Bissektipelta

Last updated

Bissektipelta
Temporal range: Turonian
~92–90  Ma
Ꞓ
O
S
D
C
P
T
J
K
Pg
N
↓
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade:† Ornithischia
Clade:† Thyreophora
Clade:† Ankylosauria
Family:† Ankylosauridae
Subfamily:† Ankylosaurinae
Genus:† Bissektipelta
Parish & Barrett, 2004
Type species
†Bissektipelta archibaldi
Parish & Barrett, 2004
Synonyms

Bissektipelta (meaning "Bissekty shield") is a genus of ankylosaurine thyreophoran dinosaurs that lived in Asia during the Late Cretaceous in what is now the Bissekty Formation of Uzbekistan. Bissektipelta is a monospecific genus, containing only the type species B. archibaldi.

Contents

History of discovery

In September 1998, the joint Uzbek-Russian-British-American-Project excavated the braincase of an ankylosaur. In 2002, Alexandr Averianov, based on this find, named a second species of the genus Amtosaurus : Amtosaurus archibaldi. The specific name honours James David Archibald, leading the URBAC (Uzbekistan, Russia, Britain, America, & Canada) project that performed the excavation. [1]

The holotype specimen, ZIN PH 1/6, was collected from the Bissekty Formation, dating from the late Turonian-Coniacian, of Dzharakuduk. It consists of a well-preserved, fully ossified braincase with a partial skull roof, along with isolated teeth and osteoderms. [1]

In 2004, Jolyon Parish and Paul Barrett concluded that the type species of Amtosaurus, Amtosaurus magnus, was a nomen dubium , a dubious name. This implied that no other species could be validly referred to the genus Amtosaurus. A. archibaldi should be reassigned to a new taxon. They renamed the genus as Bissektipelta with the generic name combining a reference to the geological formation with a Latin pelta (meaning small shield), which is derived from the Greek peltè (meaning shield). The type species is the original A. archibaldi but the new combination is Bissektipelta archibaldi. [2]

Two additional specimens were referred to by Kuzmin and colleagues in 2020. These consist of ZIN PH 281/16, a smaller but well-preserved partial braincase with open sutures between some bones and ZIN PH 2329/16, another braincase similar in size to the holotype that is slightly damaged and mixed up within the sediment layer. [3]

Description

Parish & Barrett indicated some distinguishing traits of Bissektipelta. One of these is an autapomorphy, a unique derived character. On the top skull roof grooves are present, together forming a truncated "Y" and separating three polygonal areas of flat remodelled bone tissue. [2] These grooves reflected the position of skull osteoderms. Averianov had in 2002 proposed three traits in which A. archibaldi differed from A. magnus. Its braincase has three exits for the Nervus hypoglossus (cranial nerve XII) instead of two. It also has a more limited angle of 90° between the ventral surfaces of the basioccipital and the basisphenoid, and more caudally, to the rear, situated basipterygoid processes. [1] In 2004, these were no longer considered unique traits but the triple exits were seen as rare. [2]

Classification

When described in 2002, Averianov placed A. archibaldi in the Ankylosauridae. [1] Parish & Barrett thought such precision was unwarranted and placed the newly Bissektipelta in a more general Ankylosauria. [2] However, Victoria M. Arbour and Philip J. Currie affirmed the position within the Ankylosauridae. [4] [5] Based on numerous cranial traits, Kuzmin and colleagues have placed Bissektipelta within the advanced Ankylosaurinae in a basal position and confirmed its valid taxonomic status. [3]

Paleobiology

In 2019, Alifanov and Saveliev redescribed the braincase noting that Bissektipelta had a well-developed olfaction, poor hearing and eyesight, good taste sensitivity, omnivorous diet and the unusual ability for filter-feeding. Also, the brain structure of Bissektipelta is rather primitive compared with other ankylosaur species. [6] In 2020, Ivan Kuzmin and colleagues described and examined the braincase specimens of Bissektipelta in extensive detail. They performed a 3D reconstruction of the endocast of the brain cavity using CT scans and they revealed that a considerable part of the brain of Bissektipelta was occupied by olfactory bulbs, confirming that Bissektipelta had an extremely developed sense of smell. The numerous small vascular canals around the skull roof, the lateral wall of the brain case and cranial vessels form a complex network around the brain which allowed the redistribution of the blood flow and physiological mechanisms for heat exchange in order to cool-down the brain and maintain optimal temperatures. In addition, the length of the cochlear ducts in the inner ear suggests that Bissektipelta, and many other ankylosaurs, were adapted for low frequency-hearing within 100 Hz and 3000 Hz. The elongated cochlear ducts in the more advanced ankylosaurines seem to indicate that these traits were adapted for enhanced hearing at lower frequencies. [3]

See also

Related Research Articles

<span class="mw-page-title-main">Ankylosauria</span> Extinct order of dinosaurs

Ankylosauria is a group of herbivorous dinosaurs of the clade Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are known to have first appeared in the Middle Jurassic, and persisted until the end of the Cretaceous Period. The two main families of Ankylosaurs, Nodosauridae and Ankylosauridae are primarily known from the Northern Hemisphere, but the more basal Parankylosauria are known from southern Gondwana during the Cretaceous.

<i>Ankylosaurus</i> Ankylosaurid dinosaur genus from the Late Cretaceous Period

Ankylosaurus is a genus of armored dinosaur. Its fossils have been found in geological formations dating to the very end of the Cretaceous Period, about 68–66 million years ago, in western North America, making it among the last of the non-avian dinosaurs. It was named by Barnum Brown in 1908; it is monotypic, containing only A. magniventris. The generic name means "fused" or "bent lizard", and the specific name means "great belly". A handful of specimens have been excavated to date, but a complete skeleton has not been discovered. Though other members of Ankylosauria are represented by more extensive fossil material, Ankylosaurus is often considered the archetypal member of its group, despite having some unusual features.

<i>Pinacosaurus</i> Genus of ankylosaurid dinosaur from Late Cretaceous

Pinacosaurus is a genus of ankylosaurid thyreophoran dinosaur that lived in Asia during the Late Cretaceous, mainly in Mongolia and China.

<i>Gastonia</i> (dinosaur) Ankylosaurian dinosaur genus from the Early Cretaceous period

Gastonia is a genus of herbivorous ankylosaurian dinosaur from the Early Cretaceous of North America, around 139 to 134.6 million years ago. It is often considered a nodosaurid closely related to Polacanthus. Gastonia has a sacral shield and large shoulder spikes.

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

Ankylosauridae is a family of armored dinosaurs within Ankylosauria, and is the sister group to Nodosauridae. The oldest known Ankylosaurids date to around 122 million years ago and went extinct 66 million years ago during the Cretaceous–Paleogene extinction event. These animals were mainly herbivorous and were obligate quadrupeds, with leaf-shaped teeth and robust, scute-covered bodies. Ankylosaurids possess a distinctly domed and short snout, wedge-shaped osteoderms on their skull, scutes along their torso, and a tail club.

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

Amtosaurus is a genus of ornithischian dinosaur based on a fragmentary skull collected from the Upper Cretaceous Bayan Shireh Formation of Mongolia and originally believed to represent an ankylosaurid. Hadrosaurid affinities have also been suggested. However, per Parish and Barrett, this specimen is too fragmentary to be reliably classified beyond an indeterminate ornithischian. A second species assigned to the genus, A. archibaldi, has become the basis of a valid ankylosaurid taxon, Bissektipelta.

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

Anodontosaurus is an extinct genus of ankylosaurid dinosaurs within the subfamily Ankylosaurinae. It is known from the entire span of the Late Cretaceous Horseshoe Canyon Formation of southern Alberta, Canada, and is also known from the Dinosaur Park Formation. It contains two species, A. lambei and A. inceptus.

Shamosaurus is an extinct genus of herbivorous basal ankylosaurid ankylosaur from Early Cretaceous deposits of Höövör, Mongolia.

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

Cedarpelta is an extinct genus of basal ankylosaurid dinosaur from Utah that lived during the Late Cretaceous period in what is now the Mussentuchit Member of the Cedar Mountain Formation. The type and only species, Cedarpelta bilbeyhallorum, is known from multiple specimens including partial skulls and postcranial material. It was named in 2001 by Kenneth Carpenter, James Kirkland, Don Burge, and John Bird. Cedarpelta has an estimated length of 7 metres and weight of 5 tonnes (11,023 lbs). The skull of Cedarpelta lacks extensive cranial ornamentation and is one of the only known ankylosaurs with individual skull bones that are not completely fused together.

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

Tianzhenosaurus is a monospecific genus of ankylosaurid dinosaur from the Shanxi Province that lived during the Late Cretaceous in what is now the Huiquanpu Formation. Tianzhenosaurus may represent a junior synonym of Saichania, an ankylosaurine known from the Barun Goyot and Nemegt Formation.

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

Gobisaurus is an extinct genus of herbivorous basal ankylosaurid ankylosaur from the Upper Cretaceous of China. The genus is monotypic, containing only the species Gobisaurus domoculus.

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

Tarchia is a genus of herbivorous ankylosaurid dinosaur from the late Cretaceous of Mongolia.

<i>Talarurus</i> Ankylosaurid dinosaur genus from the Late Cretaceous

Talarurus is a genus of ankylosaurid dinosaur that lived in Asia during the Late Cretaceous period, about 96 million to 89 million years ago. The first remains of Talarurus were discovered in 1948 and later described by the Russian paleontologist Evgeny Maleev with the type species T. plicatospineus. It is known from multiple yet sparse specimens, making it one of the most well known ankylosaurines, along with Pinacosaurus. Elements from the specimens consists of various bones from the body; five skulls have been discovered and assigned to the genus, although the first two were very fragmented.

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

Nodocephalosaurus is a monospecific genus of ankylosaurid dinosaur from New Mexico that lived during the Late Cretaceous in what is now the De-na-zin member of the Kirtland Formation. The type and only species, Nodocephalosaurus kirtlandensis, is known only from a partial skull. It was named in 1999 by Robert M. Sullivan. Nodocephalosaurus has an estimated length of 4.5 metres and weight of 1.5 tonnes. It is closely related and shares similar cranial anatomy to Akainacephalus.

Heishansaurus, meaning "Heishan lizard" after the area in China where it was discovered, is the name given to a dubious genus of herbivorous ornithischian dinosaur, probably belonging to the Ankylosauridae.

Shanxia is a monospecific genus of ankylosaurid dinosaur from the Shanxi Province that lived during the Late Cretaceous in what is now the Huiquanpu Formation. Shanxia may possibly represent a junior synonym of Tianzhenosaurus, an ankylosaurine also known from the Huiquanpu Formation of China.

<i>Ziapelta</i> Genus of ankylosaurid dinosaur from the Late Cretaceous period

Ziapelta is an extinct genus of ankylosaurid. Its fossils have been found in the Hunter Wash and De-na-zin members of the Kirtland Formation of Upper Cretaceous (Campanian) New Mexico. It was named in 2014, in a research paper led by ankylosaur researcher Victoria Arbour. There is a single species in the genus, Ziapelta sanjuanensis. The genus is named after the Zia sun symbol, a stylized sun with four groups of rays, having religious significance to the Zia people of New Mexico, and the iconic symbol on the state flag of New Mexico, and pelta (Latin), a small shield, in reference to the osteoderms found on all ankylosaurids. The specific name is in reference to San Juan County and the San Juan basin, where the fossils were found. Multiple specimens have been described to date, though the fossils are mostly from the front part of the animal. Its closest relative appears to be either Scolosaurus or Nodocephalosaurus, depending on what cladistic model is used.

<span class="mw-page-title-main">Timeline of ankylosaur research</span>

This timeline of ankylosaur research is a chronological listing of events in the history of paleontology focused on the ankylosaurs, quadrupedal herbivorous dinosaurs who were protected by a covering bony plates and spikes and sometimes by a clubbed tail. Although formally trained scientists did not begin documenting ankylosaur fossils until the early 19th century, Native Americans had a long history of contact with these remains, which were generally interpreted through a mythological lens. The Delaware people have stories about smoking the bones of ancient monsters in a magic ritual to have wishes granted and ankylosaur fossils are among the local fossils that may have been used like this. The Native Americans of the modern southwestern United States tell stories about an armored monster named Yeitso that may have been influenced by local ankylosaur fossils. Likewise, ankylosaur remains are among the dinosaur bones found along the Red Deer River of Alberta, Canada where the Piegan people believe that the Grandfather of the Buffalo once lived.

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

Kunbarrasaurus is an extinct genus of small ankylosaurian dinosaur from the Cretaceous of Australia. The genus conatins a single species, K. ieversi.

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

Timurlengia is an extinct genus of tyrannosauroid theropod dinosaur found in Uzbekistan, in the Bissekty Formation in the Kyzylkum Desert, hailing from the Turonian age of the early Late Cretaceous. The type species is Timurlengia euotica.

References

  1. 1 2 3 4 Averianov, A. O. (2002). "An ankylosaurid (Ornithischia: Ankylosauria) braincase from the Upper Cretaceous Bissekty Formation of Uzbekistan" (PDF). Bulletin of the Royal Belgian Institute of Natural Sciences - Earth Sciences. 72: 97–110. ISSN   0374-6291.
  2. 1 2 3 4 Parish, J. C.; Barrett, P. M. (2004). "A reappraisal of the ornithischian dinosaur Amtosaurus magnus Kurzanov and Tumanova 1978, with comments on the status of A. archibaldi Averianov 2002". Canadian Journal of Earth Sciences. 41 (3): 299–306. Bibcode:2004CaJES..41..299P. doi:10.1139/e03-101.
  3. 1 2 3 Kuzmin, I.; Petrov, I.; Averianov, A. O.; Boitsova, E.; Skutschas, P.; Sues, H.-D. (2020). "The braincase of Bissektipelta archibaldi — new insights into endocranial osteology, vasculature, and paleoneurobiology of ankylosaurian dinosaurs". Biological Communications. 65 (2): 85−156. doi: 10.21638/spbu03.2020.201 . hdl: 11701/19215 .
  4. ↑ Arbour, V. M. (2014). Systematics, evolution, and biogeography of the ankylosaurid dinosaurs (PDF) (PhD Thesis). University of Alberta. p. 265.
  5. ↑ Arbour, V. M.; Currie, P. J. (2015). "Systematics, phylogeny and palaeobiogeography of the ankylosaurid dinosaurs". Journal of Systematic Palaeontology. 14 (5): 385–444. Bibcode:2016JSPal..14..385A. doi:10.1080/14772019.2015.1059985. S2CID   214625754.
  6. ↑ Alifanov, V. R.; Saveliev, S. V. (2019). "The Brain Morphology and Neurobiology in Armored Dinosaur Bissekipelta archibaldi (Ankylosauridae) from the Late Cretaceous of Uzbekistan". Paleontological Journal. 53 (3): 315−321. Bibcode:2019PalJ...53..315A. doi:10.1134/S003103011903002X. ISSN   0031-0301. S2CID   195299630.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.