Introduction

Girdled lizards (Cordylidae) are poorly represented in the European fossil record, but they arouse the interest of scholars for their palaeobiogeographic and palaeoenvironmental significance (e.g., Augé 2005; Čerňanský 2012; Jost et al. 2015; Georgalis et al. 2019). Up to very recent times, at least two different cordylid lineages were reported from the Cenozoic of Europe, namely the lineages of ‘Bavaricordylus’ and Palaeocordylus (e.g., Roček 1984; Čerňanský 2012, 2016; Georgalis et al. 2017, 2019; Villa and Delfino 2019a). Nevertheless, Villa et al. (2018) demonstrated that remains attributed to the two species included in the lineage of ‘Bavaricordylus’, actually pertained to a lacertid. They referred the material to Janosikia Čerňanský et al. (2016a, b), also considering that the name ‘Bavaricordylus’ was erected in an unpublished PhD thesis (Kosma 2004) and was, therefore, not valid after the rules of the International Code of Zoological Nomenclature (see comments about this in Villa et al. 2018). However, they also acknowledge the presence of another occurrence of ‘Bavaricordylus’, unidentified to species, reported from the level 642 of Schmiedrued-Pfyffrüti (early middle Miocene, ca. 15.7–15.8 Ma, of Switzerland) by Jost et al. (2015). At the time, a clear evaluation of the affinities of the Swiss material was not possible and so Villa et al. (2018) left it open whether it also pertained to the lacertid Janosikia or if it really represented a cordylid. This question can be finally addressed now, and we here present a reevaluation of the Swiss ‘Bavaricordylus’, with new figures and for the first time a detailed description of remains referred to it.

Material and methods

The original identification of ‘Bavaricordylus’ sp. from Schmiedrued-Pfyffrüti by Jost et al. (2015) was based on four fossil remains: one dentary and three isolated teeth (Davit Vasilyan, pers. comm. to A.V.). Of these, only the dentary and one of the teeth were stored in the collections of the Staatliche Naturwissenschaftliche Sammlungen Bayerns-Bayerische Staatssammlung für Paläontologie und Geologie (SNSB-BSPG) in Munich and available to us for this study. Terminology in the descriptions follows Villa and Delfino (2019b) for the main structures of the dentary, and Villa et al. (2018) for tooth structures. Pictures were taken with a Leica M165 FC microscope, equipped with a DFC450 camera and the Leica Application Suite 4.5.

Institutional abbreviations. SNSB-BSPG—Staatliche Naturwissenschaftliche Sammlungen Bayerns-Bayerische Staatssammlung für Paläontologie und Geologie, Munich, Germany.

Systematic palaeontology

Order Squamata Oppel, 1811

Family Lacertidae Batsch, 1788

Subfamily Gallotiinae Cano, Baez, López-Jurado, and Ortega, 1984


Genus Janosikia Čerňanský, Klembara, and Smith, 2016


Type species. Janosikia ulmensis (Gerhardt, 1903), from the Lower Freshwater Molasse, early Miocene (middle Agenian, MN 2a) sediments north–west of Ulm, Germany.


Janosikia sp.

Figures 1, 2

Fig. 1
figure 1

Left dentary (SNSB-BSPG 2015 XXXIII 1) of Janosikia sp. from Schmiedrued-Pfyffrüti: a medial view; b lateral view; c detail of posterior teeth in medial view; d detail of anterior teeth in medial view; e detail of anterior teeth in lateral view; f detail of posterior teeth in lateral view. Large white arrows point at the accessory cusp on second to last posterior tooth, whereas small ones indicate areas where the wearing is more visible at the teeth tip. ms mandibular symphysis, saf anterior end of the splenial articular facet. Scale bars equal 1 mm (a and b) and 0.5 mm (c–f)

Full size image
Fig. 2
figure 2

Isolated posterior tooth (SNSB-BSPG 2015 XXXIII 2) of Janosikia sp. from Schmiedrued-Pfyffrüti: a occlusal view; b interpretative drawing; c lingual view; d interpretative drawing. Scale bar equals 0.5 mm

Full size image

Studied material. One left dentary (SNSB-BSPG 2015 XXXIII 1) and one isolated tooth (SNSB-BSPG 2015 XXXIII 2).


Description. The fragmentary dentary (Fig. 1) is 7.5 mm long and moderately robust. It represents the anterior portion, missing only the most anterior tip. The ventral margin is convex. In medial view (Fig. 1a), it displays a very wide Meckelian groove, which strongly expands posteriorly and opens in medial direction. Dorsal to the fossa, there is a very high subdental table, with a flat medial surface. In dorsal view, the table is poorly developed in a medial direction. A low but sharp subdental ridge is present, marking medially a very shallow sulcus dentalis. At the anterior end, there is a wide mandibular symphysis, which is, however, mostly missing due to the anterior breakage of the bone. A splenial articular facet is visible on the ventral margin of the subdental table, almost reaching the mandibular symphysis (only the anteroposterior length of a single tooth separates them). The lateral surface of the bone is rough (Fig. 1b). Five, more or less anteroposteriorly aligned mental foramina are present. These are not enlarged compared with the overall size of the dentary, as it is the case in juvenile lizards (Evans 2008).

The preserved portion of the tooth row possesses 10 teeth, plus an empty space for an 11th one right in the middle. The teeth are cylindrical, pleurodont, and closely spaced. The interdental spaces are less than one-third of the anteroposterior length of the teeth. The teeth are rather narrow, with a very slight trend towards an increasing robustness posteriorly. The tooth shaft shows a light swelling close to the tooth base. The tooth crowns are rather blunt. Teeth closer to the anterior end of the dentary (Fig. 1d, e) show a more tapering (pointed) tip, at least in the best-preserved ones. The tip is posteromedially oriented in all teeth, but this is slightly less evident in the posteriormost ones. At least some teeth in the posterior section (Fig. 1c, f) of the preserved tooth row display an anterior accessory cusp, in addition to the main one. This cusp is particularly evident and well developed in the second to last tooth. A very strong and dense striation is present on the lingual side of the tooth crowns, whereas striae are lighter (but still dense) on the labial side; development of the labial striation clearly increases from anterior to posterior teeth. The cristae mesialis and distalis are well developed and sharp, when not obliterated by a low degree of wear interesting the tip of some of the teeth (Fig. 1c, d). On the other hand, the striae dominantes are not clearly visible, likely because the portion of the teeth, where they should be more evident, is eroded away; as a matter of fact, just their bases are somehow visible and only in the best-preserved anteriormost teeth. In any case, it is clear from these that the antrum intercristatum was wide. In labial view, the crowns are the only portion of the teeth that is visible.

The isolated tooth (Fig. 2) is represented only by the crown, which is 1 mm in mesiodistal length and slightly less than 1 mm in labiolingual width. The crown is blunt and rather wide, indicating a rather robust tooth originally (and so likely from the posterior portion of the tooth row). The rounded occlusal surface of the crown is crossed mesiodistally by a sharp carina (Fig. 2a, b), originated by the merging cristae mesialis and distalis (this carina may have been present in the largest teeth of the dentary SNSB-BSPG 2015 XXXIII 1 as well, but if so, it is likely obliterated by the wearing). In occlusal view, the carina has a sigmoid course, due to the slight posteromedial displacement of the tip of the tooth. In labial and lingual views, a very distinct accessory cusp is clearly visible anteriorly (Fig. 2c, d). A strong and dense striation is present both lingually and labially.


Remarks. The Swiss material shares similar morphology and size with the remains of Janosikia sp. from Puttenhausen 2 (‘Bavaricordylus’ molassicus in Böhme 2010). Thus, it can also be referred to Janosikia. In particular, according to Čerňanský et al. (2016b) and Villa et al. (2018) this attribution is supported by: general morphology of the dentition, tall subdental table, wide Meckelian groove, convex ventral margin, and overall robustness of dentary. The rough lateral surface of the dentary is shared by the Swiss Janosikia and the Petersbuch and Puttenhausen occurrences, but not with the type species of Janosikia, described from Ulm-Westtangente. The labial striation is light in the teeth of the dentary SNSB-BSPG 2015 XXXIII 1 and in Janosikia from Puttenhausen (Böhme 2010; Villa et al. 2018), but stronger in Janosikia from Petersbuch (Kosma 2004; Villa et al. 2018), Ulm-Westtangente (Čerňanský et al. 2016b), and on the tooth SNSB-BSPG 2015 XXXIII 2. Based on a comparison with the dentary from Puttenhausen, it can be estimated that only two teeth are missing from the anterior end of SNSB-BSPG 2015 XXXIII 1. If this is correct, the splenial articular facet would end between the fifth and the sixth tooth in the Swiss specimen, which is slightly more anteriorly than in the German dentary and even more so than in the type species Janosikia ulmensis. Another difference showed by the Swiss Janosikia seems to lay in the distinct accessory cusps present in at least some of the teeth. These are indeed reported by Čerňanský et al. (2016b) for J. ulmensis, but only for juvenile specimens and in some maxillary teeth. The size of the Swiss material, however, is comparable with adults rather than juveniles. Taking all of this into consideration, the Swiss Janosikia seems to show the closest morphological affinity with the Puttenhausen taxon, even though some differences are present between them, i.e., presence of an accessory cusp on the posterior teeth, location of the anterior ending of the splenial articulation, and, only in the isolated tooth, development of the labial striation. It is not clear whether these morphological differences might be interpreted as individual variation or if they reflect taxonomic difference at the species level. Nevertheless, the presence of different degrees of development of the labial striation in teeth from the same locality may suggest that this feature is somehow variable in Janosikia. The alternative explanation of two different species coexisting in Schmiedrued-Pfyffrüti is, of course, possible, but basing this on a single feature of uncertain taxonomic significance is here considered less probable.

Discussion and conclusions

Fossils formerly attributed to ‘Bavaricordylus’ from the early middle Miocene of Schmiedrued-Pfyffrüti are herein showed to pertain to Janosikia instead, representing, therefore, the first occurrence of this lacertid lizard outside of Germany. Morphological comparisons of the different remains attributed to the genus seem to highlight the presence of at least two morphotypes. The first one, mainly characterized by a smooth lateral surface of the dentary, is represented by the type species Janosikia ulmensis, whereas the second one, with a rough lateral surface of the dentary, is present in all younger sites in Germany and Switzerland. Possible recognition of this second morphotype as a distinct Janosikia species would need additional material, ideally including further cranial and postcranial elements. Known specimens ascribable to it coming from different localities show a certain degree of variation mainly in tooth morphology and other, maybe minor, features of the dentary, but whether this may sustain the recognition of different taxonomic entities within the group cannot be clarified at the moment. In any case, and given the current absence of any trace of Janosikia remains from other fossiliferous localities outside of Germany and Switzerland, it can be hypothesized that this lacertid genus was confined to this part of Central Europe, where it thrived at least during the early and middle Miocene. According to Čerňanský et al. (2016b), the closest relatives to J. ulmensis are lizards of the genus Gallotia (supported also by Čerňanský et al. 2017, Cruzado-Caballero et al. 2019, and Garcia-Porta et al. 2019, but see Tschopp et al. 2018, for a different possible interpretation), which inhabit the Canary Islands. Sister to the clade composed by these lizards is the French Paleogene species Pseudeumeces cadurcensis, which was tentatively identified also from the late Oligocene of southern Germany by Čerňanský and Augé (2012) and Čerňanský et al. (2016a). In this context, and following also Čerňanský et al. (2016b), we can further hypothesize that an ancestral stock of gallotiine lizards might have been widespread in Central and Western Europe. This gave rise first to Pseudeumeces and then to a lineage that further split to originate Janosikia in Central Europe and the ancestor of Gallotia, which finally reached the Canary Islands through a route that still has to be clarified.

Reassignment of the herein-studied remains to a lacertid leads to slightly revise the inferred palaeoenvironment of level 642 at Schmiedrued-Pfyffrüti. Based on the supposed presence of the thermophilic cordylids, Jost et al. (2015) estimated a mean annual temperature ≥ 17 °C. Such a precise estimate has to be rejected now, in the light of the new identification of the ‘Bavaricordylus’ fossils. Despite this, a warm palaeoclimate for level 642 is still supported by the recovery of other thermophilic taxa such as e.g., the snakehead fish Channa and the crocodylians (Jost et al. 2015; Mannion et al. 2015). The occurrence of Janosikia in Schmiedrued-Pfyffrüti together with abundant molluscs (even though mostly freshwater taxa) and no Pseudopus agrees with the possible competitive exclusion between this amblyodont lacertid and the latter anguid taxon proposed by Klembara et al. (2019). However, Janosikia co-occurs with Pseudopus in Petersbuch 2 (Klembara et al. 2010) and Sandelzhausen (Böhme 2010), thus hinting that a more complex evolutionary pattern (or just mixing of elements of different communities at those sites) may be involved.