Joanusaurus: Difference between revisions

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*{{extinct}}'''''J. iscastae''''' <br/><small> [[Phillipe d'Everard (paleontologist)|d'Everard]] ''et al.'', 1919</small>

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''Joanusaurus'' was a typical large bipedal theropod, having a massive skull on a short neck, a long, slightly sloping tail, and reduced forelimbs. ''Joanusaurus davignoni'', the best-known species, had an average length of 9.7 meters (32 feet), with the largest definitive ''Joanusaurus'' specimen (JSNH 432) estimated at 11.6 meters (38 feet) long, with an estimated weight of 2.5 metric tons (2.7 short tons). In his 1976 monograph on ''Joanusaurus'', Cadeaux mentioned a range of bone sizes which he interpreted to show a maximum length of 12 to 13 m (39 to 43 ft). As with dinosaurs in general, weight estimates are debatable, and since 1980 have ranged between 1,500 kilograms (3,300 pounds), 1,000 to 4,000 kg (2,200 to 8,800 lb), and 1,010 kilograms (2,230 pounds) for modal adult weight (not maximum). In a 2005 article, [[Johann Fürster]], a specialist on the [[Greater Levantine Formation]], suggests that 1,000 kg (2,200 lb) is reasonable for large adults of ''J. davignoni'', but that 700 kg (1,500 lb) is a closer estimate for individuals represented by the average-sized thigh bones he has measured, although Fürster's finding have been met with critique from other experts.  

The skull and teeth of ''Joanusaurus'' were modestly proportioned for a theropod of its size. Paleontologist [[Phillipe d'Everard (paleontologist)|Phillipe d'Everard]] gives a length of 845 mm (33.3 in) for a skull belonging to an individual he estimates at 7.9 m (26 ft) long. Each premaxilla (the bones that formed the tip of the snout) held five teeth with D-shaped cross-sections, and each maxilla (the main tooth-bearing bones in the upper jaw) had between 14 and 17 teeth; the number of teeth does not exactly correspond to the size of the bone. Each dentary (the tooth-bearing bone of the lower jaw) had between 14 and 17 teeth, with an average count of 16. The teeth became shorter, narrower, and more curved toward the back of the skull. All of the teeth had saw-like edges. They were shed easily, and were replaced continually, making them common fossils. Its skull was light, robust and equipped with dozens of sharp, serrated teeth. Its skull averaged 1 m (3.3 ft) long but could possibly reach 1.5 m (4.9 ft).

The discovery and early study of ''Joanusarus'' came in 1878 when a friend of the paleontologist [[Thibault d'Avignon]] bought a petrified bone from a curio shop in [[Koop]], [[Yonderre]]. Bones such as this had long been known to the populace of the industrious [[Vollardic Mountains]] and were known as the bones of ancient giants in local folklore. When examined by d'Avignon he recognized it as the ''radius'' bone of a large theropod and tentatively assigned it to the genus ''[[Vollardisaurus]]''. d'Avignon secured funding for an expedition to the [[Vollardic Mountains]] in August of 1878 where, aided by local silver miners, more remains were uncovered. In September of 1878 d'Avignon's expedition uncovered remains of a ''Joanusaurus'' in a disused silver mine. With about 31% of the skeleton present in the form of fragmentary bones including parts of three vertebrae, a rib fragment, a toe bone, and, most useful for later discussions, a near-complete skull, d'Avignon pronounced this to be a new species entirely and gave these remains the formal name ''Joanusaurus davignoni''. The species name means "Joanus' lizard" and is named in honour of [[Joanus de Martigueux]], founder of [[Yonderre]]. The type name ''davignoni'' is named for d'Avignon himself.

===Caphiria===