rdfs:comment
| - First appearing in the Late Jurassic, these small, featherless runners have a fragmentary and poorly-known early history. After the low-slung, Late Jurassic †Elaphrosaurus of Africa (and possibly North America as well), noasaurids are only known from the Southern Hemisphere, with Cretaceous forms including †Noasaurus and †Ligabueino from Argentina. These predators are best known for their slashing, sickle claws, which were thought to have evolved independently from the deinonychosaurs, but presumably used for the same purpose. However, it has been found that noasaurids actually carried these claws on their hands. †Velocisaurus, another noasaurid from the same time and place as Noasaurus, also represents the earliest record of the characteristic noasaurid feet, in which the first toe is los
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abstract
| - First appearing in the Late Jurassic, these small, featherless runners have a fragmentary and poorly-known early history. After the low-slung, Late Jurassic †Elaphrosaurus of Africa (and possibly North America as well), noasaurids are only known from the Southern Hemisphere, with Cretaceous forms including †Noasaurus and †Ligabueino from Argentina. These predators are best known for their slashing, sickle claws, which were thought to have evolved independently from the deinonychosaurs, but presumably used for the same purpose. However, it has been found that noasaurids actually carried these claws on their hands. †Velocisaurus, another noasaurid from the same time and place as Noasaurus, also represents the earliest record of the characteristic noasaurid feet, in which the first toe is lost, the second and fourth short and narrow and the third long and strong. Aside from a single bizarre skull from Madagascar belonging to the cretaceous Masiakasaurus knopfleri, and a few fragments from India, there is little else known of the pre-Cenozoic history of the clade Noasauridae. The oldest complete noasaurid skeleton comes from the Eocene of Argentina. These remains represent an animal that must have been quite similar to the living cain (Cain cursor), which inhabits modern Madagascar. Noasaurids seem to have vanished from South America when a meteorite struck 3.3 million years ago, though the paleontology of Spec is still in its infancy and precludes certainty in such conclusions. In any case there are no longer any noasaurs in South America; they have been replaced by cazadins.
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