Dakosaurus

The type species Dakosaurus maximus, meaning "greatest biter lizard", is known from fossil discoveries in Western Europe (England, France, Switzerland and Germany) of the Late Jurassic (Late Kimmeridgian-Early Tithonian). When isolated Dakosaurus teeth were first discovered in Germany, they were mistaken for belonging to the theropod dinosaur Megalosaurus. The type species D. maximus was originally named as a species of Geosaurus in 1846 by Theodor Plieninger, creating the species G. maximus. He gave the meaning of Greek dakos more correctly as "Beisser" [biter] in another description in 1859 in which he classified Dakosaurus as a dinosaur. Named in 1871 by Emanuel Bunzel, Fossil specimens referrable to Dakosaurus are known from Late Jurassic deposits from England, France, Switzerland, Germany, Poland, Russia, Argentina, and Mexico. Teeth referrable to Dakosaurus are known from Europe from the Oxfordian. Dacosaurus (Sauvage, 1873) is a misspelling of Dakosaurus, and thus a synonym. Dakosaurus andiniensis, meaning "biter lizard from the Andes", was first reported in 1985 from the Neuquén Basin, a very rich fossil bed in the Vaca Muerta, Argentina. However, it was not until 1996 that the binomen Dakosaurus andiniensis was erected. Dakosaurus nicaeensis, named in 1913 by Ambayrac, was mistakenly classified as a megalosaurid dinosaur; now it is assigned as the sole species in the genus Aggiosaurus. Buffetaut in 1982 demonstrated that it was in fact a metriorhynchid, closely related to, if not a member of Dakosaurus. As the type specimen is poorly preserved it is considered nomen dubium. Incomplete skull specimens of Dakosaurus have been discovered in Kimmeridgian age rocks from Mexico; they have not yet been referred to a specific species of Dakosaurus. ==Description==

All currently known species would have been large, measuring approximately long. Its body was streamlined for greater hydrodynamic efficiency, which along with its finned tail made it a more efficient swimmer than modern crocodilian species. ==Classification==

Dakosaurus–when it contained the species D. andiniensis, D. maximus, and D. manselii–had long been considered paraphyletic, that is, not consisting of a common ancestor and its descendants, until a 2012 study moved D. manselii to the formerly invalid genus Plesiosuchus. }} ==Palaeobiology==

'' Salt glands The incomplete skull specimens from the Mexican species of Dakosaurus preserves the chamber in which the well-developed salt glands (known from Geosaurus and Metriorhynchus) would have been housed. Unfortunately, there was no preservational evidence of the glands themselves. The enlarged supratemporal fenestrae of Dakosaurus skulls ensuring a powerful bite. As their skulls are triangular in shape, with deeply rooted, large, serrated teeth and a bulbous, deep, mandibular symphysis (like pliosaurs), dakosaurs would also have been able to twist feed (tear chunks of flesh off potential prey). The wear and spall patterns of Dakosaurus teeth suggest it cut large prey items apart into chunks it could swallow, further pointing to the genus being macroraptorial. == Palaeoecology ==

'' Dakosaurus maximus is one of several species of metriorhynchids known from the Altmühltal Formation (Solnhofen limestone, early Tithonian) of Bavaria, Germany. Alongside three other metriorhynchid species, it has been hypothesised that niche partitioning enabled several species of crocodyliforms to co-exist. Dakosaurus and Geosaurus giganteus would have been top predators of this Formation, both of which were large, short-snouted species with serrated teeth. The remaining two species (Cricosaurus elegans and Rhacheosaurus gracilis) and the teleosaurid Aeolodon would have fed mostly on fish. From the slightly older Nusplingen Limestone (late Kimmeridgian) of southern Germany, both D. maximus and C. suevicus are contemporaneous. As with Solnhofen, Dakosaurus was the top predator, while C. suevicus was a fish-eater. ==See also==