Posts Tagged ‘omnivore’
Name: »dawn bird«
Length: 50 cm
Height: 20 cm
Weight: 500 g
Time: Jurassic (160 MYA)
Location: Asia (China)
Aurornis (pronounced; or-ROAR-niss ) is an extinct genus of dinosaurs from the Jurassic period of China. The genus Aurornis contains a single known species, Aurornis xui Aurornis xui may be the most basal (“primitive”) avialan dinosaurs known to date, and it is one of the earliest avialan found to date. The fossil evidence for the animal pre-dates that of the famous Archaeopteryx lithographica, often considered the earliest bird species, by about 10 million years.
Aurornis xui was first described and named by Pascal Godefroit, Andrea Cau, Hu Dong-Yu, François Escuillié, Wu Wenhao and Gareth Dyke in 2013. The generic name is derived from the Latin word aurora, meaning “daybreak” or “dawn”, and theAncient Greek ὄρνις (órnis) meaning “bird”. The specific name, A. xui, honors Xu Xing.
Aurornis was described from a sedimentary rock fossil in 2013. The fossil was purchased from a local dealer who said it had been unearthed in Yaoluguo in western Liaoning, China. Subsequent analysis confirmed it came from the Tiaojishan Formation, which has been dated to the late Jurassic period (Oxfordian stage), approximately 160 million years ago. The fossil features traces of downy feathers along the animal’s tail, chest, and neck. It was only partially prepared at the time of purchase with the feathers not showing, and bore no signs of forgery.
On 7th June 2013, however, Science Magazine published an article which noted that Pascal Godefroit, the paleontologist who led the team that described Aurornis, reported that he is uncertain if the fossil material came from Liaoning province’s 160-million-year-old Tiaojishan Formation, as the information provided by the fossil dealer indicated, or from the province’s 125-million-year-old Yixian Formation, which is known to have produced several ancient bird fossils. The failure to secure rigorous provenance information cats doubt on the claim that Aurornis is 160 million years old and predates Archeopteryx. Godefroit’s team will attempt to confirm the specimen’s provenance, and its age, by conducting mineralogical and botanical analysis on the shale slab and then publishing their findings.
Aurornis was roughly the size of a modern pheasant – 50 cm (20 in) in length from beak to tail tip. It had claws and a long tail. Its leg bones are similar to those of Archaeopteryx, but overall its bone structure is more primitive. The absence of larger feathers suggests A. xui was unable to fly. Aurornis lived roughly 160 million years ago, roughly 10 million years prior to Archaeopteryx, which often has been described as the first bird.
A phylogenetic analysis of Aurornis published in 2013 found that it belongs in the bird lineage, in a more basal position than Archaeopteryx. The analysis was based on “almost 1,500 [anatomical] characteristics.”
The classification of A. xui as a bird is somewhat contentious, however, due to the various differing definitions of the word “bird”. Recent discoveries “[emphasize] how grey the dividing line is between birds and [non-avian] dinosaurs”, says Paul Barrett of the Natural History Museum in London. “There’s such a gradation in features between them that it’s very difficult to tell them apart … [Aurornis xui] is certainly an older member of the bird lineage than Archaeopteryx, and it’s fair to call it a very primitive bird. But what you call a bird comes down to what you call a bird, and a lot of definitions depend on Archaeopteryx.” Bird evolution specialist Lawrence Witmer called the new analysis compelling, but said it remains difficult to distinguish birds from birdlike dinosaurs: “All of these little feathered species running and flapping around … were all very similar.”
American paleontologist Luis Chiappe said that A. xui’s forelimb is too short to be a true bird. It “is very birdlike, but it is not yet a bird,” he concluded.
Genus: Aurornis Godefroit et al., 2013
Type species: Aurornis xui / Godefroit et al., 2013
Name: »Wulate dragon«
Length: 1, 5 m
Height: 0,6 m
Weight: 29 kg
Time: Cretacous (84-71 MYA)
Location: Asia (China)
Wulatelong (pronounced: Woo-la-tuh-long ) is an extinct genus of basal oviraptorid dinosaur known from the Late Cretaceous Wulansuhai Formation (Campanian stage) of Bayan Mandahu, Linhe District of Inner Mongolia, northern China. It contains a single species, Wulatelong gobiensis. The genus name combines the name of the region Wulate with the Chinese word long, “dragon”. It consists of a fairly complete skeleton lying in connection with skull and mandibles. Have been preserved: the lower part of the right side of the skull, skull elements of the roof, the back of the right mandible, eleven vertebrae, sixteen tail vertebrae, the left belt with left front leg, a dislocated right shoulder girdle, the right pelvis and right leg. Wulatelong oviraptoride is a fairly small, with a body length of about five feet and an estimated weight of twenty-nine kilograms. The femur is 255 millimeters long.
Here we report a new oviraptorid taxon based on a specimen collected from the Upper Cretaceous Wulansuhai Formation of Bayan Mandahu, Linhe, China. This new taxon is distinguishable from other oviraptorid species by the following unique features: the ventral extremity of the large and elongate external naris is located below the mid-height of the premaxilla, the strap-like jugal process of the maxilla extends well beyond the preorbital bar posteriorly and overlaps the jugal, and the anterodorsal process of the surangular is basally constricted in
lateral view. Although diagnosable as an oviraptorid, this new taxon possesses several plesiomorphic features absent in other oviraptorids but reminiscent of more basal oviraptorosaurs, suggesting a relatively basal position within the Oviraptoridae. The infratemporal fenestra has a narrow dorsal border, the anterior and posterior processes of the lacrimal are relatively long, the ectopterygoid is located relatively posteriorly, the external mandibular fenestra is comparatively posterior in position, the scapula is relatively short
and slender, the pubic peduncle of the ilium is both more ventrally extended and much wider anteroposteriorly than the ischial peduncle, the ischium is relatively short, and metatarsal III is compressed between metatarsals II and IV. This taxon, Wulatelong gobiensis gen. et sp. nov., is therefore inferred to be a basal oviraptorid. A preliminary analysis of the Bayan Mandahu dinosaur fauna supports the view that the Bayan Mandahu strata are the oldest Upper Cretaceous red beds exposed in the Gobi area of the Mongolian Plateau.
Genus: Wulatelong Xu et al., 2013
Type species: Wulatelong gobiensis Xu et al., 2013
Name: »Ganzhou lizard«
Length: 2 m
Height: 0,9 m
Weight: 40 kg
Time: Cretaceous (71-68,5 MYA)
Location: Asia (China)
Ganzhousaurus (pronounced: kan-jo-SOR-us ) is an extinct genus of oviraptorine oviraptorid dinosaur known from the Late Cretaceous Nanxiong Formation of Nankang County, Ganzhou City of Jiangxi Province, southern China. It contains a single species, Ganzhousaurus nankangensis. Ganzhousaurus is derived from “Ganzhou” (for Ganzhou City) and the Greek “sauros” (lizard). The species epithet, nankangensis, is derived from “Nankang” (for Nankang County) and the Latin “-ensis” (from, place of origin). The holotype (SDM 20090302) is a partial skeleton including part of the lower jaw, some tail vertebrae, fragments of the pelvis and limbs, and a foot.
The holotype of Ganzhousaurus is a pretty hefty animal with a body length of about two meters, indicating a weight of about 40 kilograms.
This paper describes a new oviraptorid dinosaur taxon, Ganzhousaurus nankangensis gen. et sp. nov., based on a specimen collected from the Upper Cretaceous Nanxiong Formation of Nankang County, Ganzhou City, Jiangxi Province, southern China. This new taxon is distinguishable from other oviraptorids based on the following unique combination of primitive and derived features: relatively shallow dentary; absence of fossa or pneumatopore on lateral surface of dentary; weakly downturned anterior mandibular end; shallow depression immediately surrounding anterior margin of external mandibular fenestra; external mandibular fenestra subdivided by anterior process of surangular; dentary posteroventral process slightly twisted and positioned on mandibular
ventrolateral surface; shallow longitudinal groove along medial surface of dentary posteroventral process; angular anterior process wider transversely than deep dorsoventrally; sharp groove along ventrolateral surface of angular anterior process; ventral border of external mandibular fenestra formed mainly by angular; ventral flange along distal half of metatarsal II; and arctometatarsal condition absent. Phylogenetic analysis places Ganzhousaurus nankangensis gen. et sp. nov. in the clade Oviraptoridae, together with Oviraptor, Citipati, Rinchenia and the unnamed Zamyn Khondt oviraptorid.
The midfoot is, with a length of fourteen inches against the relatively short, with respect to the toes.
Ganzhousaurus placed despite the many basic features in Oviraptoridae by the descriptors, after an exact cladistic analysis.
Genus: Ganzhousaurus Wang et al., 2013
Type species: Ganzhousaurus nankangensis, Wang et al., 2013
Name: »early Chinese wing«
Length: 30 cm
Height: 15 cm
Weight: 100 g
Diet: carnivore, omnivore
Time: Jurassic (161-156 MYA)
Location: Asia (China)
Eosinopteryx (pronounced: EE-oh-si-NOP-ter-ix ) is an extinct genus of basal troodontid theropod dinosaur known from the Late Jurassic Tiaojishan Formation of western Liaoning Province, China. It contains a single species, Eosinopteryx brevipenna.
Eosinopteryx brevipenna is known from a single fossil specimen representing the nearly complete skeleton of a subadult or adult individual. The specimen is very small for a non-avialan dinosaur, measuring about 30 centimetres (12 in) long. Unlike most other troodontids, the snout was very short, shorter than the diameter of the eye socket. The wings were about the same size as those of the related Anchiornis, with the primary wing feathers being longer than the humerus (upper arm bone). An unusual arrangement of the wing bones would have prevented any flapping motion. The tail was very short compared to most other members of the group Deinonychosauria, and unlike other known deinonychosaurs, the feet and toes were very slender, lacking highly curved claws for predation. Unusually, the tail seems to have completely lacked complex vaned feathers (rectrices), and the lower tarsals and feet appear to have been featherless, unlike some related species with “hind wings” on the lower legs and feet.
A researcher from the University of Southampton said the discovery of Eosinopteryx suggests “that the origin of flight was much more complex than previously thought”.
Genus: Eosinopteryx Godefroit et al., 2013
Type species: Eosinopteryx brevipenna, Godefroit et al., 2013
Name: »beautiful dragon«
Length: 25 – 50 cm
Height: 30 cm
Weight: 0,5 – 1 kg
Time: Cretaceous (99-66 MYA)
Location: Asia (China)
Yulong (pronounced: yuh-long) is an extinct genus of derived oviraptorid theropod dinosaur known from the Late Cretaceous Qiupa Formation of Henan Province, central China. It contains a single species, Yulong mini. It is known from many juvenile specimens that represent some of the smallest known oviraptorids.
Specimens of Yulong were collected near Qiupa Town in Luanchuan County, Henan Province, from the Qiupa Formation. The exact geological age of the Qiupa Formation is unknown, but it probably dates to the Late Cretaceous based on the presence of oviraptorids (Yulong), dromaeosaurids (Luanchuanraptor), ornithomimids (Qiupalong) and other, undescribed, derived dinosaur specimens.
Yulong was first described and named by Junchang Lü, Philip J. Currie, Li Xu, Xingliao Zhang, Hanyong Pu and Songhai Jia in 2013 and the type species is Yulong mini. The generic name is derived from Chinese (Yù), the one-character abbreviation of Henan Province, in reference to the occurrence of the genus, and from lóng meaning “dragon” – a suffix commonly used to name Chinese dinosaurs like the Greek saurus is in the West. The specific name, mini, refers to the small size of the specimens.
Yulong is based on a syntype series of five specimens: HGM 41HIII-0107: an exceptionally well-preserved skeleton with a skull and lower jaws that is housed in the Henan Geological Museum, only lacking the skull and the neck base; HGM 41HIII-0108: a skull lacking the lower jaws; HGM 41HIII-0109: a partial skeleton with skull and lower jaws; HGM 41HIII-0110: a partial skull with lower jaws and some neck vertebrae; and HGM 41HIII-0111: a left ilium. Additional finds have been mentioned in the describing paper. One exceptionally preserved embryo (within an egg) is HGM 41HIII-0301, which came from a nest of 26 eggs.
While oviraptorids were generally one to eight metres in body length, Yulong was described as “chicken-sized” by its describers. Most of the Yulong individuals had a total body length of a quarter to half a meter, making them some of the smallest known oviraptorids.
The describing authors established some diagnostic traits. The front upper corner of the fenestra antorbitalis and the rear upper corner of the bony nostril are positioned at about the same height. The premaxilla shows a distinctive opening below and in front of the nostril. The rear upper process of the premaxilla touches the upper rim of the fenestra antorbitalis but not the front process of the lacrimal; both bones are separated by the nasal bone. The parietal approaches the frontal bone in length. At the fourth and fifth neck vertebrae, the rear edge of the vertebral centrum forms a straight line between the postzygapophyses. The thigh bone is longer than the ilium.
According to the authors, the hindlimb proportions of oviraptorids do not essentially change during growth, indicating a more sedentary lifestyle and thus probably herbivory.
A phylogenetic analysis performed by the describers found Yulong to be more derived than the gigantic oviraptorid Gigantoraptor erlianensis, and less derived than (as a sister taxon to) the clade formed by the Oviraptorinae and the “Ingeniinae”. However, the describers cautioned that thephylogenetic position of Yulong is still uncertain, because younger specimens tend to display more basal traits than adult specimens that are unknown for Yulong.
Genus: Yulong, Lü et al., 2013
Type species: Yulong mini, Lü et al., 2013
An international team of scientists, including PhD student Stephan Lautenschlager and Dr Emily Rayfield of the University of Bristol, found that the senses of smell, hearing and balance were well developed in therizinosaurs and might have affected or benefited from an enlarged forebrain. These findings came as a surprise to the researchers as exceptional sensory abilities would be expected from predatory and not necessarily from plant-eating animals.
Therizinosaurs are an unusual group of theropod dinosaurs which lived between 145 and 66 million years ago. Members of this group had evolved into up to 7 m (23 ft) large animals, with more than 50 cm (20 in) long, razor-sharp claws on their forelimbs, elongated necks and a coat of primitive, down-like feathers along their bodies. Although closely related to carnivorous dinosaurs such as Tyrannosaurus rex and Velociraptor, and in spite of their bizarre appearance, therizinosaurs were probably peaceful herbivores.
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Name: »March (area) thief«
Length: 0,5 – 2 m
Height: 1 m
Weight: 20 kg
Time: Cretaceous (124 MYA)
Location: North America
Martharaptor is an extinct genus of basal therizinosauroid theropod from the Lower Cretaceous of Utah.
The finds were made 15 km south-east of the Green River in eastern Utah. It was later investigated by the association of amateur paleontology of Utah Friends of Paleontology , led by Lindsay Zanno and Robert Thomas Becker. It was established that the found skeleton belongs to a small theropod. In 2012, the type species Martharaptor greenriverensis was described by Philip Senter, James Kirkland and Donald DeBlie. The genus name is derived from the March Hayden, area, where it was found and from Latin raptor – “robber.” The specific epithet refers to the town of Green River.
Holotype, UMNH VP 21400, was found in the layers of a geological formation Cedar Mountain , which dates from the early Aptian, about 124 million years. It includes vertebrae neck, back and tail bone blades, buttocks, pubic bones of the forearm and hind limbs. It also includes several well-preserved claw phalanges forelimbs. The finds were located in an area of one square meter at a depth of twenty centimeters. Quality of the fossil is pretty bad. The morphology of the front and hind limbs shows that the sample is different from other theropods from the formation Cedar Mountain and the previously described therizinosauroids.
Martharaptor greenriverensis is a small bipedal theropod . The appearance of a dinosaur is hard to determine, presumably it resembled basal therizinosauroids. Height of holotype is about half to two meters, and weighs about 40 pounds. In this case, the tail had been relatively short and the neck relatively long.
Martharaptor greenriverensis is placed in the group of Therizinosauroidea . According to cladistic analysis, it found itself in the basal position, above Beipiaosaurus , but below Alxasaurus in the pedigree. Scientists point out that the reasons for this placement is because of the small number of finds are not very convincing. A new sample is added to a known dinosaur fauna from Yellow Cat Member , formation Cedar Mountain , which includes the same basal theropod Falcarius utahensis . If the phylogenetic position is true, it is also added to the known species of the superfamily Therizinosauroidea .
For more scientific info click HERE.
Senter et al., 2012
Type species: Martharaptor greenriverensis
Senter et al., 2012
Name: “crane – like”
Length: 1 m
Height: 0,5 m
Weight: 5 kg
Time: Cretaceous (125 MYA)
Location: Asia (China)
Hexing (meaning: Hexing, in Mandarin, means “like a crane” (the bird not the machine). The species epithet, qingyi, means “with thin wings”, also in Mandarin. ) is an extinct genus of basal ornithomimosaur dinosaur known from the Early Cretaceous Yixian Formation (early Valanginian to early Barremian stage) of northeastern China. It contains a single species, Hexing qingyi. A phylogenetic analysis found Hexing to be more derived than Pelecanimimus, but less derived than Beishanlong, Garudimimus, Harpymimus and Ornithomimidae. Shenzhousaurus, also from the Yixian Formation, was found in a polytomy with Hexing. The remains of Hexing were discovered at the Xiaobeigou locality in the lowest Yixian Formation, Lujiatun, Shangyuan, Beipiao City, Western Liaoning Province, China by a local farmer who actually began to prepare the fossils himself. Bruised and battered, the remains were carted back to the Geological Museum of the Jilin University, Changchun, Jilin Province, where they are now housed, and painstakingly restored. Hexing is the second dinosaur from this area, behind Shenzhousaurus orientalis (Ji et al, 2003). The holotype (JLUM-JZ07b1) is an incomplete adult specimen: a partial skull, a portion of the neck, and limb bones, including a 135mm long femur which showed that Hexing is much smaller than other ornithomimosaurs.
In the early twenty-first century, a local farmer at Xiaobeigou in Liaoning discovered the skeleton of a small theropod. He prepared the fossil himself, trying to enhance its value by restaurating damaged bones and adding fake parts. Eventually the specimen was obtained by the Geological Museum of Jilin University and more expertly prepared, during which process the added parts were again removed.
In 2012, the type species Hexing qingyi was named and described by Jin Liyong, Chen Jun and Pascal Godefroit. The generic name means “like a crane” in Chinese. The specific name means “with slender wings”.
The holotype, JLUM-JZ07b1, was found in fluvial deposits of the lower Yixian Formation, which have a highest possible age of 139 million years and a lowest of 128 million years and thus date from some time in the early Valanginian to early Barremian stage. It consists of a partial skeleton, containing the skull, the lower jaws, a series of five cervical vertebrae, the shoulder girdle and the majority of both forelimbs and hindlimbs. The remains have not been well preserved. The specimen represents a subadult or adult individual.
The holotype specimen consists of the remains of a small individual. Because most of the vertebral column is absent, its body length cannot be directly determined, but a comparison can be made with the previously smallest known ornithomimosaur, the 1.6 metres long Shenzhousaurus, which has a thighbone length of 191 millimetres, while the femur length of Hexing is 135 millimetres. Such a small body size was among ornithomimosaurs up till now only known from juveniles but the holotype is not a young animal as is shown by the complete fusion of the skull bones, the neck ribs, the scapulocoracoid and the ankle bones.
The describers determined some autapomorphies of Hexing, its unique derived traits. The snout tip reaches downwards in front of the lower jaws, so deeply that the roof of the mouth at this point is at a level with the bottom edge of the lower jaw. The fossa antorbitalis, a depression on the side of the maxilla, covers almost the entire outer surface of that bone. The parietal bones are joint at their midline in a crest. The large bone extensions at the back of the skull, the processus paroccipitales, are hanging down below the level of the foramen magnum. In the lower jaw, the dentary has an opening in its side. The formula for the phalanges of the hand is 1-2-3-0-0 or 2-3-3-0-0 — or 0-1-2-3-0/0-2-2-3-0 if the three fingers of the hand are interpreted as the second, third and fourth. The upper phalanges of the second and third (or third and fourth) finger are elongated with more than 75% of the length of the corresponding metacarpal. The lower leg is relatively long with the tibiotarsus having 137% of the length of the thighbone.
The skull of Hexing is relatively large with a length of 136 millimetres. It is elongated and triangular in side view. The snout is appending with a slight kink above the middle of the fossa antorbitalis, which at this point is reinforced by a distinctive vertical bone strut, a pila interfenestralis dividing the depression in two halves: at its rear an oval skull opening, the fenestra antorbitalis, pierces the surface and at its front the uniquely large and deep hollowing out of the maxilla side is visible, in which another opening, the fenestra maxillaris, might have been present, though this is uncertain because of damage. The front of the snout consists of a small praemaxilla, continuing the line of the nasals downwards and forming a small upper beak in front of the lower jaws. The beak is separated by a low notch from the lower maxilla edge, which is toothless.
The front of the lower jaw is low and slightly upward curving. In the left dentary the remains of three or four low conical teeth are visible; of these damage obscures most detail. The dentary has a small opening in the side surface. The higher back of the lower jaw seems to show a much larger opening, but this is an artefact caused by the original inexpert preparation damaging the thin bone surface of an extensive mandibular fossa. A real and much smaller external mandibular fenestra is present in front of this. Neither the lower jaw nor the upper jaw form cutting edges.
The cervical vertebrae are elongated with low spines. They are pneumatised and have large triangular diapophyses and postzygapophyses.
The shoulder blade is elongated and narrow, without expanded upper end. The humerus is somewhat shorter than the shoulder blade and is slender. Its shaft is not twisted. The bones of the lower arm are likewise elegant and straight. A large part of the over ten centimetres long hand has been preserved; this shows a configuration that is fundamentally different from that of related species. The describers have carefully checked whether this could have been caused by falsifications during the original preparation but could find no sign of any tampering. As a result the identification of the respective parts is highly problematical. As preserved the hand shows three rows of elements: the first with two bones and the second and third with four bones. If these would represent both phalanges and metacarpals, these series should have three, four and five elements, however: from the first and third row a bone is missing. The authors considered it most likely that in the first finger the upper phalanx was completely reduced, that is: naturally absent. However, as this would imply that the claw attached directly to the metacarpal and this metacarpal would then be exceptionally long, they allowed for the alternative possibility that the visible element was the first phalanx and that the metacarpal was lacking because of an incompleteness of the fossil. In the third finger the number of phalanges seemed almost certainly reduced from four to three because the place of the two normal short upper phalanges is taken by a single long element. The description of this situation is complicated by the fact that the describers follow the hypothesis of Xu Xing that with Tetanurae — including birds and Hexing — the first, second and third fingers are actually the second, third and fourth. This would in the standard terminology make the formula of the phalanges 1-3-3-0-0 or alternatively 2-3-3-0-0 and following the hypothesis of Xu 0-1-3-3-0 or 0-2-3-3-0. In general the phalanges are slender and elongated. The hand claws are relatively large and curved, with a flatter underside.
The thighbone is strongly curved, with a convex anterior end. The tibia is 185 millimetres long and thus very elongated compared with the femur; only some juvenile ornithomimid specimens have relatively longer tibiotarsi. The first metatarsal is half as long as the second, the longest of the foot. The foot claws are flatter than the hand claws.
The describers assigned Hexing a basal position in the Ornithomimosauria. Their phylogenetic analysis found Hexing to be more derived than Pelecanimimus, but less derived than a clade consisting of Beishanlong, Harpymimus, Garudimimus and the Ornithomimidae. The small forms Hexing and Senzhousaurus are the oldest known ornithomimosaurians, as Pelecanimimus dates from the late Barremian. Because this latter species is more basal, the authors considered this a strong indication that a land bridge had formed between Europe and Asia long before the Aptian, the normally assumed date for this event.
Genus: Hexing Jin, Chen & Godefroit, 2012
Type species: Hexing qingyi Jin, Chen & Godefroit, 2012
Name: »ork? mimic«
Time: Cretaceous (84-65 MYA)
Location: North America
“Orcomimus” (Pronounced or-coh-MEEM-us) is the name given to an as yet undescribed genus of dinosaur from the Late Cretaceous period around 84–65 million years ago. The dinosaur was an ornithomimid which lived in what is now South Dakota, in the United States. The type was coined by Michael Triebold in 1997, but has never been formally described and is currently a nomen nudum.
“Orcomimus” was a bipedal carnivore or omnivore, but the dinosaur is known from only a pelvis and a hindlimb. “Orcomimus” is thought to be relatively advanced for other ornithomimids at the time, although this is hard to tell from the limited amount of specimens found of the dinosaur.
Name: »plain runner«
Lenght: 1,5 m
Height: 0,5 m
Weight: 10 kg
Time: Triassic (230-228 MYA)
Location: South America (Brasil)
“Pampadromaeus” is a genus of basal sauropodomorph dinosaurs known from the Triassic of Rio Grande do Sul, southern Brazil.
“Pampadromaeus” is known only from the holotype specimen ULBRA-PVT016, a disarticulated, partial but well preserved skeleton from a single individual which includes most of the skull bones and the lower jaws; dorsal, sacral and caudal vertebrae; elements of the shoulder girdle and the forelimbs, an ilium and elements of the hindlimbs. It was collected in the upper Hyperodapedon biozone from the Alemoa Member of the Santa Maria Formation (Rosario do Sul Group) in the “Janner” (also known as “Varzea do Agudo”) locality, geopark of Paleorrota, dating to the Carnian faunal stage of the early Late Triassic, about 230-228 million years ago.
“Pampadromaeus” was a small bipedal animal. It shows a mosaic of basal and derived traits. It differs from other sauropodomorphs by a combination of characters. Some of these are shared with some members of the sister group of the Sauropodomorpha, the Theropoda: the premaxilla is pointed downwards forming a subnarial gap with the maxilla and the anterior-most teeth are unserrated; in the location where with theropods the fenestra promaxillaris is positioned, a small depression is present. Basal traits consist of a large skull, a short thighbone, the possession of just two sacral vertebrae and the presence of fifteen teeth in the pterygoid. While the skull of Pampadromaeus is long, low and generally resembles those of sauropodomorphs, the newly described dinosaur had different kinds of teeth in the jaw. Leaf-shaped teeth thought to correspond to herbivory were set in the front, while an array of short, recurved teeth often associated with carnivory followed toward the back of the mouth. Perhaps Pampadromaeus was an omnivorous dinosaur not yet fully committed to a life of chewing on plants. The anatomy of the rest of the dinosaur’ approximately four-foot-long body is consistent with a unique and varied lifestyle. Pampadromaeus had long legs and comparatively short arms, which hint that the dinosaur was an obligate biped. It seems unlikely that Pampadromaeus switched between walking on two legs and all fours as in later sauropodomorphs.
There were four teeth in the premaxilla and about twenty in both the maxilla and the lower jaw for a total of eighty-eight. The teeth were large, elongated, lanceolate, slightly recurved, sharply pointed and coarsely serrated. The lower leg was much longer than the thighbone, indicating “Pampadromaeus” was good runner.
“Pampadromaeus” is currently a nomen nudum, the name having appeared only online and not yet officially in print. It is set to be named by Sergio F. Cabreira, Cesar L. Schultz, Jonathas S. Bittencourt, Marina B. Soares, Daniel C. Fortier, Lucio R. Silva and Max C. Langer, with the expected type species of Pampadromaeus barberenai. The generic name is derived from Quechua pampa, “plain”, in reference to the present landscape of the site, and Greek dromeus, “runner”, referring to the cursorial habits; the Latinised spelling variant dromaeus is used. The specific name honours the Brazilian paleontologist Mario Costa Barberena.
“Pampadromaeus” was found to be a basal sauropodomorph in four different cladistic analyses. The describers emphasized however, that this position was not strongly supported, showing the difficulties of determining the affinities of such early forms with the basal Dinosauromorpha, Saurischia, Sauropodomorpha and Theropoda.
Species: P. barberenai Cabreira et al., 2011