Deccansaurus

Last updated

Deccansaurus
Temporal range: Maastrichtian or Danian, 66  Ma
O
S
D
C
P
T
J
K
Pg
N
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Infraorder: Scincomorpha
Clade: Cordyliformes
Genus: Deccansaurus
Yadav et al, 2023
Species:
D. paleoindicus
Binomial name
Deccansaurus paleoindicus
Yadav, Bajpai, Maurya & Čerňanský, 2023

Deccansaurus ("Deccan Traps lizard") is an extinct genus of scincomorphan (potentially a stem-cordyliform) lizard from the latest Cretaceous or earliest Paleocene of India. A single species is known, D. paleoindicus, represented by jaws and some osteoderm fragments from the Intertrappean Beds of the Dhar district in Madhya Pradesh. [1]

The morphology of Deccansaurus suggests that it was a distant relative of modern skinks. In addition, it shares close similarities with members of the clade Cordyliformes (represented in the modern day by Cordylidae and Gerrhosauridae from mainland Africa and Madagascar), which would potentially mark the first occurrence of this group from the Indian subcontinent, which at the time was an island continent that had split from Madagascar several million years prior. An extinct cordyliform, Konkasaurus , is also known from the latest Cretaceous of Madagascar and shares many features with Deccansaurus, indicating close similarities between the faunas of India and Madagascar at the time and their shared ancestries. [1] [2] [3]

Related Research Articles

<span class="mw-page-title-main">Multituberculata</span> Extinct order of mammals

Multituberculata is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, and reached a peak diversity during the Late Cretaceous and Paleocene. They eventually declined from the mid-Paleocene onwards, disappearing from the known fossil record in the late Eocene. They are the most diverse order of Mesozoic mammals with more than 200 species known, ranging from mouse-sized to beaver-sized. These species occupied a diversity of ecological niches, ranging from burrow-dwelling to squirrel-like arborealism to jerboa-like hoppers. Multituberculates are usually placed as crown mammals outside either of the two main groups of living mammals—Theria, including placentals and marsupials, and Monotremata—but usually as closer to Theria than to monotremes. They are considered to be closely related to Euharamiyida and Gondwanatheria as part of Allotheria.

<span class="mw-page-title-main">Afrotheria</span> Clade of mammals containing elephants and elephant shrews

Afrotheria is a superorder of mammals, the living members of which belong to groups that are either currently living in Africa or of African origin: golden moles, elephant shrews, otter shrews, tenrecs, aardvarks, hyraxes, elephants, sea cows, and several extinct clades. Most groups of afrotheres share little or no superficial resemblance, and their similarities have only become known in recent times because of genetics and molecular studies. Many afrothere groups are found mostly or exclusively in Africa, reflecting the fact that Africa was an island continent from the Cretaceous until the early Miocene around 20 million years ago, when Afro-Arabia collided with Eurasia.

<span class="mw-page-title-main">Rhynchocephalia</span> Order of reptiles

Rhynchocephalia is an order of lizard-like reptiles that includes only one living species, the tuatara of New Zealand. Despite its current lack of diversity, during the Mesozoic rhynchocephalians were a speciose group with high morphological and ecological diversity. The oldest record of the group is dated to the Middle Triassic around 238 to 240 million years ago, and they had achieved a worldwide distribution by the Early Jurassic. Most rhynchocephalians belong to the group Sphenodontia ('wedge-teeth'). Their closest living relatives are lizards and snakes in the order Squamata, with the two orders being grouped together in the superorder Lepidosauria.

<span class="mw-page-title-main">Choristodera</span> Extinct order of reptiles

Choristodera is an extinct order of semiaquatic diapsid reptiles that ranged from the Middle Jurassic, or possibly Triassic, to the Miocene. Choristoderes are morphologically diverse, with the best known members being the crocodile-like neochoristoderes such as Champsosaurus. Other choristoderans had lizard-like or long necked morphologies. Choristoderes appear to have been confined to the Northern Hemisphere, having been found in North America, Asia, and Europe, and possibly also North Africa. Choristoderes are generally thought to be derived neodiapsids that are close relatives or members of Sauria.

<span class="mw-page-title-main">Cimolesta</span> Extinct order of mammals

Cimolesta is an extinct order of non-placental eutherian mammals. Cimolestans had a wide variety of body shapes, dentition and lifestyles, though the majority of them were small to medium-sized general mammals that bore superficial resemblances to rodents, lagomorphs, mustelids, and marsupials.

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

Abelisauridae is a family of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are found on the modern continents of Africa and South America, as well as on the Indian subcontinent and the island of Madagascar. Isolated teeth were found in the Late Jurassic of Portugal, and the Late Cretaceous genera Tarascosaurus and Arcovenator have been described in France. Abelisaurids first appear in the fossil record of the early middle Jurassic period, and at least three genera survived until the end of the Mesozoic era 66 million years ago.

<span class="mw-page-title-main">Ichthyornithes</span> Extinct clade of dinosaurs

Ichthyornithes is an extinct group of toothed avialans very closely related to the common ancestor of all modern birds. They are known from fossil remains found throughout the late Cretaceous period of North America, though only two genera, Ichthyornis and Janavis, are represented by complete enough fossils to have been named. Ichthyornitheans became extinct at the Cretaceous–Paleogene boundary, along with enantiornitheans, all other non-avian dinosaurs, and many other animal and plant groups.

<span class="mw-page-title-main">Scolecophidia</span> Infraorder of snakes

The Scolecophidia, commonly known as blind snakes or thread snakes, are an infraorder of snakes. They range in length from 10 to 100 centimetres. All are fossorial. Five families and 39 genera are recognized. The Scolecophidia infraorder is most likely paraphyletic.

<i>Beelzebufo</i> Extinct genus of amphibians

Beelzebufo is a particularly large species of prehistoric frog described in 2008. Common names assigned by the popular media include devil frog, devil toad, and the frog from hell.

<i>Titanoboa</i> Extinct genus of snakes

Titanoboa is an extinct genus of giant boid snake that lived during the middle and late Paleocene. Titanoboa was first discovered in the early 2000s by the Smithsonian Tropical Research Institute who, along with students from the University of Florida, recovered 186 fossils of Titanoboa from La Guajira in northeastern Colombia. It was named and described in 2009 as Titanoboa cerrejonensis, the largest snake ever found. It was originally known only from thoracic vertebrae and ribs, but later expeditions collected parts of the skull and teeth. Titanoboa is in the subfamily Boinae, being most closely related to other extant boines from Madagascar and the Pacific.

<span class="mw-page-title-main">Evolution of lemurs</span> History of primate evolution on Madagascar

Lemurs, primates belonging to the suborder Strepsirrhini which branched off from other primates less than 63 million years ago, evolved on the island of Madagascar, for at least 40 million years. They share some traits with the most basal primates, and thus are often confused as being ancestral to modern monkeys, apes, and humans. Instead, they merely resemble ancestral primates.

UA 8699 is a fossil mammalian tooth from the Cretaceous of Madagascar. A broken lower molar about 3.5 mm (0.14 in) long, it is from the Maastrichtian of the Maevarano Formation in northwestern Madagascar. Details of its crown morphology indicate that it is a boreosphenidan, a member of the group that includes living marsupials and placental mammals. David W. Krause, who first described the tooth in 2001, interpreted it as a marsupial on the basis of five shared characters, but in 2003 Averianov and others noted that all those are shared by zhelestid placentals and favored a close relationship between UA 8699 and the Spanish zhelestid Lainodon. Krause used the tooth as evidence that marsupials were present on the southern continents (Gondwana) as early as the late Cretaceous and Averianov and colleagues proposed that the tooth represented another example of faunal exchange between Africa and Europe at the time.

Several mammals are known from the Mesozoic of Madagascar. The Bathonian Ambondro, known from a piece of jaw with three teeth, is the earliest known mammal with molars showing the modern, tribosphenic pattern that is characteristic of marsupial and placental mammals. Interpretations of its affinities have differed; one proposal places it in a group known as Australosphenida with other Mesozoic tribosphenic mammals from the southern continents (Gondwana) as well as the monotremes, while others favor closer affinities with northern (Laurasian) tribosphenic mammals or specifically with placentals. At least five species are known from the Maastrichtian, including a yet undescribed species known from a nearly complete skeleton that may represent a completely new group of mammals. The gondwanathere Lavanify, known from two teeth, is most closely related to other gondwanatheres found in India and Argentina. Two other teeth may represent another gondwanathere or a different kind of mammal. One molar fragment is one of the few known remains of a multituberculate mammal from Gondwana and another has been interpreted as either a marsupial or a placental.

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

Gannansaurus is an extinct genus of somphospondylan sauropod dinosaur known from the latest Cretaceous Nanxiong Formation of Ganzhou Basin, Jiangxi Province of southern China. It is known from specimen GMNH F10001 which consists of a single, nearly complete dorsal vertebra and a mid-caudal vertebra. Gannansaurus was first named by Lü Junchang, Yi Laiping, Zhong Hui and Wei Xuefang in 2013 and the type species is Gannansaurus sinensis. Gannansaurus shares some characters with Euhelopus, indicating that it is more closely related to it rather than to other titanosauriforms.

<span class="mw-page-title-main">Lacertoidea</span> Superfamily of lizards

The Lacertoidea is a group of squamate reptiles that includes the Lacertidae, Teiidae, Gymnophthalmidae, and Amphisbaenia. The finding from molecular phylogenetic studies that the burrowing Amphisbaenia were nested in a clade with the lizard forms led Vidal & Hedges (2005) to propose a new name for the group based on shared morphogical characters, Laterata, "referring to the presence of tile-like scales that form the rings in Amphisbaenia, and are also present ventrally in Lacertiformata and Teiformata".

<span class="mw-page-title-main">Majungasaurinae</span> Extinct subfamily of reptiles

Majungasaurinae is a subfamily of large carnivorous theropods from the Upper Cretaceous, found in Madagascar, India, and France. It is a subgroup within the theropod family Abelisauridae, a Gondwanan clade known for their thick and often horned skulls and vestigial arms. The two subfamilies of Abelisauridae are Carnotaurinae, best known from the South American Carnotaurus, and Majungasaurinae, consisting of Madagascar’s Majungasaurus and its closest relatives. Their ancestors emerged in the Middle Jurassic, and the clade lasted until the Upper Cretaceous.

<i>Ocepeia</i> Extinct Afrotherian mammal

Ocepeia is an extinct genus of afrotherian mammal that lived in present-day Morocco during the middle Paleocene epoch, approximately 60 million years ago. First named and described in 2001, the type species is O. daouiensis from the Selandian stage of Morocco's Ouled Abdoun Basin. A second, larger species, O. grandis, is known from the Thanetian, a slightly younger stage in the same area. In life, the two species are estimated to have weighed about 3.5 kg (7.7 lb) and 10 kg (22 lb), respectively, and are believed to have been specialized leaf-eaters. The fossil skulls of Ocepeia are the oldest known afrotherian skulls, and the best-known of any Paleocene mammal in Africa.

Australornis is a genus of extinct seabird discovered in New Zealand. It lived in the Paleocene epoch, 60.5 to 61.6 million years ago (Ma). The type species name originates from australis, Latin for "southern", and ornis, the Greek word for "bird", and lovei commemorates Leigh Love, an amateur paleontologist who discovered it.

<span class="mw-page-title-main">Insular India</span> Isolated land mass which became the Indian subcontinent

Insular India was an isolated landmass which became the Indian subcontinent. Across the latter stages of the Cretaceous and most of the Paleocene, following the breakup of Gondwana, the Indian subcontinent remained an isolated landmass as the Indian Plate drifted across the Tethys Ocean, forming the Indian Ocean. The process of India's separation from Madagascar first began 88 million years ago, but complete isolation only occurred towards the end of the Maastrichtian, a process that has been suggested to be the creation of the Deccan Traps. Soon after, the land mass moved northward rather quickly, until contact with Asia was established 55 million years ago. Even then, both landmasses did not become fully united until around 35 million years ago, and periods of isolation occurred as recently as 24 million years ago.

<i>Peradectes</i>

Peradectes is an extinct genus of small metatherian mammals known from the latest Cretaceous to Eocene of North and South America and Europe. The first discovered fossil of P. elegans, was one of 15 Peradectes specimens described in 1921 from the Mason pocket fossil beds in Colorado. The monophyly of the genus has been questioned.

References

  1. 1 2 Yadav, Ravi; Bajpai, Sunil; Maurya, A. S.; Čerňanský, Andrej (2023-10-01). "The first potential cordyliform (Squamata, Scincoidea) from India (uppermost Cretaceous – lowermost Paleocene): An African lizard clade brings possible implications for Indo-Madagascar biogeographic links". Cretaceous Research. 150: 105606. doi:10.1016/j.cretres.2023.105606. ISSN   0195-6671.
  2. "Presence of African reptiles in India confirms that these territories once belonged together". uniba.sk. Retrieved 2023-12-14.
  3. a.s, Petit Press (2023-07-15). "Scientists find fossil lizard from the dinosaur era in India". spectator.sme.sk. Retrieved 2023-12-14.