Pilmatueia

Last updated

Pilmatueia
Temporal range: Early Cretaceous, Valanginian
O
S
D
C
P
T
J
K
Pg
N
Pilmatueia faundezi Pilmatueia skeletal.jpg
Pilmatueia faundezi
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Sauropodomorpha
Clade: Sauropoda
Superfamily: Diplodocoidea
Family: Dicraeosauridae
Genus: Pilmatueia
Coria et al., 2019
Type species
Pilmatueia faundezi
Coria et al., 2019

Pilmatueia is a diplodocoid sauropod belonging to the family Dicraeosauridae that lived in Argentina during the Early Cretaceous. Its type and only species is Pilmatueia faundezi. Pilmatueia was probably closely related to other South American dicraeosaurids such as Amargasaurus . Pilmatueia had relatively pneumatic vertebrae compared to other dicraeosaurids, which were otherwise characterized by a reduction in pneumaticity relative to other sauropods. Pilmatueia dates to the Valanginian, an age of the Cretaceous period for which dinosaur faunas are poorly known.

Contents

Discovery and naming

Fossils of Pilmatueia faundezi were discovered in Neuquén Province, Argentina, at a site called Pilmatué. [1] Fossil excavations at Pilmatué began in 2009, [2] and the discovery of dicraeosaurid remains at Pilmatué was first announced in 2012, at a paleontology conference in Buenos Aires. [3] [1] In 2019, [lower-alpha 1] Rodolfo Coria and colleagues named the new genus and species Pilmatueia faundezi. The genus name refers to the Pilmaté locality, and the species epithet recognizes Ramón Faúndez, manager of the Museo Municipal de Las Lajas, who supported the excavation project. The discovery of Pilmatueia in the Valanginian, an age of the Early Cretaceous with poorly known dinosaur faunas, helped fill a gap in the dicraeosaurid fossil record between Jurassic dicraeosaurids and the later Amargasaurus. [1]

Fossil specimens

Pilmatueia faundezi fossils have been found in the Mulichinco Formation of Argentina. Known material includes the holotype, MLL Pv-005, a posterior dorsal vertebra; [1] the paratype MLL-Pv-002, a posterior cervical vertebra; MLL-Pv-010, a partial skeleton including cervical vertebrae, dorsal vertebrae, ribs, a caudal vertebra, and incomplete scapulae; [4] and other isolated vertebrae. [1] Other dicraeosaurid fossils have been found in the Mulichinco Formation, including a femur [1] and a natural cranial endocast, [5] and it is possible that they also belong to Pilmatueia faundezi. [1] [6]

Description

Pilmatueia, like other dicraeosaurids, had tall, deeply forked neural spines on its cervical and dorsal vertebrae. The cervical neural spines were low compared to those of Amargasaurus and Bajadasaurus. [4] As in most dicraeosaurids, the neural spines were inclined forward, unlike the backswept neural spines seen in Amargasaurus. [4] Unlike most dicraeosaurids, which have reduced vertebral pneumaticity compared to other sauropods, the cervical vertebrae of Pilmatueia contain pneumatic chambers. However, as in other dicraeosaurids, the dorsal centra lack the pneumatic foramina that are characteristic of most sauropods. [7] [8] The cervical centra have ventral keels that are forked anteriorly and posteriorly, unlike the simple midline keels typical of other diplodocoids. [4] A foramen is present on the proximal end of the cervical ribs, which probably is a nutrient foramen and not a pneumatic structure. The anterior dorsal vertebrae show an autapomorphic ridge on the anterior centrodiapophyseal lamina. [1] Even the posterior dorsal vertebrae had forked neural spines, as in its close relative Amargasaurus, and unlike other dicraeosaurids in which forking of the neural spines only extended into the middle dorsal vertebrae. [4] The posterior dorsal vertebrae show an autapomorphic pair of deep fossae near the bases of the neural spines. [1] The scapula has a ridge on the medial surface near the acromion, which is not present in other dicraeosaurids. [4]

Classification

Dicraeosauridae

Suuwassea

Lingwulong

Dicraeosaurus

Brachytrachelopan

Amargasaurus

Amargatitanis

Bajadasaurus

Pilmatueia

Phylogenetic position of Pilmatueia within Dicraeosauridae, following an analysis by Windholtz et al. that recovered their favored hypothesis of South American dicraeosaurid monophyly, [4] with South American dicraeosaurids highlighted in red.

Pilmatueia is a dicraeosaurid sauropod. Its phylogenetic position within Dicraeosauridae is uncertain, with some analyses finding it to be closely related to Amargasaurus [1] [4] and other analyses finding it to be a more basal dicraeosaurid, outside the clade uniting Dicraeosaurus, Brachytrachelopan, and Amargasaurus. [9] [10] [4] Windholz et al. argued that, while phylogenetic analyses do not currently provide clear resolution for its affinities, on chronological and biogeographic grounds it is most likely to belong to a clade uniting the South American dicraeosaurids. [4]

Paleoecology

Pilmatueia lived in what is now Argentina during the Valanginian age of the Cretaceous, and is a member of the Bajadan faunal assemblage. It coexisted with an indeterminate species of diplodocid [6] and the small, early carcharodontosaur Lajasvenator . [2] Podocarp trees were present in the ecosystem. [11]

Footnotes

  1. The article was released online on 29 August 2018, but formally published in the January 2019 issue of the journal.

Related Research Articles

<i>Argentinosaurus</i> Late Cretaceous giant sauropod dinosaur genus

Argentinosaurus is a genus of giant sauropod dinosaur that lived during the Late Cretaceous period in what is now Argentina. Although it is only known from fragmentary remains, Argentinosaurus is one of the largest known land animals of all time, perhaps the largest, measuring 30–35 metres (98–115 ft) long and weighing 65–80 tonnes. It was a member of Titanosauria, the dominant group of sauropods during the Cretaceous. It is widely regarded by many paleontologists as the biggest dinosaur ever, and perhaps lengthwise the longest animal ever, though both claims have no concrete evidence yet.

Agustinia is a genus of sauropod dinosaur from the Early Cretaceous of South America. The genus contains a single species, Agustinia ligabuei, known from a single specimen that was recovered from the Lohan Cura Formation of Neuquén Province in Argentina. It lived about 116–108 million years ago, in the Aptian–Albian stages of the Early Cretaceous Period.

Amazonsaurus is a genus of diplodocoid sauropod dinosaur from the Early Cretaceous Period of what is now South America. It would have been a large-bodied quadrupedal herbivore with a long neck and whiplash tail. Although more derived diplodocoids were some of the longest animals ever to exist, Amazonsaurus was probably not more than 12 meters (40 ft) long. Gregory S. Paul estimated in 2010 its weight at 5000 kg.

<i>Amargasaurus</i> Dicraeosaurid sauropod dinosaur genus from the Early Cretaceous period

Amargasaurus is a genus of sauropod dinosaur from the Early Cretaceous epoch of what is now Argentina. The only known skeleton was discovered in 1984 and is virtually complete, including a fragmentary skull, making Amargasaurus one of the best-known sauropods of its epoch. Amargasaurus was first described in 1991 and contains a single known species, Amargasaurus cazaui. It was a large animal, but small for a sauropod, reaching 9 to 13 meters in length. Most distinctively, it sported two parallel rows of tall spines down its neck and back, taller than in any other known sauropod. In life, these spines could have stuck out of the body as solitary structures that supported a keratinous sheath. An alternate hypothesis, now more favored, postulates that they could have formed a scaffold supporting a skin sail. They might have been used for display, combat, or defense.

<i>Euhelopus</i> Extinct genus of dinosaurs

Euhelopus is a genus of sauropod dinosaur that lived between 145 and 133 million years ago during the Berriasian and Valanginian stages of the Early Cretaceous in what is now Shandong Province in China. It was a large quadrupedal herbivore. Like sauropods such as brachiosaurs and titanosaurs, Euhelopus had longer forelegs than hind legs. This discovery was paleontologically significant because it represented the first dinosaur scientifically investigated from China: seen in 1913, rediscovered in 1922, and excavated in 1923 and studied by T'an during the same year. Unlike most sauropod specimens, it has a relatively complete skull.

<span class="mw-page-title-main">Dicraeosauridae</span> Extinct family of dinosaurs

Dicraeosauridae is a family of diplodocoid sauropods who are the sister group to Diplodocidae. Dicraeosaurids are a part of the Flagellicaudata, along with Diplodocidae. Dicraeosauridae includes genera such as Amargasaurus, Suuwassea, Dicraeosaurus, and Brachytrachelopan. Specimens of this family have been found in North America, Asia, Africa, and South America. In 2023, a dicraeosaurid fossil was discovered in India for the first time. Their temporal range is from the Early or Middle Jurassic to the Early Cretaceous. Few dicraeosaurids survived into the Cretaceous, the youngest of which was Amargasaurus.

<i>Brachytrachelopan</i> Extinct genus of dinosaurs

Brachytrachelopan is a short-necked sauropod dinosaur from the Late Jurassic of Argentina. The holotype and only known specimen was collected from an erosional exposure of fluvial sandstone within the Cañadón Calcáreo Formation on a hill approximately 25 kilometres (16 mi) north-northeast of Cerro Cóndor, Chubut Province, in west-central Argentina, South America. Though very incomplete, the skeletal elements recovered were found in articulation and include eight cervical, twelve dorsal, and three sacral vertebrae, as well as proximal portions of the posterior cervical ribs and all the dorsal ribs, the distal end of the left femur, the proximal end of the left tibia, and the right ilium. Much of the specimen was probably lost to erosion many years before its discovery. The type species is Brachytrachelopan mesai. The specific name honours Daniel Mesa, a local shepherd who discovered the specimen while searching for lost sheep. The genus name translates as "short-necked Pan", Pan being the god of the shepherds.

<i>Neuquensaurus</i> Extinct genus of dinosaurs

Neuquensaurus is a genus of saltasaurid sauropod dinosaur that lived in the Late Cretaceous, about 80 million years ago in Argentina in South America. Its fossils were recovered from outcrops of the Anacleto Formation around Cinco Saltos, near the Neuquén river from which its name is derived.

<i>Puertasaurus</i> Extinct genus of dinosaurs

Puertasaurus is a genus of sauropod dinosaur that lived in South America during the Late Cretaceous Period. It is known from a single specimen recovered from sedimentary rocks of the Cerro Fortaleza Formation in southwestern Patagonia, Argentina, which probably is Campanian or Maastrichtian in age. The only species is Puertasaurus reuili. Described by the paleontologist Fernando Novas and colleagues in 2005, it was named in honor of Pablo Puerta and Santiago Reuil, who discovered and prepared the specimen. It consists of four well-preserved vertebrae, including one cervical, one dorsal, and two caudal vertebrae. Puertasaurus is a member of Titanosauria, the dominant group of sauropods during the Cretaceous.

Amargatitanis is a genus of dicraeosaurid sauropod dinosaur from the Barremian-age La Amarga Formation of Neuquén, Argentina. It is known from a single, incomplete postcranial skeleton consisting of a partial hindlimb, ischium, and two vertebrae. These remains were unearthed by Argentine paleontologist José Bonaparte in 1983 during an expedition by the Museo Argentino de Ciencias Naturales and later described as a new genus and species, Amargatitanis macni by Sebastián Apesteguía. The genus name comes from the words Amarga, where the fossils were collected, and titanis meaning "titan". Its species name is in reference to the MACN, where the remains are stored.

<i>Overosaurus</i> Extinct genus of dinosaurs

Overosaurus is an extinct genus of sauropod dinosaurs, containing only a single species, Overosaurus paradasorum. This species lived approximately 86 to 84 million years ago during the latter part of the Cretaceous Period in what is now Patagonia. Overosaurus paradasorum was relatively small compared to other sauropods from Patagonia, like the saltasaurids and other aeolosaurines, estimated as approximately 10 m (33 ft). It was a ground-dwelling herbivore.

<i>Katepensaurus</i> Extinct genus of rebbachisaurid dinosaurs

Katepensaurus is an extinct genus of rebbachisaurid sauropod dinosaur known from the Late Cretaceous of south-central Chubut Province of central Patagonia, Argentina. It contains a single species, Katepensaurus goicoecheai.

<i>Leinkupal</i> Extinct genus of reptiles

Leinkupal is a genus of diplodocine sauropod known from the Early Cretaceous of the Bajada Colorada Formation, southeastern Neuquén Basin in the Neuquén Province of Argentina. It contains a single species, Leinkupal laticauda.

<i>Bajadasaurus</i> Genus of sauropod dinosaur

Bajadasaurus is a genus of sauropod dinosaur from the Early Cretaceous epoch of northern Patagonia, Argentina. It was first described in 2019 based on a single specimen found in 2010 that includes a largely complete skull and parts of the neck. The only species is Bajadasaurus pronuspinax. The genus is classified as a member of the Dicraeosauridae, a group of relatively small and short-necked sauropods.

The Bajada Colorada Formation is a geologic formation of the southern Neuquén Province in the Neuquén Basin of northern Patagonia, Argentina. The formation belongs to the Mendoza Group and is Late Berriasian to Early Valanginian in age. The formation is renowned for preserving fossil remains of Bajadasaurus pronuspinax, a genus of dicraeosaurid dinosaurs named after the formation.

Kaijutitan is a genus of basal titanosaur dinosaur from the Sierra Barrosa Formation from Neuquén Province in Argentina. The type and only species is Kaijutitan maui.

<span class="mw-page-title-main">Ernesto Bachmann Paleontological Museum</span> Science museum, Local museum in Neuquén Province, Argentina

The Ernesto Bachmann Paleontological Museum (MEB) in Villa El Chocón, Neuquén Province, Argentina, is a municipal museum dedicated to the paleontology, archaeology and history of Villa El Chocón and its surroundings.

<i>Lajasvenator</i> Genus of carcharodontosaurid (fossil)

Lajasvenator is a genus of carcharodontosaurid dinosaur from the Mulichinco Formation from Neuquén Province in Argentina. The type and only species is Lajasvenator ascheriae. It was probably one of the smallest known allosauroids, being approximately only half the length of Concavenator, about 2.9 m (9.5 ft). Lajasvenator consists of 2 specimens, MLL-PV-Pv-05 and MLL-PV-Pv-07. MLL-PV-Pv-07 preserved the proximal end of a cervical rib that is identical to the 7th cervical rib of the MLL-PV-Pv-05. The origin of Lajasvenator is based on these materials collected from Argentina. Possibly, the early evolutionary stage for the Carcharodontosauridae started with these medium sized predators that later evolved into the heavily built carcharodontosaurs such as Meraxes or Giganotosaurus. Lajasvenator is the oldest Carcharodontosaur from the Cretaceous in South America and a key element for its future evolutionary giants.

<span class="mw-page-title-main">Mulichinco Formation</span> Geological formation in Argentina

The Mulichinco Formation is a geological formation in Argentina. It is Valanginian in age and is predominantly terrestrial, being deposited at a time of marine regression in the Neuquén Basin, and predominantly consists of siliciclastic rocks.

References

  1. 1 2 3 4 5 6 7 8 9 10 Rodolfo A. Coria; Guillermo J. Windholz; Francisco Ortega; Philip J. Currie (2018). "A new dicraeosaurid sauropod from the Lower Cretaceous (Mulichinco Formation, Valanginian, Neuquén Basin) of Argentina". Cretaceous Research. 93: 33–48. doi:10.1016/j.cretres.2018.08.019. S2CID   135017018.
  2. 1 2 Coria, Rodolfo A.; Currie, Philip J.; Ortega, Francisco; Baiano, Mattia A. (2019-11-25). "An Early Cretaceous, medium-sized carcharodontosaurid theropod (Dinosauria, Saurischia) from the Mulichinco Formation (upper Valanginian), Neuquén Province, Patagonia, Argentina". Cretaceous Research. 111: 104319. doi:10.1016/j.cretres.2019.104319. hdl: 11336/122794 . ISSN   0195-6671. S2CID   214475057.
  3. Coria, R. A.; Ortega, F.; Succar, C.; Currie, P.; Koppelhus, E. (2012). "First record of a dicraeosaurid sauropod from the Lower Cretaceous (Valanginian) of Neuquén Basin". Ameghiniana. 49 (4R): R44.
  4. 1 2 3 4 5 6 7 8 9 10 Windholz, Guillermo J; Coria, Rodolfo A.; Bellardini, Flavio; Baiano, Mattia A.; Pino, Diego; Ortega, Francisco; Currie, Philip J. (2022-12-21). "On a dicraeosaurid specimen from the Mulichinco Formation (Valanginian, Neuquén Basin) of Argentina and phylogenetic relationships of the South American dicraeosaurids (Sauropoda, Diplodocoidea)". Comptes Rendus Palevol. 21 (45): 991–1019. ISSN   1631-0683.
  5. Paulina Carabajal, A.; Coria, R.A.; Currie, P.J.; Koppelhus, E.B. (2017-12-12). "A natural cranial endocast with possible dicraeosaurid (Sauropoda, Diplodocoidea) affinities from the Lower Cretaceous of Patagonia". Cretaceous Research. 84: 437–441. doi:10.1016/j.cretres.2017.12.001. ISSN   0195-6671.
  6. 1 2 Gallina, Pablo A.; Apesteguía, Sebastián; Carballido, José L.; Garderes, Juan P. (2022). "Southernmost spiny backs and whiplash tails: flagellicaudatans from South America". In Otero, Alejandro; Carballido, José L.; Pol, Diego (eds.). South American Sauropodomorph Dinosaurs. Cham: Springer International Publishing. pp. 209–236. ISBN   978-3-030-95958-6.
  7. Windholz, Guillermo J.; Coria, Rodolfo A.; Zurriaguz, Virginia L. (2019-11-29). "Vertebral pneumatic structures in the Early Cretaceous sauropod dinosaur Pilmatueia faundezi from northwestern Patagonia, Argentina". Lethaia. 53 (3): 369–381. doi:10.1111/let.12363. ISSN   0024-1164. S2CID   212766423.
  8. Windholz, Guillermo J.; Carballido, José L.; Coria, Rodolfo A.; Zurriaguz, Virginia L.; Rauhut, Oliver W. M. (2022-11-22). "How pneumatic were the presacral vertebrae of dicraeosaurid (Sauropoda: Diplodocoidea) dinosaurs?". Biological Journal of the Linnean Society. 138: 103–120. doi:10.1093/biolinnean/blac131. ISSN   0024-4066.
  9. Gallina, Pablo A.; Apesteguía, Sebastián; Canale, Juan I.; Haluza, Alejandro (2019-02-04). "A new long-spined dinosaur from Patagonia sheds light on sauropod defense system". Scientific Reports. 9 (1): 1392. doi: 10.1038/s41598-018-37943-3 . ISSN   2045-2322. PMC   6362061 . PMID   30718633. S2CID   59603627.
  10. Whitlock, John A.; Wilson Mantilla, Jeffrey A. (2020-12-23). "The Late Jurassic sauropod dinosaur 'Morosaurus' agilis Marsh, 1889 reexamined and reinterpreted as a dicraeosaurid". Journal of Vertebrate Paleontology. 40 (6): e1780600. doi:10.1080/02724634.2020.1780600. eISSN   1937-2809. ISSN   0272-4634. S2CID   234424022.
  11. Gnaedinger, Silvia; Coria, Rodolfo A.; Koppelhus, Eva; Casadío, Silvio; Tunik, Maisa; Currie, Philip (2017). "First Lower Cretaceous record of Podocarpaceae wood associated with dinosaur remains from Patagonia, Neuquén Province, Argentina". Cretaceous Research. 78: 228–239. doi:10.1016/j.cretres.2017.06.014. ISSN   0195-6671.