Europejara
Genus of tapejarid pterosaur
From Wikipedia, the free encyclopedia
Europejara is a genus of tapejarid pterosaur from the Early Cretaceous (Barremian) of Spain. The type and only species known is Europejara olcadesorum.
| Europejara Temporal range: | |
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| Slab and counterslab of the holotype skull; A shows the main slab under ultraviolet light, B shows the acid-prepared counterslab | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | †Pterosauria |
| Suborder: | †Pterodactyloidea |
| Clade: | †Azhdarchoidea |
| Family: | †Tapejaridae |
| Subfamily: | †Tapejarinae |
| Tribe: | †Tapejarini |
| Genus: | †Europejara Vullo et al., 2012 |
| Species: | †E. olcadesorum |
| Binomial name | |
| †Europejara olcadesorum Vullo et al., 2012 | |
Discovery and naming
The Castilla-La Mancha region of eastern Spain contains many rich fossil localities spanning from the Precambrian to the Pleistocene, and the Las Hoyas site of Serranía de Cuenca in the Southwestern Iberian Ranges has been particularly noted for its exceptional konservat-Lagerstätte preservation. The locality belongs to the La Huérguina limestone Formation and dates to the Upper Barremian of the Early Cretaceous. The site was discovered in 1985, and since then, nearly 30 excavation campaigns have yielded over 19,000 fossils, housed at the Sciences Museum of Castilla-La Mancha in Cuenca. The completeness of the site's fossil flora and fauna has given it worldwide scientific renown, and it was declared a Site of Cultural Interest in 2016.[1][2]
In 2012, the palaeontologist Romain Vullo and colleagues reported an incomplete skull of a new pterosaur from Las Hoyas, the first member of the family Tapejaridae known from Europe, adding to the poorly known pterosaur fauna of the locality. At the time, it was also the oldest known tapejarid and oldest known toothless pterosaur. The specimen (deignated as MCCM-LH 9413 in the Sciences Museum) was made the holotype of the new genus and species Europejara olcadesorum. The generic name combines the names of Europe (itself derived from Europa, a Phoenician princess of Greek mythology) where it was found, and the related genus Tapejara, the Brazilian genus that defines the clade Tapejarinae. The name Tapejara itself is composed of the Tupí-Guaraní words "Tapi" or "Tape", which means path, and "Yara" or "Jara", which means lord. The specific name refers to the Olcades, an ancient Celtiberian people from Hispania that first inhabited the region of Cuenca.[2][3]
The holotype consists of the hind part of a skull with lower jaws, compressed on a slab and counterslab. Several scleral ring bones (that formed a bony ring inside the eye) and two elements of the hyoid (tongue bone) are also present. The skull is crushed and flattened from top to bottom, with various bones displaced, and the mandible is almost complete. No integument, such as soft tissue and keratinous parts, is preserved. The preparation of the specimen included removing elements from the fossil matrix with acid and it was photographed under ultraviolet light for its description. The fossil was presented at an "open doors" event in 2012, which included the best Las Hoyas fossils of the Sciences Museum, where the audience interacted with the researchers who showed study techniques.[2]
Description
Europejara was a relatively small tapejarid, with an estimated wingspan of 2 m (6.6 ft). What is preserved of the holotype skull is incomplete and is flattened dorsoventrally (from top-to-bottom), whereas the mandible is preserved in a lateral (side) view. Due to the crushing of the skull, its fragments, mainly representing elements from the area around the right eye socket, show little detail. Both maxillae are preserved, though are fragmentary. The part of the left jugal bone which connected to the postorbital (the bone behind the orbit, or eye socket) and was found anterior to the quadrate bone, is known; the right jugal, if present, was too fragmentary to be identified with any level of confidence. The postorbital was roughly triangular. A lacrimal bone was tentatively identified by the authors, which, if that identification is correct, is typical in morphology among tapejarines.[2]
Like other tapejarids, Europejara's dentaries (the bones at the front of the lower jaw) supported a large crest, four times deeper than the back of the lower jaw in its case. The crest pointed downward for at least 9 cm (3.5 in), making it the longest dentary crest relative to lower jaw length of any known pterosaur. While enough is preserved to determine that the posterior (rear) portion of the jaw was backswept, the tip and anterior (front) surface are not preserved, so its full shape cannot be established. The hyoid apparatus, a structure involved in supporting the tongue and larynx, is preserved in the form of the first pair of ceratobranchial bones. Each is about 13.5 cm (5.3 in) in length and 0.2 cm (0.079 in) in diameter.[2]
Both the premaxillary and mandibular crests are low in Sinopterus and Huaxiadraco, while they are well-developed in Tapejara and Tupandactylus, indicating that their dimensions can be roughly correlated in tapejarids. Vullo and colleagues therefore inferred that the deep dentary crest of Europejara suggested that its sagittal crest was relatively high, and may have been backwards recurved, mimicking the shape of the dentary crest.[2]
Classification
Europejara was assigned to the Tapejaridae by Vullo and colleagues in their 2012 description. A cladistic analysis showed it to be more precisely a member of the Tapejarinae. Apart from being the first tapejarid known from Europe, it would also be the oldest pterosaur with certainty known to be toothless; older fragments have been reported representing other generally toothless clades but these did not include the jaws themselves.[2]
The cladogram below follows a phylogenetic analysis by Kellner, one of the describers of Europejara, and colleagues in 2019. They recovered Europejara within the tribe Tapejarini, sister taxon to three other genera: Caiuajara, Tapejara, and Tupandactylus.[4]
| Azhdarchoidea |
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Palaeobiology
Vullo and colleagues pointed found the shape of Europejara's mandibular crest unique, unlike any before described among pterosaurs. The purpose of such a deep and recurved crest at the midline of the mandible remains unclear, but there may have been multiple functions, such as use in aerodynamics, thermoregulation, social behavior, or to support a gular pouch. Well-developed bony cranial crests are known from various pterosaur groups, but mandibular crests are only known from anhanguerids and tapejarids, as well as some early non-pterodactyloids.[2]
Diet
Vullo and colleagues pointed out in 2012 that Europejara was the oldest known certainly toothless pterosaur, which might have been linked to the group developing new feeding strategies during the Early Cretaceous; toothlessness probably evolved independently at least three times among pterosaurs. These authors noted that tapejarids are thought to have been good fliers with excellent vision, and have mainly been considered frugivorous (fruit-eaters) and/or granivorous (seed-eaters), based on the shape of their toothless jaws. The beak was probably covered by a rhamphotheca (a keratinous covering), and while shaped like the underlying bone as in modern birds, the bills of some tapejarines might have had pointed projections as in omnivorous birds such as toucans. This indicates tapejarines could also have had a herbivorous or omnivorous diet that included seeds, fruits, insects, and small vertebrates.[2]
The Cretaceous Terrestrial Revolution is a turn-over event in the ecosystems of the Cretaceous in which gymnosperms were replaced by angiosperms, flowering plants, associated with the diversification of insects, birds and mammals. Vullo and colleagues noted that the role of pterosaurs had not been previously considered in this event, but pointed out that an effective mode of seed dispersal by vertebrate animals would have aided the rapid, worldwide spread of angiosperms. The Early Cretaceous La Huérguina Formation in Spain and the Yixian and Jiufotang formations in China preserve fossils of organisms that may have lived in subtropical wet, forested and lacustrine environments that contained an abundance of early angiosperms, and these authors found this to support the presence of frugivorous and granivorous pterosaurs that would have dispersed seeds with birds and insects.[2]
Tapejarines were part of these trophic networks during the Cretaceous Terrestrial Revolution and their distinct features may have been connected to angiosperm dispersal; tapejarines and early angiosperms radiated synchronously and had a similar patchy distribution in time and space. Vullo and colleagues therefore suggested that the Barremian–Aptian distribution of tapejarines partially coincided with the first phase of angiosperm radiation in both the world's hemispheres. Angiosperm diversification during that time is well-documented from Iberian fossils and the Aptian–Albian Crato and Santana formations of Brazil also have early angiosperm assemblages and tapejarines. The describers considered this evidence for congruence between the early radiation of angiosperms and tapejarines, and that these pterosaurs were one of the biological vectors involved in dispersing the flowers between landmasses, but cautioned that more research was required to establish whether the two groups co-evolved or if tapejarines were incidental vectors, with more fossils and gut-content needed for confirmation.[2]
In 2025, the palaeontologist Shunxing Jiang and colleagues reported stomach contents from the abdominal cavity of a specimen of the Chinese tapejarid Sinopterus. These include gastroliths (stones used to aid food processing in the gizzard) and the first evidence of phytoliths in pterosaurs (minerals found in certain plants which persist after their decomposition), and the first evidence of these co-occuring in a pterosaur. Earlier known pterosaur stomach contents are all from more basal pterosaurs, containing fish remains. The gizzard of the Sinopterus specimen is similar to that of the bird Jeholornis, and the pattern and size of their gastroliths are similar; since both belonged to the Jehol Biota, these writers suggested they shared a herbivorous diet such as seeds and grains. Some of the phytoliths of the specimen were identified as the angiosperm family Poaceae as well as gymnosperms or ferns, indicating Sinopterus had a diverse diet of plants. While noting that tapejarids and some other pteosaurs had earlier been suggested as herbivorous based on indirect evidence, these researchers considered the gut contents confirmation of herbivory, and excluded a generalist diet for Sinopterus since for example no undigested bones, scales, or insect exoskeletons were found. They also stated that bite force estimations of the related Tapejara had suggested a herbivorous diet of fruits, seeds, and more resistant plant matter, and added that the similarity between their skulls indicated similar bite forces, supporting a herbivorous diet for both.[5]
Palaeoenvironment
The Las Hoyas Konservat-Lagerstätte, from which Europejara's holotype was recovered, has been dated to the late Barremian (129.4–126.3 Ma) based on charophyte and ostracod assemblages,[6] and was likely deposited in a subtropical wetland environment,[7] between a lacustrine (lake) environment and a tree fern-dominated savannah. Preservation at the Las Hoyas site is so precise that certain taxa, such as Spinolestes, have been preserved with their internal organs intact, and even bacteria have been described. More than twenty thousand plant and animal fossils are known from Las Hoyas. The biota of Las Hoyas is intermediate between Jurassic and other Early Cretaceous biotas, and is thus representative of the early stages of the Cretaceous Terrestrial Revolution.[6] Plants known from the site include the ferns Cladophlebis and Weichselia. Angiosperms, or flowering plants, were another component of the Las Hoyas flora: the oldest angiosperm macrofossil, the aquatic Montsechia, comes from this site.[8]
Pterosaurs are rare in Las Hoyas; in adittion to Europejara, a few teeth indicate the presence of a large anhanguerid and a small istiodactylid.[2] Nonavian theropods are represented by the carcharodontosaurid Concavenator and the ornithomimosaur Pelecanimimus,[6] as well as several taxa (Euronychodon, Paronychodon, and Richardoestesia) known from teeth; known avians are the enantiornitheans Concornis, Eoalulavis, and Iberomesornis.[9] A single non-theropod dinosaur, the ornithischian Mantellisaurus, has been identified from Las Hoyas.[10] Crocodyliforms are represented by the gobiosuchid Cassissuchus, and trackways presumably left by goniopholidids.[6] Lepidosaurs from Las hoyas include the arboreal taxon Scandensia,[11] and the characteristically small Jucaraseps.[12] The exceptionally preserved eutriconodont mammal Spinolestes comes from Las Hoyas.[13] An albanerpetontid amphibian, Celtedens, is known. Roughly twenty species of chondrichthyans (cartilaginous fishes), coelacanths, and actinopterygians (ray-finned fishes), including species previously thought to be exclusively saltwater, constitute the known fish fauna of Las Hoyas.[6][14] The invertebrate fauna of Las Hoyas is represented primarily by insects, and especially by aquatic beetles.[6]
