Wakinosaurus

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Wakinosaurus
Temporal range: Early Cretaceous, 136–125  Ma
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Genus: Wakinosaurus
Okazaki, 1992
Species:
W. satoi
Binomial name
Wakinosaurus satoi
Okazaki, 1992

Wakinosaurus (meaning "Wakino lizard") is a genus of theropod dinosaur from the Early Cretaceous (Valanginian-Barremian) Sengoku Formation of Kyushu, Japan. The genus is a tooth taxon, based solely on the middle section of a single tooth. [1]

Contents

Discovery and naming

In 1990 the ice hockey player Masahiro Sato in Fukuoka found the tooth of a theropod. The same year Yoshihiko Okazaki first reported on the find. [1] In 1992 Okazaki named the type species, Wakinosaurus satoi. The generic name refers to the Wakino Subgroup of the Kwanmon Group, of which the Sengoku Formation is a member. The specific name honours Sato. [2]

Description

The holotype is KMNH VP 000,016, a single damaged tooth, the crown of which must have been about seven centimetres long. Its base length is 32.9 millimetres (1.30 in), its base width 10.4 millimetres (0.41 in). It has about thirty serrations per five millimetres. [3]

Wakinosaurus was initially described as a megalosaurid but is today considered a nomen dubium and an indeterminate neotheropod. The holotype tooth is similar to a leaf with fine cutting serrations on both edges and according to Okazaki, it is similar to those of " Prodeinodon " kwangshiensis, which is also a dubious tooth taxon. In 2020, it was suggested that Wakinosaurus may represent a basal carcharodontosaurid theropod similar to Acrocanthosaurus . [4]

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References

  1. 1 2 Okazaki, Y., (1990), "Discovery of dinosaur remain from the Kwanmon Group", Abstract of the Annual Meeting of the Paleontological Society of Japan, 37
  2. Okazaki, Y. (1992). A new genus and species of carnivorous dinosaur from the Lower Cretaceous Kwanmon Group, northern Kyushu. Bulletin of the Kitakyushu Museum of Natural History11:87-90
    • Hasegawa, Y., Murata, M., Wasada, K. & Manabe M., 1992, "The First Carnosaur (Saurischia; Theropoda) from Japan: a Tooth from the Cenomanian Mifune Group of Kyushu", Science Reports of the Yokohama National University, 2(39): 41-49
  3. Chan-gyu Yun (2020). "A Carcharodontosaurid tooth from the Hasandong Formation (Lower Cretaceous) of South Korea". Mongolian Geoscientist. 50: 2–10. doi: 10.5564/mgs.v50i0.1325 .