Paralititan

Paralititan stromeri (live reconstruction)

  • Egypt ( Bahariyya oasis )
  • Paralititan stromeri

Paralititan was a genus of sauropod dinosaur from the group of Titanosauria that lived during the early Cretaceous ( Cenomanian ) in what is now Egypt.

She is known only by a partial skeleton that was discovered in 2000 in the Bahariyya oasis and in 2001 by Smith et al. has been described. The only known type ( type species ) this genus is P. stromeri. Paralititan possibly lived in a mangrove forest like ecosystem and is the first dinosaur that was detected from this ecosystem.

Naming

The genus name Paralititan is composed of the Greek words Paralos = " near the sea " (from παρα, para = " in ", " next " and ἅλς, neck = " salt ", " sea " ) and titanium. The Artepitheth stromeri honors the German paleontologist Ernst Stromer von Reichenbach, who conducted research in the early 1900s in the Bahariyya oasis and found, among other remains of four previously unknown dinosaur species.

Fund and Habitat

The partial skeleton ( holotype CGM 81119 ) consists of several vertebrae, elements of the shoulder girdle and the front legs: two fused pelvic vertebrae, the first and another anterior caudal vertebrae, ribs, an incomplete shoulder blade (scapula ), the left and right upper arm bone (humerus ), a metacarpal bone and some other elements. A Stromer described vertebrae (1912VIII64) might have also heard about Paralititan, but is lost.

The find dates geologically from the Bahariya Formation and thus the early Late Cretaceous ( Cenomanian ) attributed. The low-energy sediments at the site suggest a watt because the bones once were in the intertidal zone.

Found plant material belonged partly to Weichselia reticulata, a fossil tree fern, which is counted among the mangrove trees. Furthermore, plant roots were found in situ, which extend through the bone- bearing layer and show a limited water depth. The researchers assume that the animal before his death, the Mangrove visited - it is unlikely that the bones were swept into this place, because they were very close together and the shallow, vegetated Watt would have prevented a shipment.

When the bones of a theropod tooth cf Carcharodontosaurus was found that suggests that scavengers have eaten the carcass. The possibility that the tooth was washed on the location, also applies here because of the size of the tooth by 65 mm to be unlikely.

Description and systematics

Paralititan is one of the bulkiest sauropods that were ever found. The significantly prolonged at both ends humerus measures 1.69 meters in length, making it the longest known of a sauropod the Cretaceous.

For more size information remains speculative, although due to the sparse bone material. The comparisons with other titanosaurs show that Paralititan was perhaps smaller than the giant Argentinosaurus, the humerus was not found, but is estimated to have a length of 1.81 meters. Carpenter (2006) indicates the length of Paralititan with 26 meters, the calculation was carried out on physique of the better-known Saltasaurus. The weight of Paralititan is estimated by Burness and colleagues ( 2001) to 69 tons.

The describer arranged Paralititan a Titanosauridae within the family, as some similarities with other Titanosauriden exist. Thus, the posterior sacral vertebra no scooping out on, however, the tail vertebrae found is strongly procoel (on the front concave) and has a well-developed distal condyle ( posterior condyles ) on. In addition, the metacarpal bone at the distal (lower) was flattened end - which suggests that the finger bones were either significantly reduced or absent. However, the internal classification of Titanosauria is highly controversial. Many recent authors consider the Titanosauridae as invalid, which is why they often no longer appears in recent cladistic analyzes. Instead Paralititan is classified within the group of Lithostrotia.

Other features have been described as autapomorphies ( unique characteristics) and limits Paralititan of other genera from. These features include extensions to the scapula and the humerus, the shape of the caudal vertebra ( wider than high), and the rectangular shape of the radial condyle with a ( the condyle, of the elbow joint the humerus with the radius, the spoke connects ). These features also allow a clear distinction to Aegyptosaurus, another sauropod from the Bahariyya oasis, which was described by Stromer, whose remains have been lost. Aegyptosaurus whose humerus was 59% smaller than that of Paralititan, can not presently be classified more precisely and is within the Titanosauria incertae sedis as.

Paläofauna and meaning

Ernst Stromer had researched in the early 20th century in the Bahariyya oasis and a varied fauna described: Under the described vertebrates are fish, turtles, squamates, crocodiles, plesiosaurs and dinosaurs. Very large vertebrates include the 3.5 -meter-long coelacanth Mawsonia and the 10 -meter-long crocodile with a Stomatosuchus; but also the large theropod Spinosaurus, Carcharodontosaurus and Bahariasaurus. A large part of Stromers collection was destroyed in 1944 during an Allied bombing raid on Munich. Other discoveries were made ​​- Paralititan is the first from the Bahariyya oasis described land vertebrate since 1935.

The find is significant because dinosaur remains from the Late Cretaceous of Africa are rare. A better knowledge of these vertebrate fauna also helps to better understand the breakup of the southern continent Gondwana.

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