NECROSAURIDAE, Hoffstetter, 1943
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publication ID |
https://doi.org/ 10.26879/695 |
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persistent identifier |
https://treatment.plazi.org/id/7630AF2B-B322-2C49-FEC9-FC2294D4F8EB |
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treatment provided by |
Felipe |
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scientific name |
NECROSAURIDAE |
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“ NECROSAURIDAE ” Hoffstetter, 1943 “ Necrosauridae ” indet.
Figure 1.19 View FIGURE 1 -20
Material. IPS 83545, fragment of dentary ( Figure 1.19 View FIGURE 1 ); IPS 49741, partial osteoderm ( Figure 1.20 View FIGURE 1 ).
Description. IPS 83545 is a fragment of dentary preserving one incomplete tooth. The tip of the crown is broken, so it is not possible to ascertain if the tooth was originally recurved. The presence of plicidentine is clear at the base of the preserved tooth. IPS 49741 ( Figure 1.20 View FIGURE 1 ) is a partially preserved oval osteoderm with a strong ornamentation formed by pits and ridges, and dorsally presents a high, rather rounded, longitudinal keel.
Remarks. The morphology of IPS 49741 recalls that of osteoderms referred to the genus Necrosaurus from contemporaneous localities from Europe (e.g., Condé-en-Brie; see Augé 2005), although it is also reminiscent of osteoderms of Shinisaurus and Provaranosaurus (see Smith and Gauthier, 2013). However, the osteoderm morphology together with the presence of a fragment of dentary presenting plicidentine and strongly resembling that of Necrosaurus suggests the presence of a “necrosaur” at Masia de l’Hereuet.
Indeterminate lizards (non-ophidian, nonamphisbaenian squamates)
Material. IPS 49742, fragment of left dentary; IPS 49746, anterior portion of a right dentary with two teeth; IPS 59530, vertebra; IPS 59532, tooth; IPS 59539, tooth; IPS 83542, seven fragments of tooth-bearing bones; IPS 83548, four fragments of dentary; IPS 83550, two fragments of tooth-bearing bone; IPS 83541, roughly rounded osteoderm.
Description. This material, including tooth-bearing bones and partial vertebrae, is fragmentary and/or poorly diagnostic, making its referral to a specific lizard family impossible. The osteoderm, IPS 83541, is roughly rounded, partially bevelled, not ornamented, and bearing few foramina and channels on the external surface, and only two foramina on the internal surface.
Remarks. These specimens are listed here because the eventual recovery of additional better-preserved material might make them identifiable in the future. IPS 83541 deserves further attention because apparently it does not belong to any of the forms from the locality bearing osteoderms (glyptosaurs, anguines, “necrosaurs”), and may represent an additional, possibly anguimorphan, unidentified form at Masia de l’Hereuet.
Font del Torricó (Early Eocene, Southern Pyrenean Basin, Àger Sub-basin)
IGUANIA Cuvier, 1817
IGUANIDAE Gray, 1827 Iguanidae indet.
Material. IPS 83531, fragment of tooth bearing bone with two tricuspid teeth.
Description. A poorly preserved fragment of bone preserving two pleurodont, high, and columnar teeth. The crowns bear three cusps, although one of the lateral cusplets is in both cases somewhat worn. No striae are present in the crowns. The subdental shelf barely extends lingually below the tooth bases and, accordingly, there is no sulcus dentalis.
Remarks. The tricuspid condition and overall morphology of the crowns, together with the lack of a sulcus dentalis suggest iguanian affinities for IPS 83531 (not figured). Morphology is close to that of Geiseltaliellus but this specimen is somewhat more robust than other specimens from the Catalan localities. It is not clear, however, if this is related to its slightly larger size (and thus probably related to ontogeny) or, alternatively, to differences at the genus level. The fragmentary nature of this specimen only grants identification of a pleurodont iguanian at Font del Torricó.
ANGUIMORPHA Fürbringer, 1900
ANGUINAE Gray, 1825 Anguinae indet.
Figure 1.16 View FIGURE 1
Material. IPS 83533, body osteoderm ( Figure 1.16 View FIGURE 1 );?IPS 83537, two fragments of vertebrae (condyles).
Description. The only recovered body osteoderm is 2.5 mm long. It is rectangular and bevelled, with the gliding surface occupying one third of its length ( Figure 1.16 View FIGURE 1 ). It presents an ornamentation of pits and ridges typically found in anguines. The external ornamented surface bears a faint keel. The two condyles (IPS 83537) are dorsoventrally depressed and the preserved portion in one of the vertebrae suggests the centrum was narrow and with parallel lateral margins. One of the centra is significantly larger than the other one.
Remarks. The single osteoderm is the best proof of the presence of anguines at Font del Torricó. The ornamentation presented by this element only fits with anguines among the fossil European taxa with which it was compared, although it is slightly different from that of anguine osteoderms from Masia de l’Hereuet and Barranc del Fusteró, suggesting the presence of a second anguine in the early Eocene of Catalonia. Material recovered so far is, however, very limited and precludes a deeper discussion on its affinities. The fragments of vertebrae present some characters of anguine vertebrae, but their fragmentary nature makes a referral to Anguinae much more dubious.
GLYPTOSAURINI Sullivan, 1979 Glyptosaurini indet.
Figure 1.13 View FIGURE 1
Material. IPS 83532, two cranial osteoderms, one fragment of osteoderm ( Figure 1.13 View FIGURE 1 ).
Description. The three osteoderms referred to Glyptosaurinae bear the typical ornamentation of small tubercles. One of the osteoderms ( Figure 1.13 View FIGURE 1 ) is polygonal (?hexagonal), clearly corresponding to the skull, and relatively flat. A second one is more irregular and relatively thick. Its irregular shape and the lack of a gliding surface also suggest that it corresponded to the region of the skull. The third osteoderm bears the same ornamentation as the other two, but it is poorly preserved.
Remarks. The presence of osteoderms with an ornamentation formed of tubercles can only be linked to the presence of Glyptosaurinae , and the presence of clearly polygonal skull osteoderms is typical of the tribe Glyptosaurini . It has to be noted that the figured specimen is slightly more flat than those of the parietal from Escarlà described below and referred to cf. Placosaurus . Skull osteoderms from the late Eocene of Sossís and referred to Glyptosaurini by Bolet and Evans (2013) are much thicker.
Barranc del Fusteró (MP10, Southern Pyrenean Basin, Àger Sub-basin)
ANGUIMORPHA Fürbringer, 1900
ANGUINAE Gray, 1825 Anguinae indet.
Material. IPS 49860, three fragments of osteoderm; IPS 49862, fragment of osteoderm.
Description. The three fragments of osteoderm corresponding to IPS 49860 (not figured) present the typical ornamentation of pits and ridges found in anguines. They are too fragmentary to provide much information on their outline, but one of them suggests it was roughly elliptical. Two of them bear well-developed gliding surfaces. IPS 49862 is more poorly preserved and only tentatively referred to Anguinae on the basis of overall shape and ornamentation (the surface is worn).
Remarks. The fragmentary nature of these specimens precludes any discussion on their affinities, except that their ornamentation is more similar to the anguine specimens from Masia de l’Hereuet than to that from Font del Torricó.
GLYPTOSAURINAE Marsh, 1872 Glyptosaurinae indet.
Material. IPS 49863, body osteoderm.
Description. This small osteoderm (not figured) has the typical tuberculated ornamentation of glyptosaurines. The dorsal surface presents a laterally displaced faint keel.
Remarks. The presence of a keel suggests that this osteoderm corresponded to the body. Accordingly, it cannot be referred to one of the tribes in front of the other, and is thus referred to Glyptosaurinae .
Escarlà (MP10, Southern Pyrenean Basin, Tremp-Grauss Sub-Basin, Pont de Montanyana Area)
ANGUIMORPHA Fürbringer, 1900
Genus PLACOSAURUS Gervais, 1852 cf. Placosaurus
Figure 1.12 View FIGURE 1
Material. IPS 59567 ( Figure 1.12 View FIGURE 1 ), partial parietal.
Description. The single specimen from this locality corresponds to a left half of a parietal table with fused tubercular osteoderms. The latter are polygonal (one of them might have been hexagonal, but preservation precludes a definite statement), relatively flat, and not conical. The tubercles are irregularly arranged on the dorsal surface of the osteoderms. Ventrally, the presence of a medial ridge can be ascertained in the preserved portion of the parietal. The anterior portion of a left lateral ridge is also preserved, but it rapidly reaches the limit of preserved margin of the bone. No parietal foramen is observable because it would have been in the poorly preserved medial margin of the bone. Remarks. The presence of cranial isolated polygonal osteoderms supports a referral to the tribe Glyptosaurini , and not the “ Melanosaurini ” ( Sullivan, 1979). Moreover, the parietal compares well with the contemporaneous parietal referred to? Placosaurus ragei by Sullivan et al. (2012). Sullivan et al. (2012) suggested that the lack of osteoderms in the periphery of the parietal they tentatively referred to? Placosaurus ragei was either a primitive or a juvenile trait. The parietal described here is not well-preserved in its lateral margins, but some osteoderms seem to be lacking even in non-peripherical positions. The fact that failure to fusion occurs also in non-peripherical positions (in contrast to the Dormaal specimen) suggests a certain degree of variability in the degree of fusion of osteoderms to the parietal table. This also occurs in the frontal of Placosaurus estesi , where at least one osteoderm by the side of the midline is missing (see Sullivan and Augé, 2006), and osteoderms close to the anterior, posterior and lateral margins are also lacking. Referral of the specimen from Escarlà to Glyptosaurini is well supported, and referral to Placosaurus seems likely, although it is regarded as tentative.
La Roca (MP10, Southern Pyrenean Basin, Isàbena Sub-Basin)
IGUANIA Cuvier, 1817
IGUANIDAE Gray, 1827 Iguanidae indet.
Material. IPS 9093, A fragment of?dentary.
Description. A fragment of tooth-bearing bone preserving five tricuspid teeth.
Remarks. The tricuspid nature of the preserved teeth as well as resemblance to the genus Geiseltaliellus suggest the presence of this pleurodont iguanian at this locality. However, the fragmentary nature of the specimen does not allow a formal referral to the genus.
La Morera (MP10, Ebro Basin)
IGUANIA Cuvier, 1817
IGUANIDAE Gray, 1827 Iguanidae indet.
Figure 1.3 View FIGURE 1 -4
Material. IPS 83535, fragment of tooth-bearing bone with one preserved and one broken tooth ( Figure 1.3 View FIGURE 1 ); IPS 49756 ( Figure 1.4 View FIGURE 1 ), fragment of maxilla with four teeth; IPS 83522, fragment of tooth-bearing bone with two preserved teeth; IPS 83534, fragment of tooth-bearing bone with one unicuspid tooth and one tricuspid tooth; IPS 49766, fragment of tooth-bearing bone with one preserved tooth.
Description. The small fragment of maxilla IPS 83535 bears one tricuspid tooth. The central cusp is much larger and rounded, the accessory cusps being very small and pointed. The same description is valid for IPS 49756, but this bone is larger, and the tooth tips are worn so that its tricuspidy is less evident.
Remarks. The tricuspidy of these bones point to the presence of a second pleurodont iguanian at La Morera. It differs from Geiseltaliellus by its more robust dentition, teeth that are implanted orthogonal to the dental shelf, a more rounded central cusp, and less marked lateral cusplets. The presence of Geiseltaliellus is, however, not completely discarded at La Morera, as IPS 83534 (not figured) bears teeth that approach the slender dentition of this ubiquitous iguanid genus. However, it is better identified as an indeterminate iguanian at this time, but note that two different forms, one of them close to Geiseltaliellus , might be present at La Morera. It is also acknowledged that the poor preservation of the crowns of IPS 83535 hinders comparison, and it is not discarded that it could represent a different taxon.
GEKKOTA Cuvier, 1817 Gekkota indet.
Figure 1.7 View FIGURE 1 -8
Material. IPS 49754, fragment of right dentary; IPS 59559, posterior portion of left dentary ( Figure 1.7 View FIGURE 1 ); IPS 83520 fragment of left dentary ( Figure 1.8 View FIGURE 1 ); IPS 83521, fragment of right dentary.
Description. These dentaries present a closed Meckelian canal and slender and closely packed teeth. None of the teeth are completely preserved, precluding a description of tooth crowns. It can be stated, however, that teeth were less numerous and crowded than is average for gekkotans. A very deep facet for the splenial is present in IPS 59559.
Remarks. The combination of a completely closed Meckelian canal and closely packed teeth point to the presence of a gekkotan at La Morera. The consistency in size and morphology of the three specimens points to a single form. The recovery of additional material would allow comparisons with the scarce material from Silveirinha (see Rage and Augé, 2003) and, more interestingly, with the Late Eocene material from Sossís, which comprises three different gekkotan forms ( Bolet and Evans, 2013).
“SCINCOMORPHA” Camp, 1923
SCINCOIDEA Oppel, 1811
SCINCIDAE Gray, 1825 ? Scincidae indet.
Figure 1.9 View FIGURE 1
Material. IPS 49752, right dentary fragment with two preserved teeth ( Figure 1.9 View FIGURE 1 ); IPS 49753,?maxilla fragment with two preserved teeth; IPS83527, posterior portion of left dentary.
Description. The teeth of IPS 49752 are wellspaced and posteriorly inclined. They are columnar and present the typical scincoid configuration, with a lingually and a labially positioned cusp (cuspis lingualis and labialis sensu Richter, 1994). Between them there is a sulcus, the antrum intercristatum sensu Kosma (2004). The crowns do not bear striae. The tooth crowns of IPS 49753 are very similar, but instead are rather orthogonal, not posteriorly inclined. The tips of the crowns in IPS 59548 are not well-preserved, but the overall shape of the dentition is similar to that of IPS 49753.
Remarks. The presence of Scincoidea at La Morera is clear after these specimens. Material is too fragmentary to allow more concrete determinations, but the morphology of the crowns is similar to that figured for the scincid Lipinia noctua ( Kosma, 2004, plate VII, figure 1) and would suggest the presence of Scincidae rather than Cordyliformes. The material is clearly different from Scincoideus ( Folie et al., 2005) in that the lingual cusp is large for La Morera specimens, and the separation between teeth is large, against the more close packing of the teeth of Scincoideus . The presence of a well-developed antrum intercristatum is more widespread among scincids, but because it is seldom present in cordyliforms (as well as other scincomorphans; see Kosma, 2004), a formal referral to Scincidae is, despite being the most probable option, not possible at this time.
LACERTIFORMES Estes et al., 1988
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