''Dibothrosuchus'' is a genus of sphenosuchian, a type of

basal Basal or basilar is a term meaning ''base'', ''bottom'', or ''minimum''. Science * Basal (anatomy), an anatomical term of location for features associated with the base of an organism or structure * Basal (medicine), a minimal level that is nec ...

crocodylomorph Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. During Mesozoic and early Cenozoic times, cro ...

, the

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that comprises the crocodilians and their closest kin. It is known from several partial skeletons and skulls. These fossils were found in Lower Jurassic (Lower Pliensbachian, circa 186 million years old) rocks of Yunnan,

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

. ''Dibothrosuchus'' was a small terrestrial crocodylomorph that probably had a keen sense of hearing, and thus was probably a vocal animal like modern crocodilians.

History and description

''Dibothrosuchus'' was named in 1965 by D.J. Simmons based on a partial skull and skeleton collected by Father Oehler of

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from

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s near Huangchiatien. The type species is ''D. elaphros''. Additional remains of this genus were recovered in 1985 by a joint Chinese-US expedition. Fossils of ''Dibothrosuchus'' come from the Zhangjiawa Formation, being originally assigned to the Reds Beds of the Lufeng Formation, thus being geologically younger than other crocodylomorphs from the region. At least three partial skeletons and two skulls are known, along with isolated bones. ''Dibothrosuchus'' was first described as an ornithosuchid thecodont, but it was later reclassified as a sphenosuchid sphenosuchian. A second species, ''D. xingsuensis'', was named by Wu in 1986. After reexamination of the holotype Wu and

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found ''D. xingsuensis'' to be a synonym of ''D. elaphros'', leaving only one species in the genus. Dibothrosuchus BW

''Dibothrosuchus'' was not a large animal. From the tip of the snout to the occipital condyle, the skull of

IVPP The Institute of Vertebrate Paleontology and Paleoanthropology (IVPP; ) of China is a research institution and collections repository for fossils, including many dinosaur and pterosaur specimens (many from the Yixian Formation). As its name suggest ...

V 7907 is only long, and the body length of the individual is estimated as . In general form, ''Dibothrosuchus'' was a slender, long-tailed and long-limbed quadruped with a pointed snout. Unlike modern crocodilians, it was a terrestrial animal. The upper jaws had five small teeth per premaxilla (snout-tip bones) and seventeen per maxilla, with a small hole between the maxilla and premaxilla for an enlarged tooth in the lower jaw to fit. At least eleven teeth were present on each side of the lower jaw. Several small ridges were present on the top of the skull. The various parts of the skull that supported hearing were well-developed, indicating that ''Dibothrosuchus'' had a keen sense of hearing and was probably a vocal animal that could communicate with others of the same genus, like modern crocodilians. Two rows of

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ran along the midline of the spine.

References

{{Taxonbar, from=Q744899 Early Jurassic reptiles of Asia Early Jurassic crocodylomorphs Terrestrial crocodylomorphs Prehistoric pseudosuchian genera