Camptognathosaurus walbeckensis (Kuhn, 1940a) Čerňanský & Vasilyan, 2024

Cernansky, Andrej & Vasilyan, Davit, 2024, Roots of the European Cenozoic ecosystems: lizards from the Paleocene (~ MP 5) of Walbeck in Germany, Fossil Record 27 (1), pp. 159-186 : 159

Camptognathosaurus walbeckensis (Kuhn, 1940a) comb. nov.

Figs 2 , 3 , 4

Glyptosaurus walbeckensis 1940a (aff.) Glyptosaurus walbeckensis : Kuhn, p. 24, figs 4b, 5b.

Glyptosaurus walbeckensis 1940b " Glyptosaurus " Glyptosaurus walbeckensis : Kuhn, p. 482, tab. II fig. 4, tab. III fig. 3.

Pseudeumeces wahlbeckensis 1983 Pseudeumeces? wahlbeckensis : Estes, p. 104.

Camptognathosaurus parisiensis 2005 Amphisbaenia incertae sedis: Augé, p. 301

Camptognathosaurus parisiensis 2013 Camptognathosaurus parisiensis : Folie, Smith & Smith, p. 229, fig. 3.

Neotype.

MLU.GeoS.4045, almost complete left dentary.

Referred specimens.

Germany (here): Two left maxillae MLU.GeoS.4048-4049; one right maxilla MLU.GeoS.4047; three left dentaries MLU.GeoS.4043-4045, MLU.GeoS.4055, MLU.GeoS.4038, 4039 and 4036; seven right dentaries MLU.GeoS.4051, 4040, 4053, 4037, 4041, 4042, and 4056.

France (see Folie et al. 2013): Two right dentaries RIV PP 413, RIV PP 414; left dentary RIV PP 415, MNHN CR 17420 about fifteen dentaries and maxillae, MNHN CR 17421, right dentary and MNHN CR 17425 left dentary.

Localities and horizons.

The type locality of Camptognathosaurus walbeckensis ( Kuhn 1940a), comb. nov. is Walbeck (~MP 5; Germany). This taxon is also known from France: Rivecourt-Petit Pâtis (MP 6b), Cernay-lès-Reims (MP 6a; both France) and, potentially, Montchenot (MP 6).

Taxonomic comment.

The newly referred dentaries show no evident differences relative to the type material of (aff.) Glyptosaurus walbeckensis described from the same locality ( Kuhn 1940a: figs 4b, 5b): in tooth count, tooth morphology, slightly arched ventral margin of the dentary and prominent, dorsally elevated coronoid process. This species has been considered a glyptosaurid ( Glyptosauridae sensu Čerňanský et al. 2023a) by Kuhn (1940a). This assignment is untenable given the specimens studied here. Aff. Glyptosaurus walbeckensis lacks the following derived characters of Anguioidea ( Estes et al. 1988; Gauthier et al. 2012): the splenial anterior inferior alveolar foramen is located between the splenial and the dentary (usually marked by the splenial spine) and the Meckelian canal opens ventrally in the anterior region (not medially for most of length). Moreover, the sulcus dentalis is present, whereas in anguimorphs, the dental crest is shallow and extends medioventrally. The material of aff. G. walbeckensis was later suggested to belong to Lacertidae (? Pseudeumeces ; see Estes 1983). Augé (2005) suggested that it is a potential amphisbaenian and considered it a nomen dubium. In contrast, the new specimens share the following features of Paleocene Camptognathosaurus parisiensis : a long dentary bearing ten to twelve teeth, absence of an angle at the mandibular symphysis and robust amblyodont teeth decreasing the size towards the anterior end of the bone.

It should be noted that no holotype for aff. Glyptosaurus walbeckensis was explicitly assigned by Kuhn (1940a). He mentioned six dentaries as (aff.) G. walbeckensis , but he figured only one and provided a brief description of the dentary features of this taxon. Accordingly, following ICZN (1999: Article 73.2 and Recommendation 73F), all these six specimens mentioned by Kuhn (1940) (and not only the one he figured) are by definition considered as syntypes of the species. As such, the fact that these specimens cannot be adequately identified because they were not listed, figured, or described in detail does not affect their status as syntypes; in fact, a similar situation has been observed in other fossil Cenozoic reptiles as well, such as the constrictor snake Palaeopython cadurcensis (see Georgalis et al. 2021a: 22) and the testudinid turtle Testudo marmorum (see Vlachos et al. 2020: 3-4). It is difficult to identify the original syntype specimen figured by Kuhn (1940a: fig. 4b, 5b). In the available material studied here, no left dentary seems to be identical to the figured Kuhn’s specimen. Unfortunately, the quality of the figure from the original publication is not sufficient to relocate the specimens. The overall shape and morphology of the figured syntype are very similar to MLU.GeoS.4045 (Fig. 3A-D ), but a more detailed comparison, especially regarding the arrangement of preserved teeth, does not support the assignment. In Kuhn’s (1940a) specimen, there is a small posterior tooth with empty tooth loci anterior to that and five teeth preserved in the row. In MLU.GeoS.4045, six teeth could be counted if we virtually complete the region between the first and last preserved teeth. Another explanation is that the current preservation of Kuhn’s specimen is much worse than in 1940. This would make its identification challenging. In such a case, the specimen MLU.GeoS.4039 (Fig. 4F-H ) with five preserved teeth (and a total of eleven tooth positions) in a complete row would be a good candidate to represent the original Kuhn’s (1940a) figured syntype specimen. In a closer look, however, the anterior portion of this dentary is not identical with the specimen of Kuhn (1940a) - the anterior portion of MLU.GeoS.4039 starts to rise dorsally at the level of the anteriormost preserved tooth (rather that in front of it), the dental crest is preserved in this anterior elevated portion, and the relative mutual size of teeth and their orientation do not match as well. For all these reasons, we cannot confidently exclude an option that the syntype specimen figured by Kuhn (1940a: fig. 4b, 5b) has been lost.

Furthermore, in the same year, Kuhn (1940b) figured two additional specimens that he referred to aff. Glyptosaurus walbeckensis , i.e., a dentary ( Kuhn 1940b:pl. II.4) and a maxilla ( Kuhn 1940b: pl. III.3), which were both figured in much better quality than the figured syntype specimen in his 1940a publication. The same author further briefly described the maxilla ( Kuhn 1940b: 482). However, Kuhn (1940b) did not mention anything that would imply that these two newly figured specimens were part of the original type material of aff. Glyptosaurus walbeckensis that was established in Kuhn (1940a). The fact that Kuhn (1940a) did not mention anything about the existence of a maxilla for this species, renders us to safely regard that the maxilla is not a syntype. As for the dentary, it is impossible to know if this was a newly referred specimen or one of the six syntype dentaries. The same author, in his subsequent compendium of fossil lizards ( Kuhn 1963), also did not specify any type material in the respective entry of this taxon. In the absence of any evidence, we have to treat it similarly to the maxilla, i.e., as a referred specimen. In any case, both these 1940b specimens should also be considered as lost: we have three maxillae in our sample but no one is, again, identical to his 1940b figured one, while the 1940b dentary is similar to the right dentary MLU.GeoS. 4042 described and figured herein (Fig. 4A ), but a detailed comparison shows that this is not the same specimen.

Estes (1983: p.104) regarded the only figured specimen in Kuhn (1940a: fig. 4b, 5b) as the only type specimen. That action of Estes (1983) rendered him, in fact, as the designator of the lectotype, according to ICZN (1999: Article 74.5). By definition, the remaining five, non-figured, dentaries mentioned in Kuhn (1940a) represent paralectotypes of the species. As for two additional specimens figured by Kuhn (1940b), Estes (1983) regarded them as the "referred specimens" and "topotypic specimens".

Taking into consideration the poorly figured lectotype of the aff. Glyptosaurus walbeckensis in Kuhn (1940a), coupled with the apparent loss of this material and the original brief description, we consider that it is most appropriate to designate a neotype that could render the taxon diagnostic and allow its anatomical features to be properly discerned. Camptognathosaurus parisiensis is a junior synonym of the new combination Camptognathosaurus walbeckensis and is a type species of the genus Camptognathosaurus (the type species of a genus can be a junior synonym of a valid species pertaining to the same genus, see ICZN 1999: Article 67.1.2; e.g., the case with the snake genus Eryx Daudin, 1803, but cannot be a non-diagnosable species, which cannot be diagnosed as a member of the genus). One option is to replace the lost one by the holotype of Camptognathosaurus parisiensis (RIV PP 413) in the new combination Camptognathosaurus walbeckensis . However, we think it is less dangerous to choose a neotype among the specimens from Walbeck (the type locality), some of which are not significantly less well-preserved than those from France. The reason for this is that there are more chances that the neotype we are choosing actually belongs to the same species erected by Kuhn, than if we chose it among specimens from a different region (with a slightly different age and which could ultimately be shown to represent a different species). Currently, only jaw elements are known and caution is needed.

Revised diagnosis.

Small-sized lizard in regard to skull length (an anteroposterior maximum length of dentary around 10 mm). It differs from other members of Lacertoidea based on a unique combination of features: (1) pleurodont dentition (contra Trogonophis ); (2) only moderately shortened dentary (as Polyodontobaena , Pseudeumeces , contra distinctly shortened in all modern amphisbaenians, contra markedly short in Dracaenosaurus , contra long in Lacerta and Gallotia ); (3) absence of an angle at the symphysis (as lacertids, Cryptolacerta , contra Cuvieribaena and all modern amphisbaenians except Amphisbaena ridleyi ); (4) rounded (arched) ventral margin of dentary (as lacertids, Cryptolacerta , contra Polyodontobaena and modern amphisbaenians); (5) higher number of labial foramina - around five or six (as Lacerta , Pseudeumeces , contra eight in Gallotia , contra four in Polyodontobaena , three in Blanus and Rhineura , two in Cuvieribaena ); (6) opening of the alveolar canal beneath tooth row (as Cryptolacerta , Polyodontobaena , contra all modern amphisbaenians except Rhineura ); (6) dentary tooth number 10-12 (as Pohl-Perner specimen of Cryptolacerta and Polyodontobaena ; 12-14 in Dracaena , 12-17 in Pseudeumeces , contra higher tooth count in Tupinambis and extant lacertids; contra smaller number - seven or eight in Dracaenosaurus and in all modern amphisbaenians); (7) heterodont dentition, teeth increase their size posteriorly (the last tooth/teeth can be smaller) (as Pseudeumeces , Janosikia , Polyodontobaena , contra decreasing tooth size posteriorly in Cuvieribaena and usually in modern amphisbaenians - note that in Blanus , the third or fourth tooth is smaller); (8) teeth arranged in a single line along the tooth row (contra Dracaena ); (9) robust, blunt teeth with constricted bases present in the posterior half of the tooth row (as Dracaenosaurus , Pseudeumeces , contra presence of robust and blunt teeth without constriction in the anterior region of the tooth row in Cuvieribaena ); (10) absence of cementum deposits (contra teiids); (11) moderately low dental crest, teeth exceed the dental crest by more-or-less the half of the tooth length [as Cryptolacerta , contra high dental crest (most of the ventral tooth length laterally cover by the crest) in Pseudeumeces , Dracaenosaurus , Janosikia and Lacerta , contra low dental crest, shallowly pleurodont (most of the tooth length exposed laterally) in Polyodontobaena and most amphisbaenians]; (12) large, dorsally distinctly elevated coronoid process of dentary, which appears to cover, at least partly, the anterolateral part of the coronoid (as Cryptolacerta and many amphisbaenians, contra basal Rhineuridae ); (13) open Meckelian canal (contra Rhineura ); (14) fossa for adductor musculature well developed, extensive, running well belong the dentary tooth row (as Cryptolacerta ,? Cuvieribaena , contra Polyodontobaena and extant amphisbaenians) and (15) posteroventral process of maxilla long (as lacertids, Cryptolacerta , contra derived state in modern amphisbaenians).

Description.

Maxilla. Three maxillae (two left, one right) are available in the material (Fig. 2A-F ). The specimen MLU.GeoS.4048 is better preserved, whereas 4049 is represented only by a posterior fragment bearing three teeth. MLU.GeoS.4048 possesses six or seven tooth positions (see remarks) with four teeth still attached. The preserved portion of the maxilla appears to be anteroposteriorly short rather than long. Note, however, that it is incomplete and the true length of the element cannot be determined (but see remarks for Kuhn 1940b). It consists of two major portions: the dental portion bearing the marginal dentition and the dorsally extending nasal process (facial process sensu Evans 2008). In dorsal view, the bone gradually widens posteriorly except for the posteroventral process. A short process bearing a facet for the palatine extends posteromedially. Further posteriorly, the bone continues into the posteroventral process. The process is not pointed but forms a low perpendicular wall. The external side of the maxilla is slightly concave. In lateral view, the external surface of the bone is mostly covered by adhering sediment. The partly exposed areas are more-or-less smooth (the same is true for MLU.GeoS.4049 which, however, represents only a ventral portion of the maxilla, see below). The nasal process is small (note that the anterior part of the process is broken off) and slightly dorsally expanded. Its posterior portion is well demarcated from the further posterior portion of the maxilla by a recess.

Further posteriorly, the bone gradually decreases, but note that the dorsal margin of this part is slightly concave. The anterior region of the maxilla is damaged. In medial view, the partly damaged supradental shelf is well-developed and moderately expanded medially. Its maximum medial expansion, corresponding to the palatine process of the maxilla, can be seen at the level of the last posterior preserved tooth. The portion situated further posteriorly appears to be damaged. However, it can be assumed that the process did not protrude distinctly further posteriorly (Fig. 2C ). The large posterior opening of the superior alveolar canal is located in the posterior region at the level of the fifth tooth position (counted from anterior).

The specimen MLU.GeoS.4047 represents a partly preserved right maxilla. It appears to be somewhat long (relative to amphisbaenians), but its dorsal portion, including the nasal process, is completely broken off. The anterior portion is missing as well. The preserved external surface of this specimen is smooth. Only a ventral half of one supralabial foramen is preserved. The bone extends posteriorly into the more-or-less long posteroventral process. The process is slightly inclined laterally relative to the anteriorly located portion of the maxilla (Fig. 2I, J ; the same condition can be seen in MLU.GeoS.4049). The preserved maxilla bears six tooth positions where four teeth are still attached to the bone. The medial margin of the supradental shelf is damaged, although its sharp stepped end around the end of the tooth row is visible. It forms the medially expanded portion. In this area, the facet for the palatine is present. The posterior opening of the superior alveolar canal is located at the level of the penultimate tooth position. The posteroventral process of maxilla is long rather than short. In lateral and medial views (Fig. 2G, H ), its dorsal margin is concave and the posteroventral process forms a low perpendicular wall. The ventral margin of this wall reaches only slightly more posteriorly than its dorsal margin. From the level of the superior alveolar foramen, the posteroventral process is also slightly rotated ventrolaterally. Thus, its lateral surface is partly visible when the maxilla is observed in ventral view (Fig. 2J ). The posterior region of the maxilla appears to bear a facet for jugal (Fig. 2H ).

Remarks. All three maxillae, despite some small differences, are allocated to the same species. They share several features, such as robust teeth of which a robustness increases posteriorly; the location of the palatine process; and the presence of well-developed posteroventral process (in contrast to modern amphisbaenians). Identical dentition in this type of element helps to recognize that they most likely belong to the same taxon as dentaries described below. Moreover, they are comparable in size and come from the same locality. It seems to be unlikely that maxillae belong to a form for which dentaries have not been recorded in the locality. The small differences among maxillae are considered individual variability and/or may reflect ontogenetic differences (see Discussion). Therefore, until the intraspecies variability and ontogeny is better understood in this form, we prefer to provisionally refer the new maxillae to the species Camptognathosaurus walbeckensis comb. nov.

The tooth number in the tooth row is difficult to estimate because the region of the last posterior tooth in MLU.GeoS.4048 is damaged. It seems that there could be a place for one additional tooth. But in such case, this tooth, if present, would be much smaller than the last preserved (potentially penultimate) tooth. Actually, this would not be unusual and cannot be excluded (although nothing indicates such a condition in MLU.GeoS.4049). In such a case, the maxillary tooth number in a preserved (not complete) tooth row of this specimen is seven.

Besides these three specimens, there is an additional right maxilla figured by Kuhn (1940b: tab II fig. 4). This Kuhnʼs specimen is much more complete, but is not present in the material available to us (according to Estes 1983, it is lost). There are similarities with our material, such as an amblyodont dentition and a long posteroventral process with a concave dorsal margin, although it is difficult to be absolutely sure without proper study that this specimen represents the same taxon ( Camptognathosaurus ). Only its lateral aspect is figured and according to Kuhn (1940b), it has 11 mm in length (it is moderately long rather than short) and possesses seven teeth (the tooth count of a complete tooth row was ten). Its external surface (including the nasal process) is pierced by numerous small foramina. The posteriormost supralabial foramen is located at the level of the fourth tooth position. The nasal process is anteroposteriorly long but dorsally low. Its dorsal margin is rounded, whereas its posterior portion slightly protrudes posteriorly. This portion is triangular, pointed and posteriorly directed. Estes (1983) stated that there is a weak sculpture reflecting osteodermal attachment on the nasal process.

Dentary. Several dentaries are preserved. Most of them are, however, only fragmentary (Figs 3 , 4 ). The complete tooth row is preserved in the dentaries MLU.GeoS. 4045 (neotype) and 4051 (Fig. 3A-G ). The specimens bear twelve tooth positions (two teeth are still attached to the bone in 4051, see Fig. 3E, F ; whereas four are preserved in 4045, see Fig. 3A-C ). Some smaller dentaries bear eleven or perhaps ten tooth positions - this estimation is based on MLU.GeoS.4038, where only the anteriormost portion is broken off, but nine tooth positions are preserved (seven more-or-less complete teeth and half of two anteriormost ones are preserved in this specimen).

The otherwise smooth lateral surface is pierced by a single row of five (in MLU.GeoS.4051) to six (in 4045) labial foramina (in some cases four, e.g., MLU.GeoS. 4042 - note, however, that these specimens are incomplete; Fig. 4A ). The foramina are located in the mid-line of the bone and gradually increase in size posteriorly. The posteriormost foramen is located at the level of the fifth tooth position (counted from posterior) in MLU.GeoS.4051, but at the third in 4045 (note, however, that this is not a result of a different placement for the foramen in the dentary, but of the closely packed posteriormost teeth in 4051). In the posterior region of the dentary, there is a well-developed, wedge-shaped fossa for the adductor musculature. This structure is extensive, running well below the tooth row.

In medial view, the Meckelian canal is fully open, although narrow in the anterior region - the canal gradually widens posteriorly. The intramandibular septum, which separates the Meckelian canal from the alveolar canal, extends posteriorly almost to the end of the tooth row, but does not surpass it. The septum reaches the level of the third tooth position (counted from posterior) in MLU.GeoS.4051, whereas it reaches the level of the last tooth position in 4045 (this is likely related to the two additional posterior teeth in 4051, not a true shift in the structure position). The ventral margin of the septum forms a small and narrow crest (Fig. 3B ). This crest is not free but is ventrolaterally fused to the bone (thus, this is not identical to a free posteroventral margin of the intramandibular septum sensu Gauthier 1982). Dorsally, the opening of the alveolar canal (i.e., alveolar foramen) is located. A subdental shelf roofs the Meckelian canal. Dorsally, the subdental shelf bears the sulcus dentalis (the sulcus becomes shallower posteriorly). The shelf is robust in the anterior section (Fig. 3B ), but it distinctly narrows posteriorly due to the presence of the facets for the splenial and large facet for the coronoid on its ventromedial surface. The splenial facet is medially exposed and visible at the level of the third tooth position (counted from posterior; this condition is present in all specimens in which this feature can be observed). Then, it turns more ventrally and reaches far anteriorly, extending to the level of the sixth tooth position counted from posterior or the seventh tooth position if counted from anterior. The symphyseal region is preserved in MLU.GeoS.4045. It is slightly dorsally elevated relative to the mid-section of the shelf (the subdental shelf is slightly dorsally concave). The symphysis is small and rectangular in shape. The facet for the splenial is also present on the ventral margin, but the margin itself is weathered, worn or corroded in the specimens so it is difficult to estimate its anterior termination. The ventral margin of the bone is slightly arched. The posterior region of the bone (posterior to the end of the tooth row) distinctly rises dorsally to form a dorsally elevated and prominent coronoid process. It appears that it covered, at least partly, the anterolateral part of the coronoid. The coronoid itself is not preserved, so this cannot be fully confirmed. The coronoid process of the dentary is fairly preserved in MLU.GeoS.4045. Only its dorsal portion is slightly damaged. The process reaches clearly higher than the level of the tooth apices of the largest teeth. The ventral posterior ends of all dentaries are damaged. At least a short angular process can be identified in MLU.GeoS.4045 (Fig. 3A, B ). However, this appears to be only the base of the process, so its real length is unclear. The same is true for MLU.GeoS.4036, a left dentary without teeth.

Dentition. The tooth implantation is pleurodont. Teeth are tall (relative to the overall size of the jaw), overarching the moderately low dental crest by more-or-less the half of the tooth length. Tooth size (robustness) in both maxilla and dentary gradually increases posteriorly. Note, however, that the last and/or penultimate tooth can be somewhat smaller again relative to the next anteriorly located tooth. The teeth are straight (not recurved) and slightly inclined anteriorly. In general, they are robust with blunt apices. The large teeth in the posterior region are extremely blunt, amblyodont and have rounded apical portions forming robust cylinders. Some specimens bear well-preserved fine radial striations of the crowns (Fig. 3M, O ). The teeth are slightly constricted at their bases. Here, large circular resorption pits are located.

Although teeth are robust in some specimens, they have a slightly pointed appearance rather than being rounded and distinctly blunt. In some of these specimens, tooth crowns (however not all of them) have rounded mesial and slightly concave distal margins (Fig. 4H ; note that this is also present in the penultimate preserved tooth of MLU.GeoS.4045, although in lesser form; see Fig. 3D ). This feature (weak pointedness), however, can somehow vary among individuals and even in a single tooth row. Moreover, the conditions in the MLU.GeoS.4047 maxilla and 4042 dentary rather reflect an intermediate stage (Figs 2H , 4B ; see remarks and Discussion).

Remarks.

The material described here shares morphological features with the material of Camptognathosaurus parisiensis described by Folie et al. (2013: fig. 3) from France (MP 6b, Rivecourt-Petit Pâtis; MP 6a, Cernay-lès-Reims). The dentary RIV PP 413 (the holotype in Folie et al. 2013) is markedly similar to the specimen MLU.GeoS.4045 we describe here (Fig. 3A-D ). All specimens from Germany and France (all localities are geographically relatively close to each other, see Fig. 1 ) share the following combination of features: (1) slightly rounded (arched) ventral margin of dentary; (2) number of labial foramina; (3) position of the alveolar foramen; (4) heterodont dentition in regard to size; (5) robust, blunt teeth with slightly constricted bases present in the posterior half of the tooth row (the last tooth/teeth can be smaller); (6) large, dorsally distinctly elevated coronoid process; and (7) similar tooth number - the specimen RIV PP 413, which is represented by a nearly complete right dentary from Rivecourt-Petit Pâtis, bears eleven tooth positions. Both paratypes CR 17420 and CR 17425 are, however, incomplete.

It should be noted that some dentaries described here show several small differences (or variation) among them: (1) size; (2) blunt tooth crown vs. slightly more pointed (although still robust); (3) slightly lower tooth number (twelve vs. eleven or? ten tooth positions); and (4) potentially also the shape of the coronoid process. If the coronoid process is robust, dorsally rising in those dentaries with the well-preserved posterior portion (Fig. 3 ), the shape of this process is difficult to demonstrate clearly in some other dentaries. Namely, it is not markedly dorsally elevated in MLU.GeoS.4042 (Fig. 4A, B ) and 4038 (Fig. 4C, D ). It is clearly unrelated to the early ontogeny because the dorsally distinctly protruding process is observed in a small specimen MLU.GeoS.4041 (Fig. 4K, L ). However, the left dentary MLU.GeoS.4038 is eroded. The relatively lower process in these two mentioned specimens seems to reflect only an artefact of preservation. All other differences seem to fall into the normal individual (and/or ontogenetic) variation; thus, all specimens studied here represent most likely a single taxon (see Discussion).

Figures

Figure 1. Location of Walbeck in Germany and other Paleocene localities of Northern France that yielded Camptognathosaurus.

Figure 2. Camptognathosaurus walbeckensis comb. nov. from the Paleocene Walbeck locality. Two left maxillae MLU. GeoS. 4048 (A - D) and MLU. GeoS. 4049 (E, F) and right maxilla MLU. GeoS. 4047 (G - J) in lateral (A, E, G); medial (B, E, H); dorsal (C, I); and ventral (D, J) views.

Figure 3. Camptognathosaurus walbeckensis comb. nov. from the Paleocene Walbeck locality. The neotypic left dentary MLU. GeoS. 4045 in lateral (A), medial (B), dorsal (C) views; and tooth detail in medial (D) view. Right dentary MLU. GeoS. 4051 in lateral (E) and medial (F) views; and detail of the area around the alveolar foramen in ventromedial (G) view. Left dentary MLU. GeoS. 4055 in lateral (H), medial (I) and dorsal (J) views. Right dentary MLU. GeoS. 4037 in lateral (K) and medial (L) views; and teeth in dorsal (M) view. Left dentary MLU. GeoS. 4043 in lateral (N) and medial (O) views; and detail of teeth in medial (P) view.

Figure 4. Camptognathosaurus walbeckensis comb. nov. from the Paleocene Walbeck locality. Right dentary MLU. GeoS. 4042 in lateral (A) and medial (B) views. Left dentary MLU. GeoS. 4038 in lateral (C), medial (D) and dorsal (E) views. Left dentary MLU. GeoS. 4039 in lateral (F), dorsal (G) and medial (H) views and with detail of teeth (H 1). Right dentary MLU. GeoS. 4056 in lateral (I) and medial (J) views. Right dentary MLU. GeoS. 4041 in lateral (K), medial (L), and dorsal (M) views.