Bissektipelta

Source: Wikipedia, the free encyclopedia.

Bissektipelta
Temporal range:
Ma
↓
Scientific classification Edit this classification
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
  • Amtosaurus archibaldi Averianov, 2002
  • Amtosaurus magnus
    ? Kurzanov & Tumanova, 1978

Bissektipelta (meaning "

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.

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

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

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

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

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

References

  1. ^
    ISSN 0374-6291
    .
  2. ^
    doi:10.1139/e03-101
    .
  3. ^
    hdl:11701/19215
    .
  4. ^ Arbour, V. M. (2014). "Systematics, evolution, and biogeography of the ankylosaurid dinosaurs" (PDF). Ph.D Thesis: 265.
  5. S2CID 214625754
    .
  6. S2CID 195299630
    .
Retrieved from "https://en.wikipedia.org/w/index.php?title=Bissektipelta&oldid=1201637111"