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23.01.2016 17:59 - Largest prehistoric animals Vol.1 Vertebrates part12 Fish - Bahariyan prey for Spinosaurus
Автор: valentint Категория: Забавление   
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Последна промяна: 03.12.2016 02:44


Retodus tuberculatus

Retodus is an extinct genus of prehistoric sarcopterygian or lobe-finned fish from North Africa and Nebraska.These reached lengths of approximately 3.5 m, roughly as much as a larger modern crocodile. However, lived in that very area still significantly larger crocodile, namely Sarcosuchus imperator, and Spinosaurus, which is why one can strongly assume that even part of this giant fish prey to even bigger predators. Here lungfish are themselves predators that feed on fish, amphibians, worms, insect larvae, as well as hard-shelled mollusks such as crustaceans, mussels and snails. Partly also plants are eaten, but these seem to be at least partially mitgefressen unintentionally when entangling prey. Most likely the food of giant lungfish will have been geared more towards larger prey, and especially the huge massive tooth plates (which will be discussed further below exact times), indicate a certain specialization in hard-shelled food. But which hard-shelled prey will probably have eaten a three and a half meters large lungfish? Most likely not only small mussels, snails or crustaceans. Presumably stood for turtles frequently on the menu, and especially smaller specimens may have not been a problem for the jaw. Turtles can partially amazing form large biomass, which is why it will not appear too far-fetched that they can be an important part of the diet of certain large predators in aquatic ecosystems. Also in some types of modern Crocodilia play at least locally turtles an important role in the diet. Considering the fact that lung fish are generally quite aggressive predators, can well assume that they recorded and all sorts of other vertebrates in their diet when the opportunity arose, whether floating in water reptiles, birds or even small dinosaurs.

 A lungfish of three and a half meters is pretty huge, but there was even greater . Only recently , namely in 2011 , a huge Ceratodus tooth from Nebraska was described . This mandibular was 117 mm long , and thus 17 mm longer than the largest Retodus tuberculatus tooth from Africa . From this giant lungfish is no longer known as one of the giant tooth plates, so of course is not entirely sure how they actually looked like during his lifetime. However, the tooth plates are those of modern Australian extremely similar lungfish, which are also in their body shape other better-known archaic style still so similar that it is certainly not resorted to far to use it as a direct reference. How extremely large these giant lung fish such Retodus tuberculatus and even more species in North America were, is also evident when one considers their weight. Based on the mentioned at the beginning the average weights of modern Australian lungfish I come for the former to a weight of about 437 kg, which is far more difficult than almost all of today's freshwater fish, and is only surpassed by some anadromous sturgeon, but in a large part of their lives spend sea. For the giant lungfish from Nebraska I'm at 4 m length even on a weight of 652 kg. That is more than four times as heavy as the largest documented European catfish, about three times as much as the heaviest South American Piraibas and more than twice as heavy as the largest Mekong giant catfish. As previously known only as extremely little fossils, of course you must also assume that individual specimens of giant lungfish have also become even greater. It is amazing that a freshwater ecosystem has enabled the development so huge fish.


Paranogmius

Paranogmius is an extinct genus of prehistoric bony fish that lived during the Cenomanian. Paranogmius was only known from very large, compressed vertebrae which made it impossible to identify this lost giant (and like most Stromer material these are now destroyed). Based on the size if Paranogmius' vertebrae this monster was even a bit bigger (this specimen is 3,5 m long, the Bahariya specimen was maybe 4 m long)


Bawitius

Bawitius is an extinct genus of giant polypterid from the Upper Cretaceous (lower Cenomanian) Bahariya Formation of Egypt. The genus etymology comes from Bawiti, the principal settlement of the Bahariya Oasis in Egypt. It is known from several ectopterygoid bones and some sparse scales.

Compared to modern polypterids, Bawitius was enormous: the Bawitius holotype ectopterygoid is five times larger than the one of Polypterus and the scales are unusually large, too: these remains suggest the living animal may have been up to 300 centimeters (9.8 feet) in length.
The morphology of Bawitius is different enough to justify its assignment to a new genus. Unique features of the genus are, for example, an anterioposteriorly elongated contact between the lateral process and the maxilla, a high, narrow ectopterygoid and the presence of 14 teeth in the main tooth row.
The scales are different, too, apart from size, from those of modern polypterids: they feature a discontinuous ganoine layer, a rectilinear shape, and small articular processes.
The existence of drastically different polypterids such as Bawitius and Serenoichthys corroborates the existence of a variety of polypterid fishes in the ecosystems of Late Cretaceous of North Africa


Atractosteus africanus

Atractosteus africanus was a big gar from the cretaceous of africa and europe, most remains are today known from France, the african fossils were found in Niger. Because of it's size and the habit of modern Atractosteus to bath in the sun and to breath air in waters with an low oxygen level speculated about the possibility to have here another snack for Spinosaurus.


Onchopristis

Onchopristis is a
genus of extinct giant sawfish that lived in the Lower Cretaceous to Upper Cretaceous in North Africa and New Zealand. It had an elongated snout lined laterally with barbed teeth.
Onchopristis is a large sawfish, known from remains throughout North America, North Africa and New Zealand. It was very large, up to 8 m (26.2 ft) long when fully grown.As with modern sawfish, Onchopristis's eyes were on top of its head, to spot predators rather than prey, and its mouth and gills were under its body.The rostrum, or snout, was around 2.5 m (8.2 ft) long, lined with barbed teeth.In the type species, O. numidus, each tooth had one barb, but in O. dunklei there were two to five barbs on each tooth, two to three in O. d. praecursor, and three to five in O. d. dunklei.The rostrum most likely would have had electrosensors to detect food in the water below them like most modern sharks and some rays. Onchopristis may have raked through the riverbed to find and then eat prey.

As an ancient member of the pristidae, Onchopristis would have been more closely related to rays than to sharks. Like modern day sawfish, Onchopristis would have used the rostrum that extended for as much as two and a half meters in front of it to sense prey. Once prey was detected, Onchopristis would swipe its rostrum towards it, impaling its victim upon the barbed spikes that ran down either side of the rostrum. The use of the rostrum as a sensory and killing device is a result of sawfish living near the bottom of their aquatic environments, and as such it is highly likely that Onchopristis shared this kind of lifestyle.






















Тагове:   сова,   paleo,   prehistoric animals,   giant fish,


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Автор: valentint
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