Minimocursor Temporal range: Late Jurassic, | |
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Skeletal diagrams showing the holotype specimen (above) and the holotype with assigned elements (below) | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Neornithischia |
Genus: | † Minimocursor Manitkoon et al., 2023 |
Type species | |
†Minimocursor phunoiensis Manitkoon et al., 2023 |
Minimocursor (meaning "smallest runner") is a genus of basal neornithischian dinosaur from the Late Jurassic Phu Kradung Formation of Thailand. The type species is Minimocursor phunoiensis. [1]
The holotype specimen, PRC 150, was excavated in 2012 and prepared for the next five years. It consists of a postcranial specimen that is more than 50% complete. Other referred specimens include an isolated dentary briefly described in 2014 and pes material. [2] Several more specimens remain unprepared as of 2023. [1]
These bones were considered to represent a new genus and species, Minimocursor phunoiensis, in 2023. The generic name, "Minimocursor", combines the Latin words "minimus", meaning "the smallest", in reference to the holotype's small size, and "cursor", meaning "runner". The specific name, "phunoiensis", refers to the excavation site, Phu Noi. [1]
The not-fully-grown holotype has been estimated as 0.6 metres (2.0 ft) long, similar to the size of Agilisaurus . Larger remains hint that the fully-grown animal would have been 2 metres (6.6 ft) long. [1]
Manitkoon et al. (2023) added Minimocursor to a phylogenetic analysis, adding the holotype, pes, and dentary as separate operational taxonomic units (OTUs). All three claded together at the base of the Neornithischia, outside Thescelosauridae and Cerapoda, making it the first basal neornithischian known from Southeast Asia. Their cladogram is shown below: [1]
The Phu Kradung Formation preserves a diverse assemblage of animals. Minimocursor would have lived alongside several fish and turtles, an indeterminate pterosaur, an indeterminate stegosaur, an indeterminate metriacanthosaurid, an indeterminate mamenchisaurid, and the thalattosuchian Indosinosuchus . [1] [3] [4]
Siamotyrannus is a genus of theropod dinosaur from the early Cretaceous of Thailand.
Siamosaurus is a genus of spinosaurid dinosaur that lived in what is now known as China and Thailand during the Early Cretaceous period and is the first reported spinosaurid from Asia. It is confidently known only from tooth fossils; the first were found in the Sao Khua Formation, with more teeth later recovered from the younger Khok Kruat Formation. The only species Siamosaurus suteethorni, whose name honours Thai palaeontologist Varavudh Suteethorn, was formally described in 1986. In 2009, four teeth from China previously attributed to a pliosaur—under the species "Sinopliosaurus" fusuiensis—were identified as those of a spinosaurid, possibly Siamosaurus. It is yet to be determined if two partial spinosaurid skeletons from Thailand and an isolated tooth from Japan also belong to Siamosaurus.
Kinnareemimus is an extinct genus of ornithomimosaurian theropod dinosaur that was discovered in the Early Cretaceous Sao Khua Formation in what is now Thailand. The genus contains only the type species, K. khonkaenensis. The specific epithet is after Khon Kaen Province, which is in northeastern Thailand, where the remains of the animal were discovered.
Phuwiangosaurus is a genus of titanosaur dinosaur from the Early Cretaceous (Valanginian-Hauterivian) Sao Khua Formation of Thailand. The type species, P. sirindhornae, was described by Martin, Buffetaut, and Suteethorn in a 1993 press release and was formally named in 1994. The species was named to honor Princess Maha Chakri Sirindhorn of Thailand, who was interested in the geology and palaeontology of Thailand, while the genus was named after the Phu Wiang area, where the fossil was discovered.
Ferganoceratodus is a genus of prehistoric lungfish known from the Mesozoic of Asia. Based on morphological evidence, it has either been recovered as a basal member of the Ceratodontiformes or to be the sister group of the Neoceratodontidae.
The Sao Khua Formation is a middle member of the Khorat Group. It consists of an alteration of pale red to yellowish-gray, fine to medium-grained sandstone and grayish-reddish brown siltstone and clay. Rare pale red to light gray conglomerates, containing carbonate pebbles, are also characteristic of this formation. This geological formation in Thailand dates to the Early Cretaceous age, specifically the Valanginian through Hauterivian stages.
Mamenchisauridae is a family of sauropod dinosaurs belonging to Eusauropoda known from the Jurassic and Early Cretaceous of Asia and Africa. Some members of the group reached gigantic sizes, amongst the largest of all sauropods.
Basilochelys is an extinct genus of land turtle which existed during the early Cretaceous period (Berriasian). Containing the sole species Basilochelys macrobios, its fossils have been found in the Phu Kradung Formation of Northeast Thailand. It is considered to be the most basal member of the group Trionychoidae.
The Early Cretaceous Phu Kradung Formation is the lowest member of the Mesozoic Khorat Group which outcrops on the Khorat Plateau in Isan, Thailand. This geological formation consists of micaceous, brown to reddish-brown siltstone beds with minor brown and grey shale and sandstone beds. Occasional lime-noduled conglomerate occurs.
Sunosuchus is an extinct genus of goniopholidid mesoeucrocodylian. Fossils are known from China, Kyrgyzstan, and Thailand and are Jurassic in age, although some may be Early Cretaceous. Four species are currently assigned to the genus: the type species S. miaoi and the species S. junggarensis, S. shartegensis, and S. shunanensis. All species are from China. Goniopholis phuwiangensis, also from Thailand, was reassigned to Sunosuchus by Andrade et al. (2011). The material from Kyrgyzstan has not been assigned to any species.
Siamodon is an extinct genus of iguanodontian ornithopod dinosaur from Early Cretaceous deposits of northeastern Thailand.
The Khok Kruat Formation is a rock formation found in northeastern Thailand. It is the uppermost formation of the Khorat Group. It is dated to the Aptian stage of the Early Cretaceous period, and is notable for its fossils of dinosaurs. It is equivalent to the Gres superieurs Formation of Laos. The group is a fluvial formation consisting primarily of red siltstones and sandstones.
Ichthyovenator is a genus of spinosaurid dinosaur that lived in what is now Laos, sometime between 120 and 113 million years ago, during the Aptian stage of the Early Cretaceous period. It is known from fossils collected from the Grès supérieurs Formation of the Savannakhet Basin, the first of which were found in 2010, consisting of a partial skeleton without the skull or limbs. This specimen became the holotype of the new genus and species Ichthyovenator laosensis, and was described by palaeontologist Ronan Allain and colleagues in 2012. The generic name, meaning "fish hunter", refers to its assumed piscivorous lifestyle, while the specific name alludes to the country of Laos. In 2014, it was announced that more remains from the dig site had been recovered; these fossils included teeth, more vertebrae (backbones) and a pubic bone from the same individual.
Chalawan is an extinct genus of pholidosaurid mesoeucrocodylian known from the Late Jurassic or Early Cretaceous Phu Kradung Formation of Nong Bua Lamphu Province, northeastern Thailand. It contains a single species, Chalawan thailandicus, with Chalawan shartegensis as a possible second species.
Xinjiangchelyidae is an extinct family of turtles known from the Lower Jurassic to the Middle Cretaceous of Asia and western Europe. They have generally been interpreted as either being basal cryptodires or placed outside of crown Testudines.
Varavudh Suteethorn, or Warawut Suteethorn is a Thai palaeontologist and geologist. He is the current director of the Palaeontological Research and Education Centre, Mahasarakham University. He is best known for his work on vertebrate paleontology in northeastern Thailand, having contributed to the discovery of many fossil taxa and dig sites in the Khorat Plateau, as a part of a long-standing collaboration between Thai and French scientists.
Anatolemys is an extinct turtle genus in the family Macrobaenidae. Two species are known, both of which lived in the Late Cretaceous. Fossils were discovered in the Yalovach Formation of Tajikistan, the Kulbikin Member and Khodzhakul and Bissekty Formations of Uzbekistan and the Bostobe Formation of Kazakhstan. With 70 cm (2.3 ft) in carapace length, Anatolemys maximus was one of the three largest macrobaenids along with Early Cretaceous Yakemys multiporcata and Paleocene Judithemys backmani.
Phuwiangvenator is an extinct genus of megaraptoran theropod that lived during the Early Cretaceous period in what is now Thailand. It contains only the type species, P. yaemniyomi. The generic name of Phuwiangvenator comes from the Phu Wiang mountains, where the holotype was discovered, and the Latin word "venator" meaning hunter. The specific name, "yaemniyomi", is in honor of Sudham Yaemniyom, who was a historical paleontologist from Thailand and the first person to discover fossils there.
Indosinosuchus is a genus of teleosaurid neosuchian that lived during the Late Jurassic or Early Cretaceous in what is now Thailand. It contains two species, the type species I. potamosiamensis and I. kalasinensis, both recovered from the lower Phu Kradung Formation. It is unique among teleosauroids as it is the only named genus known from a freshwater environment, while most other members of the group are marine. Indosinosuchus is placed in the family Teleosauridae, but has a relatively robust skull that bears resemblance to members of the Machimosauridae. Biomechanical analysis of its mandible and teeth suggest that it would have had a substantial bite force comparable to animals like Lemmysuchus. The two Indosinosuchus species however differ in the speed at which they could open and close their jaws, impacting their respective ecology and possibly explaining how they coexisted in the same environment. All known specimens of this genus were recovered from a single locality, which has been interpreted as a mass death site, possibly caused by a drought or flash flood. The precise age of Indosinosuchus is unclear, as the vertebrate fossils of the Phu Kradung Formation support a Late Jurassic age, while palynological data suggests an Early Cretaceous (Berriasian) age.
Yakemys is an extinct genus of macrobaenid turtles from the Late Jurassic-Early Cretaceous (Tithonian-Valanginian?) lower Phu Kradung Formation of Thailand. It is monotypic, containing a single species, Yakemys multiporcata.