosaurus cayluxi* of Crochet et al., 1981), and up to two palaeovaranid species had been mentioned from La Bouffie (Augé & Brizuela, 2020). However, subsequent revision of *Palaeovaranus* has reassigned the cranial material from La Bouffie to a single species, *Palaeovaranus lismonimenos* (see Georgalis et al., 2021a). Our cranial and vertebral material described herein from La Bouffie could likely also belong to *Palaeovaranus lismonimenos*, however, as parietals (that possess the species level diagnostic characters for this genus) are not available in our sample, we simply attribute our specimens to *Palaeovaranus* sp.

Finally, the snakes of La Bouffie have not been revised since the original mentions presented in Crochet et al. (1981), especially as several genera from Quercy have been redefined since (Georgalis et al., 2021c; Smith & Georgalis, 2022; Szyndlar & Rage, 2003). Some of the specimens are currently being revised by one of us (GLG), and *Cadurceryx*, *Cadurcoboa*, at least two “anil-ioids” and two Constrictores (sensu Georgalis & Smith 2020) (GLG., unpublished data) have been identified. However, the taxonomic assignment nor precise number of snake taxa cannot be currently assessed.

Thus, the herpetofauna of La Bouffie is currently comprised of 18 described and figured taxa (Table 1). The presence of eight additional taxa cannot be confirmed (Table 1). As such, La Bouffie yields almost half of the current herpetofauna diversity from the MP 17 in Europe (Augé, 2005; Georgalis et al., 2021a; Rage, 2006, 2012) and is one of the most diverse late Eocene localities from the Quercy, with the slightly older locality of Le Bretou (23–24 taxa, MP 16; Rage, 1978). It is also one of the most diverse localities in Europe for the late Eocene.

## Glyptosauridae diversity in the Eocene and patterns of ornamentation

With the newly described *Cadurcopanoplos vaylatsensis* gen. et sp. nov., at least nine valid species have been so far referred to Glyptosauridae in the Eocene of Europe (Čerňanský et al., 2023c, 2024). *Cadurcopanoplos* gen. nov. is also the first non-*Placosaurus* glyptosaurine from the late Eocene, which suggests that this subfamily was more diverse than previously thought. The pattern of ornamentation and osteoderm morphology of *Cadurcopanoplos* gen. nov. is also very interesting. A clear difference exists between early Eocene glyptosaurines and post-early Eocene glyptosaurines in Europe (as mentioned already in Čerňanský et al., 2023c, 2024). In both *Gaultia ragei* and *Sullivanosaurus gallicus*, the osteoderms are apically flat, irregular in shape and size, with small tubercles densely arranged (Čerňanský et al., 2023c, 2024), while *Placosaurus* is characterized by thick,

hexagonal and sub-equal osteoderms, with small tubercles arranged in a radiate pattern around the center of the osteoderm (Sullivan & Augé, 2006). *Cadurcopanoplos* gen. nov., with its irregular shaped osteoderms, clearly resembles glyptosaurines from the early Eocene, and a close morphological relationship between *Gaultia*, *Sullivanosaurus*, and the new genus from La Bouffie cannot be ruled out. This suggests that glyptosaurines from the late Eocene retained several characteristics from their older “ancestors”. This also implies that glyptosaurines with hexagonal / polygonal osteoderms (such as *Placosaurus*, *Glyptosaurus*, *Eoglyptosaurus*, *Helodermoides*, and *Stenoplacosaurus*) are more derived than *Cadurcopanoplos* gen. nov. Interestingly, *Gaultia* and *Sullivanosaurus* have been considered to represent an “intermediate” stage of osteoderm break-up, between the plate-like osteoderms of primitive anguioids and the hexagonal osteoderm of late Eocene and Oligocene glyptosaurines (Čerňanský et al., 2023c; Smith, 2009a). *Cadurcopanoplos* gen. nov., with its osteoderms similar to *Sullivanosaurus*, would also represent an example of “intermediate” stage, with a more derived feature: the arrangement of the tubercles into a radiate pattern around the center of the osteoderm. As the phylogenetic topology of Glyptosaurinae needs to be reassessed, it is also possible that *Sullivanosaurus* and *Cadurcopanoplos* gen. nov. represent another glyptosaurine clade than *Placosaurus* and would indicate a greater diversity for Glyptosaurinae in Europe during the Eocene.

## Conclusion

The study of these new and “forgotten” specimens from La Bouffie allowed us to confirm the presence of five taxa previously only mentioned, an indeterminate salaman-drid, cf. *Pelodytes*, an indeterminate gekkotan, aff. *Pseu-dolacerta*, and *Cadurciguana*. We also identified seven new taxon occurrences for La Bouffie, a second inde-terminate gekkotan, two indeterminate species of small lacertids, *Geiseltaliellus* cf. *lamandini*, the new ?pleuro-dontan *Phosphoriguana peritechne* gen. et sp. nov., the new glyptosaurine *Cadurcopanoplos vaylatsensis* gen. et sp. nov., and at least one species of indeterminate anguines. The new glyptosaurine is closer in morphology to early Eocene representatives of this family in Europe, rather to the late Eocene *Placosaurus*. It suggests a higher diversity for the Glyptosaurinae throughout the Eocene in Europe, although phylogenetic analyses are needed to clarify the relationships between the early and late Eocene European glyptosaurines. Through this study and a review of the previously existing literature, we can identify at least 18 taxa of amphibians and reptiles in La Bouffie, making it one of the richest herpetofaunal locali-ties of the late Eocene of Europe.
**Acknowledgements**

We would like to thank Yves Laurent (MHNT) for access to the specimens and Thierry Pélissié (Association des Phosphatières du Quercy) for information regarding the locality of La Bouffie. We also thank Andrej Čerňanský (Comenius University of Bratislava) for useful discussions about lacertids. We finally thank the editor Daniel Marty and the two reviewers, Andrej Čerňanský and Krister Smith, for their insightful and thorough comments and suggestions, which improved the quality of the paper.

**Author contributions**

AL and GLG conceived the study. GLG took pictures of specimens. AL and GLG wrote the main manuscript text. AL prepared Figures. Both authors reviewed the manuscript.

**Funding**

AL acknowledges the Dr. Betsy Nicholls Postdoctoral Fellowship granted by the Royal Tyrrell Cooperating Society (Drumheller, AB, Canada). GLG acknowledges funding from the research project no. 2023/49/B/ST10/02631 financed by the National Science Center of Poland (Narodowe Centrum Nauki).

**Data availability**

No datasets were generated or analysed during the current study.

**Declarations**

**Ethics approval and consent to participate**

Not applicable.

**Competing interests**

The authors declare no competing interests.

Received: 31 January 2025 Accepted: 4 May 2025

Published online: 25 July 2025

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