Carnotaurus

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Carnotaurus
Skeleton cast of Carnotaurus in the Chlupáč Museum in Prague

Skeleton cast of Carnotaurus in the Chlupáč Museum in Prague

Temporal occurrence
Upper Cretaceous (Lower Maastrichtian )
72 to 69.9 million years
Locations
Systematics
Lizard dinosaur (Saurischia)
Theropoda
Ceratosauria
Abelisauridae
Carnotaurus
Scientific name
Carnotaurus
Bonaparte , 1985
Art
  • Carnotaurus sastrei
Live artistic representation of Carnotaurus
Carnotaurus in size comparison with a human

Carnotaurus ("meat-eating bull") is a genus of theropod dinosaur from the Upper Cretaceous Argentina . So far only one species is known ( Carnotaurus sastrei ).

This two-legged carnivore was characterized by a very short and deep skull and a distinctive pair of large frontal horns. So far only a single skeleton has been found, but it has been completely preserved except for the lower sections of the legs and most of the tail and even includes impressions of the skin.

Carnotaurus is one of the Abelisauridae , a group of medium-sized to large theropods whose fossils were found in the Cretaceous of South America, Africa and India. Scientifically described as early as 1985, Carnotaurus was for a long time the only member of the Abelisauridae of which an almost complete skeleton was known. Various biomechanical studies provide information on possible intra-species fighting, on the diet and on the speed of this animal.

features

Find and height

The only skeleton was found in the original anatomical network. The middle and rear sections of the tail as well as the lower areas of both hind legs are missing, as they were destroyed by weathering before the skeleton was discovered . When it was discovered, the skeleton lay on the right side and showed a curved neck - this pose, also known as the death pose , is typical for fossils of long-necked terrestrial vertebrates and probably on the post-mortem effects of a pretensioned one that runs along the spine band (the ligamentum elasticum interlaminar attributable). It is an adult individual, as can be deduced from the degree of fusion of the bone sutures of the brain skull .

The only known specimen is estimated to be 8 to 9 meters long. This made Carnotaurus one of the largest known representatives of the Abelisauridae - only Ekrixinatosaurus and possibly the Abelisaurus , known only through a skull, could have been similar in size or even larger. Weight estimates vary depending on the study and the method used. Dale Russell estimates the weight at 1.35 tons based on the length of the thigh bone . Gerardo Mazzetta and colleagues (1998) use a volumetric method to calculate the weight to 1.5 tons by calculating the body volume and multiplying this by an estimated mean tissue density of 1000 kg per m³. Gerardo Mazzetta and colleagues (2004) were able to calculate a weight of 2.1 tons, based on the length of various limb bones.

skull

The skull has survived almost completely and is in good condition, although it is crushed on the sides, especially in the area of ​​the snout. Measured from the tip of the snout ( intermaxillary bone ) to the back of the square leg , it is 59.6 cm long, and measured from the top of the occiput ( occipital ridge ) to the underside of the cheekbone 42.5 cm high. This made the skull relatively shorter and deeper than that of all other known Abelisaurids. Such a unique feature is also known as autapomorphism and serves to distinguish this genus from other genera. With the exception of the brain skull , the skull showed numerous loose bone sutures , which indicates a high degree of mobility of the skull bones in relation to one another ( skull kinesis ). The eyes were relatively small and were located in the upper area of ​​the keyhole-shaped eye sockets . This upper area was rotated slightly forwards, which possibly allowed three-dimensional vision . The snout was relatively broad and rounded, and not tapered as in most of the original theropods such as Ceratosaurus .

Skull cast

The surface of the facial skull was textured with numerous bumps such as small pits and appendages. This texturing was particularly pronounced on the paired nasal bone and was present in a similar form in various other abelisaurids. This feature may indicate that the facial skeleton covering skin horny was. There was a pair of large, very thick frontal horns above the eyes, which are formed by the pair of frontal bones . Such frontal horns were not found in any other theropod, which is why this feature serves to distinguish it from other genera (autapomorphy). These short horns, flat on top, were oriented laterodorsally (to the side and upwards) and measured a length of almost 15 cm. It is possible that they formed the bony base of a coating of horny substance, which means that the horns in living animals could have been significantly longer.

The teeth appeared relatively slender and longer than many other abelisaurids, which typically had very short teeth. There were 12 teeth on each side of the upper jaw; In the paired intermaxillary bone, as in other abelisaurids, there were four more teeth each. There were 15 teeth on each side of the lower jaw. Seen from the side, the jaws were more curved than other Abelisaurids, as the upper edge of the lower jaw shows. The upper jaw appears to be more curved on the found skull than it actually was in the living animal, because the intermaxillary bone is pushed up onto the nasal bone as a result of the lateral crushing of the skull. The lower jaw was built slender and fragile - the dental (the tooth-bearing, anterior bone of the lower jaw) was connected to the posterior jawbone by just two contact points.

Trunk skeleton and limbs

Sixth caudal vertebra (incompletely preserved) in a) side view, b) front view and c) top view. The arrows mark the transverse processes.
Hand structure of Carnotaurus with the hand rays I – IV

The spine is completely preserved up to the sixth caudal vertebra and found in the original anatomical union. The posterior caudal vertebrae are missing, only the presumably twelfth caudal vertebra is incomplete. The spine consists of ten cervical vertebrae, twelve vertebrae and seven sacral vertebrae . The cervical vertebrae showed only very small spinous processes , while the two processes behind the spinous processes, the epipophyses , were particularly large and formed the highest points of the vertebrae. Thus, viewed from above, the cervical spine was not dominated by a single row of spinous processes, but rather by a double row of large epipophyses. The enlarged epipophyses indicate that the muscles responsible for lateral movements of the neck were well developed. Although also present in other abelisaurids, this feature was very pronounced in Carnotaurus . The tail vertebrae had a very unusual morphology for theropods : The transverse processes (lateral outgrowths of the vertebral arches) were not aligned horizontally, but pointed steeply upwards. In some caudal vertebrae, these processes were higher than the central spinous processes. The transverse processes were inclined backwards and showed a forward-facing, crescent-shaped end, which was presumably connected to the transverse process of the preceding vertebra. These special adaptations were particularly pronounced in Carnotaurus , but were also found in other South American Abelisaurids ( Aucasaurus , Ilokelesia and Scorpiovenator ), while they were absent in Abelisaurids from Madagascar and India. Possibly these adaptations indicate an enlarged musculature to drive the legs (see below).

The arms were only formed as extremely receded, shortened and probably functionless remains. The extremely shortened forearm, which was only a quarter of the length of the upper arm, was also remarkable. This construction plan was typical for representatives of the Abelisauridae - in comparison with related genera, however, the arms of Carnotaurus were proportionally even shorter and also more robust. The hands of Carnotaurus were found to be anatomically connected, although some bones were moved from their original position or are missing. The hand was four-pointed and also severely receded. As with Aucasaurus , the metacarpal bones bordered directly on the forearm; Carpal bones were completely absent. The fourth metacarpal bone was the largest bone in the hand and more than twice the size of the second metacarpal - in contrast to the closely related Aucasaurus , in which the first metacarpal was the largest. The lower end of the fourth metacarpal bone was conical in shape and showed no articular surface, which is why there were obviously no finger bones in the fourth hand ray. The first hand ray was probably also missing finger bones, while the second hand ray had a claw directly adjacent to the second metacarpal bone and the third hand ray had a finger bone and a claw.

Overall, the pelvic bones were relatively long, slender and straight. Of the hind legs, only both thigh bones and the top third of both shins have been preserved, the lower areas of the legs and feet are missing. The legs were comparatively long and slender; the left femur measured a length of 103 cm, while the bone shaft measured an average of only 11 cm in diameter.

skin

Carnotaurus is the first finding of a large theropod dinosaur in which the skin is relatively completely preserved. For example, skin prints from different parts of the body from the right side of the skeleton have been passed down, some of which are directly associated with the bones. One fragment each comes from the lower jaw and from the anterior section of the neck, while another fragment is from the shoulder girdle and two other fragments from the chest. The largest surviving fragment comes from the front part of the tail. Originally, the right side of the skull was also covered with various fragments of skin impressions, but this only became apparent after the skull had been dissected, as a result of which these fragments were largely lost.

The skin differed only slightly in different parts of the body. It consisted of a mosaic of polygonal, non-overlapping scales with a diameter of about 5 mm, which were interrupted by thin, parallel furrows. In contrast to other known theropod skin prints, those of Carnotaurus showed conical, button-like structures that were typically 4 to 5 cm in diameter and had a flat crest on top. These structures were spaced 8-10 cm apart in irregular rows along the sides of the animal. Presumably, these structures consisted of several individual scales condensed into an overall complex. No ossification could be detected in connection with these structures.

Systematics

Cladogram , simplified from Canale and colleagues, 2009:
  Abelisauridae  

 Rugops


   

 Abelisaurus


  Carnotaurinae  

 Majungasaurus


  Brachyrostra  
  Carnotaurini  

 Carnotaurus


   

 Aucasaurus



   

 Ilokelesia


   

 Scorpiovenator


   

 Ekrixinatosaurus






Template: Klade / Maintenance / 3

Template: Klade / Maintenance / Style
Systematic position of Carnotaurus

Carnotaurus is a member of the Abelisauridae, a group within the Ceratosauria that is restricted to the southern land masses ( Gondwana ) . Carnotaurus is considered to be the most specialized and derived (advanced) representative of this group: various features of this group, such as the shortening of the skull and the shortening of the arms, were more pronounced in Carnotaurus than in any other Abelisaurid.

The relationships within the Abelisauridae are highly controversial. The closest relative ( sister genus ) of Carnotaurus is usually either Majungasaurus or Aucasaurus , depending on the study . This ambiguity is mainly due to the fact that the skull of Aucasaurus is little known. Another study suggests that Carnotaurus is not closely related to either Aucasaurus or Majungasaurus , but is the sister genus of Ilokelesia .

Carnotaurus is the eponymous genus of two subgroups of the Abelisauridae, which are not accepted and used by all researchers: the Carnotaurinae and the Carnotaurini . The Carnotaurinae are intended to summarize all derived representatives of the Abelisauridae, excluding the basal (original) Abelisaurus . The Carnotaurini group is used by those researchers who classify Aucasaurus as the closest relative of Carnotaurus and describes the clade formed by these two genera .

Research history and naming

The skeleton ( holotype , copy number MACN-CH 894) was recovered in 1984 by an expedition led by José Bonaparte . This expedition was the eighth paleontological expedition conducted in Patagonia in a National Geographic Society- funded project on the Jurassic and Cretaceous terrestrial vertebrate fauna of South America. The location is on the land of the farm "Pocho Sastre" near Bajada Moreno in the Telsen department in the Argentine province of Chubut . The fossils were embedded in a very hard rock - a concretion of hematite - which complicated and extended their preparation. Today they are kept in the collection of the Museo Argentino de Ciencias Naturales Bernardino Rivadavia in Buenos Aires .

In 1985, José Bonaparte published a preliminary description of the skull and named the new species and genus Carnotaurus sastrei . The name Carnotaurus ( Latin carno - "meat"; Latin taurus - "bull") means something like "carnivorous bull" and indicates the unusual frontal horns of this carnivore. In 1990, José Bonaparte, together with Fernando Novas and Rodolfo Coria, published a more extensive description of the skull and the postcranial skeleton . More recent studies focused on this genus deal with biomechanics and establish paleobiological implications or describe parts of the skeleton such as the skull or the arms, the anatomy of which was not or only insufficiently discussed in the previous descriptions. Up until the discovery of Aucasaurus, Carnotaurus was the most complete surviving member of the Abelisauridae. Today, with the Aucasaurus , Majungasaurus and Scorpiovenator, other well-preserved Abelisaurid finds are known that make it possible to re-examine various features of the Carnotaurus skeleton, the interpretation of which was previously controversial.

Paleohabitat

Although the site was originally ascribed to the uppermost area of ​​the Gorro Frigio Formation, which was deposited at the turn of the Lower and Upper Cretaceous ( Albium or Cenomanium ), it is now ascribed to the much younger lower area of ​​the La Colonia Formation , which was only deposited at the end of the Upper Cretaceous in the Lower Maastrichtian .

The La Colonia Formation is open to a large extent on the southern slopes of the North Patagonian Massif ( Comarca Norpatagónica ) and consists of continental to marginal marine sedimentary rocks . The eastern part of the formation can be divided into three facies associations . The majority of the vertebrate fossils of the formation, including the Carnotaurus skeleton, come from the second facies association: finds include both terrestrial and aquatic vertebrates and include the remains of lungfish from the Ceratodontidae group , crocodiles , turtles , plesiosaurs , lizards , snakes , dinosaurs and mammals . The deposit area ( palaeoenvironment ) of the second facies association is interpreted as an estuary , a mud flats or a coastal plain . The climate at the time of the deposition was presumably seasonal, with dry seasons alternating with rainy seasons.

Paleobiology

Function of the frontal horns and skin

Skull cast at the Kenosha Dinosaur Discovery Museum in Kenosha

Carnotaurus is the only known theropod with large frontal horns. Various hypotheses try to clarify the function of these frontal horns. Possible functions as a weapon or as a shock absorber in intra-species fights are frequently discussed; however, the horns could also have had a visual function and were used for display. Gerardo Mazzetta and colleagues (1998) suggest alternatively a function as a hunting weapon. The horns could have been used to kill or injure small prey. Such a function of horns has not yet been described in the animal kingdom.

Gregory Paul (1988) already suspected that the frontal horns were used in fights with conspecifics. As this author points out, the greatly reduced eye sockets may have reduced the risk of eye injury in such fights. Daniel Chure (1998), on the other hand, argues that the frontal horns were very broad and show a flat top, which indicates that possible fights would have been fought primarily by hitting the top of the skull. He also notes that the reduced eye sockets could not be associated with fighting - for example, other hornless major thermopods, such as Abelisaurus , Acrocanthosaurus, and Carcharodontosaurus , would also have reduced eye sockets.

Gerardo Mazzetta and colleagues (1998) come to the conclusion that the neck muscles could absorb the forces that occur when the skulls collide head-on. The neck muscles were strong enough to cushion a shock that occurs when two animals collide with their skulls at a speed of 5.7 m / s each. A similar value is assumed for the recent white rhinoceros .

A more recent study by Gerardo Mazzetta and colleagues (2009) uses a finite element analysis carried out on a digital three-dimensional skull model to investigate how the skull behaves mechanically when it bites and during possible fights. According to this study, the skull was unable to withstand violent frontal impacts, but was able to effectively distribute compression forces on the horns without affecting the brain. The researchers therefore suspect that fights were not fought by wrestling, but mainly by pushing the horns, similar to recent cattle like bison .

Stephen Czerkas (1997) suspects that the conical skin structures that covered the sides of the animal in rows served as protection during fights against conspecifics and other theropods. This author points to the neck of the green iguanas ( iguana ), which shows similar structures that provide limited protection during turf wars .

Function of the jaw and cranial kinesis

Gerardo Mazzetta and colleagues (1998, 2009) reconstruct the jaw muscles of Carnotaurus and come to the conclusion that the Carnotaurus bite was less powerful but faster compared to other theropods such as Ceratosaurus or Allosaurus . From this, these researchers conclude that Carnotaurus mainly hunted relatively small prey. Studies on recent crocodiles show that the ability to grab hold of quickly is more important than a high bite force when hunting small prey. Gerardo Mazzetta and colleagues (2009) also come to the conclusion that the skull was designed to withstand great loads, such as those that occur when pulling large pieces of prey. These researchers therefore suspect that Carnotaurus was also able to hunt larger prey.

Researchers working with François Therrien (2005) contradict the results of Gerardo Mazzetta and colleagues. In their study of the biomechanics of the lower jaw of various theropods, these researchers conclude that the jaws of the Abelisaurids Majungasaurus and Carnotaurus had analogies with those of the Komodo dragon . The strength of the lower jaw or the bending strength would decrease linearly towards the front - this pattern is found in animals whose jaws are not suitable as a precision tool for catching small prey. The researchers suspect that the jaws of Carnotaurus and Majungasaurus were designed to inflict slit wounds. In addition, these researchers come to the conclusion that Carnotaurus showed a powerful bite - the bite force is twice as great as that of the Mississippi alligator . The researchers conclude that Carnotaurus preferred to hunt large prey, which it might ambush.

Robert Bakker (1998) also suspects that Carnotaurus was adapted to hunting very large prey, especially sauropods . This researcher recognizes in various characteristics, such as the short snout, the relatively small teeth and the strongly pronounced occiput , convergent developments to Allosaurus , which was also adapted to the hunting of sauropods. According to Robert Bakker, the upper jaws of Allosaurus and Carnotaurus may have been used like a sawn club to inflict wounds, with large sauropods weakening with repeated attacks.

Gerardo Mazzetta and colleagues (1998) suspect that the kinesis of the skull - the mobility of the skull bones relative to one another - was more pronounced than in any other known dinosaur. The researchers conclude that Carnotaurus may have swallowed smaller prey whole. In contrast to the structure of the rest of the skull, the posterior roof of the skull is firmly fused with the skull, which leads to an increased stability of this area. The researchers suspect that this stable area was used to accommodate the forces transmitted through the horns as they would occur in possible combat.

Running speed and turning ability

Reconstructed cross section through the tail of Carnotaurus . The upwardly directed transverse processes and the tail muscles can be seen

Gerardo Mazzetta and colleagues (1998, 1999) estimate the extent to which Carnotaurus was able to run fast, based on the resistance of the leg bones to bending moments occurring while running , which is calculated from various dimensions of the thigh bone and the assumed body weight. Leg bones are heavily stressed by bending moments, such as those that occur particularly when running fast. The researchers conclude that Carnotaurus was a fast runner who was better adapted to fast running than a human, but significantly less than an African ostrich .

The caudal vertebrae show transverse processes that are steeply upwards. Scott Persons and Philip Currie (2011) state that this feature increased the space available for the caudofemoralis muscle . The caudofemoralis muscle was the most important muscle for locomotion and attaches to the fourth trochanter of the thigh bone; a contraction of this muscle pulls the hind leg to the back. The researchers calculate the enlarged caudofemoralis muscle of Carnotaurus at a weight of 111-137 kg per leg, so this muscle in Carnotaurus was larger than in any other theropod examined for this characteristic. Based on these results, these researchers suspect that Carnotaurus was a fast sprinter and possibly one of the fastest major theropods.

Scott Persons and Philip Currie (2011) also found that the upward transverse processes reduced the space available for the epaxial muscles running along the spinous processes, the longissimus and the spinalis muscles . However, these two muscles were responsible for the stability as well as for the horizontal and vertical mobility of the tail. The elongated transverse processes were articulated with one another at their upper ends, which, according to these researchers, ensured the stability of the tail despite the reduced epaxial musculature. However, this further restricted the mobility of the tail, and with it the ability of the animal to turn: the hip and the tail behaved as a unit when turning, while other theropods could turn the hip first and then the tail.

Web links

Commons : Carnotaurus  - Collection of images, videos and audio files

supporting documents

Main literature

  • José F. Bonaparte , Fernando E. Novas , Rodolfo A. Coria : Carnotaurus sastrei Bonaparte, the horned, lightly built carnosaur from the Middle Cretaceous of Patagonia (= Contributions in Science. No. 416, ISSN  0459-8113 ). Natural History Museum of Los Angeles County, Los Angeles CA 1990, digitized version (PDF; 4.99 MB) .
  • Stephen A. Czerkas, Sylvia J. Czerkas: The Integument and Life Restoration of Carnotaurus. In: Donald L. Wolberg, Edmund Stump, Gary Rosenberg (Eds.): Dinofest International. Proceedings of a Symposium held at Arizona State University. Academy of Natural Sciences, Philadelphia PA 1997, ISBN 0-935868-94-1 , pp. 155-158.
  • Gerardo V. Mazzetta, Richard A. Fariña, Sergio F. Vizcaíno: On the Paleobiology of the South American horned Theropod Carnotaurus Sastrei Bonaparte. In: Gaia. Revista de Geociências. Vol. 15, 1998, ISSN  0871-5424 , pp. 185-192.
  • Gerardo V. Mazzetta, Adrián P. Cisilino, R. Ernesto Blanco, Néstor Calvo: Cranial mechanics and functional interpretation of the horned carnivorous dinosaur Carnotaurus sastrei. In: Journal of Vertebrate Paleontology. Vol. 29, No. 3, 2009, ISSN  0272-4634 , pp. 822-830, doi : 10.1671 / 039.029.0313 .
  • Javier Ruiz, Angélica Torices, Humberto Serrano, Valle López: The hand structure of Carnotaurus sastrei (Theropoda, Abelisauridae): implications for hand diversity and evolution in abelisaurids. In: Palaeontology. Vol. 54, No. 6, 2011, ISSN  0031-0239 , pp. 1271-1277, doi : 10.1111 / j.1475-4983.2011.01091.x .
  • W. Scott Persons, Philip J. Currie : Dinosaur Speed ​​Demon: The Caudal Musculature of Carnotaurus sastrei and Implications for the Evolution of South American Abelisaurids. In: PLoS ONE . Vol. 6, No. 10, 2011, e25763, doi : 10.1371 / journal.pone.0025763 .

Supplementary literature

  • Robert T. Bakker : Brontosaur Killers: Late Jurassic Allosaurids as Saber-Tooth Cat Analogues. In: Gaia. Revista de Geociências. Vol. 15, 1998, pp. 145–158, digital version (PDF; 4.95 MB) .
  • José F. Bonaparte: A horned Cretaceous carnosaur from Patagonia. In: National Geographic Research. Vol. 1, 1985, ISSN  8755-724X , pp. 149-151.
  • José F. Bonaparte: Cretaceous tetrapods of Argentina. In: Munich geoscientific treatises. Row A: Geology and Paleontology. Vol. 30, 1996, ISSN  0177-0950 , pp. 73-130.
  • Jorge O. Calvo , David Rubilar-Rogers, Karen Moreno: A new Abelisauridae (Dinosauria: Theropoda) from northwest Patagonia. In: Ameghiniana. Vol. 41, No. 4, 2004, ISSN  0002-7014 , pp. 555-563, digitized version (PDF; 939.68 kB) .
  • Juan I. Canale, Carlos A. Scanferla, Federico L. Agnolin, Fernando E. Novas : New carnivorous dinosaur from the Late Cretaceous of NW Patagonia and the evolution of abelisaurid theropods. In: The natural sciences . Vol. 96, No. 3, 2009, pp. 409-414, doi : 10.1007 / s00114-008-0487-4 .
  • Ariana Paulina Carabajal: The braincase anatomy of Carnotaurus sastrei (Theropoda: Abelisauridae) from the Upper Cretaceous of Patagonia. In: Journal of Vertebrate Paleontology. Vol. 31, No. 2, 2011, pp. 378-386, doi : 10.1080 / 02724634.2011.550354 .
  • Matthew T. Carrano, Scott D. Sampson: The Phylogeny of Ceratosauria (Dinosauria: Theropoda). In: Journal of Systematic Palaeontology. Vol. 6, No. 2, 2008, ISSN  1477-2019 , pp. 183-236, doi : 10.1017 / S1477201907002246 .
  • Daniel Chure: On the Orbit of Theropod Dinosaurs. In: Gaia. Revista de Geociências. Vol. 15, 1998, pp. 233-240, digital version (PDF; 2.53 MB) .
  • Rodolfo A. Coria , Luis M. Chiappe , Lowell Dingus : A new close relative of Carnotaurus sastrei Bonaparte 1985 (Theropoda: Abelisauridae) from the Late Cretaceous of Patagonia. In: Journal of Vertebrate Paleontology. Vol. 22, Vol. 2, 2002, pp. 460-465, doi : 10.1671 / 0272-4634 (2002) 022 [0460: ANCROC] 2.0.CO; 2 .
  • Martín D. Ezcurra, Federico L. Agnolin, Fernando E. Novas: An abelisauroid dinosaur with a non-atrophied manus from the Late Cretaceous Pari Aike Formation of southern Patagonia. In: Zootaxa . No. 2450, 2010, pp. 1–25, digitized version (PDF; 815.22 kB) .
  • Gerardo V. Mazzetta, Richard A. Fariña: XIV jornadas Argentinas de paleontologia de vertebrados. Estimacion de la capacidad atlética de Amargasaurus cazaui Salgado y Bonaparte, 1991, y Carnotaurus sastrei Bonaparte, 1985 (Saurischia, Sauropoda-Theropoda). In: Ameghiniana. Vol. 36, No. 1, 1999, pp. 105-106.
  • Gerardo V. Mazzetta, Per Christiansen, Richard A. Fariña: Giants and Bizarres: Body Size of Some Southern South American Cretaceous Dinosaurs. In: Historical Biology. Vol. 16, No. 2/4, 2004, ISSN  0891-2963 , pp. 71-83, doi : 10.1080 / 08912960410001715132 , digitized version (PDF; 5747.66 kB) .
  • Fernando E. Novas: The age of dinosaurs in South America. Indiana University Press, Bloomington IN 2009, ISBN 978-0-253-35289-7 .
  • Rosendo Pascual, Francisco J. Goin, Pablo González, Alberto Ardolino, Pablo F. Puerta: A highly derived docodont from the Patagonian Late Cretaceous: evolutionary implications for Gondwanan mammals. In: Geodiversitas. Vol. 22, No. 3, 2000, ISSN  1280-9659 , pp. 395-414.
  • Gregory S. Paul : Ceratosaurs. In: Gregory S. Paul: Predatory Dinosaurs of the World. A complete and illustrated guide. Simon and Schuster, New York NY et al. 1988, ISBN 0-671-61946-2 .
  • Achim G. Reisdorf, Michael Wuttke : Re-evaluating Moodie's Opisthotonic-Posture Hypothesis in Fossil Vertebrates. Part I: Reptiles — the taphonomy of the bipedal dinosaurs Compsognathus longipes and Juravenator starki from the Solnhofen Archipelago (Jurassic, Germany). In: Palaeobiodiversity and Palaeoenvironments. Volume 92, No. 1, 2012, ISSN  1867-1594 , pp. 119-168, doi : 10.1007 / s12549-011-0068-y .
  • Scott D. Sampson, Lawrence M. Witmer : Craniofacial Anatomy of Majungasaurus Crenatissimus (Theropoda: Abelisauridae) From the Late Cretaceous of Madagascar. Scott D. Sampson, David W. Krause (eds.): Majungasaurus crenatissimus (Theropoda: Abelisauridae) from the late Cretaceous of Madagascar (= Journal of Vertebrate Paleontology. Vol. 27, Supplement to No. 2, 2007 = Society of Vertebrate Paleontology . Memoir. No. 8). Society of Vertebrate Paleontology, Northbrook IL 2007, pp. 32-104, doi : 10.1671 / 0272-4634 (2007) 27 [32: CAOMCT] 2.0.CO; 2 .
  • Philip Senter: Vestigial skeletal structures in dinosaurs. In: Journal of Zoology. Vol. 280, No. 1, 2010, ISSN  0022-5460 , pp. 60-71, doi : 10.1111 / j.1469-7998.2009.00640.x .
  • Paul C. Sereno , Jeffrey A. Wilson, Jack L. Conrad: New dinosaurs link southern landmasses in the Mid-Cretaceous. In: Proceedings of the Royal Society. Series B: Biological Sciences. Vol. 271, No. 1546, 2004, ISSN  0950-1193 , pp. 1325-1330, doi : 10.1098 / rspb.2004.2692 .
  • Juliana Sterli, Marcelo S. De La Fuente: A new turtle from the La Colonia Formation (Campanian-Maastrichtian), Patagonia, Argentina, with remarks on the evolution of the vertebral column in turtles. In: Palaeontology. Vol. 54, No. 1, 2011, pp. 63-78, doi : 10.1111 / j.1475-4983.2010.01002.x .
  • François Therrien, Donald M. Henderson, Christopher B. Ruff: Bite Me: Biomechanical Models of Theropod Mandibles and Implications for Feeding Behavior. In: Kenneth Carpenter (Ed.): The carnivorous dinosaurs. Indiana University Press, Bloomington IN et al. 2005, ISBN 0-253-34539-1 , pp. 179-237.
  • Ronald S. Tykoski, Timothy Rowe : Ceratosauria. In: David B. Weishampel , Peter Dodson , Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 47-70.
  • Rubén D. Juárez Valieri, Juan D. Porfiri, Jorge O. Calvo: New Information on Ekrixinatosaurus novasi Calvo et al 2004, a giant and massively-constructed Abelisauroid from the "Middle Cretaceous" of Patagonia. In: Jorge Calvo, Juan Porfiri, Bernardo González Riga, Domenica Dos Santos (eds.): Paleontología y Dinosaurios desde América Latina. (= Series Documentos y Testimonios. Aportes. No. 24). EDIUNC, Mendoza 2011, ISBN 978-950-39-0265-3 , pp. 161-169, digital version (PDF; 643.51 kB) .
  • Jeffrey A. Wilson, Paul C. Sereno, Suresh Srivastava, Devendra K. Bhatt, Ashu Khosla, Ashok Sahni: A new abelisaurid (Dinosauria, Theropoda) from the Lameta Formation (Cretaceous, Maastrichtian) of India (= The University of Michigan. Contributions from the Museum of Paleontology. Vol. 31, No. 1, 2003, ISSN  0097-3556 ). The University of Michigan - Museum of Paleontology, Ann Arbor MI 2003, online .

Individual evidence

  1. ↑ a b c d e Novas 2009 , pp. 276–279
  2. ↑ a b c Bonaparte et al. 1990 , p. 2
  3. ↑ a b c d e f g Czerkas 1997
  4. ^ Reisdorf and Wuttke 2012 , p. 159
  5. ↑ a b Carabajal 2011 , p. 379
  6. ↑ Bonaparte et al. 1990 , p. 38
  7. ↑ Valieri and Porfiri 2011 , p. 162
  8. ↑ a b c d e Carrano and Sampson , p. 191
  9. ↑ Calvo et al. 2004 , p. 556
  10. ↑ Valieri and Porfiri 2011 , p. 163
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  34. ↑ Ezcurra et al. 2010 , p. 14
  35. ↑ a b c Carrano and Sampson , pp. 200, 202
  36. ^ Paul Sereno: Carnotaurinae. (No longer available online.) In: Taxon Search. Archived from the original on May 16, 2012 ; Retrieved August 4, 2014 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.taxonsearch.org
  37. ↑ a b Bonaparte 1985
  38. ↑ Ben Creisler: Dinosauria Translation and Pronunciation Guide. Archived from the original on November 11, 2011 ; Retrieved August 4, 2014 .
  39. ^ Carabajal 2011
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  47. ^ Mazzetta and Fariña 1999
  48. ↑ Mazzetta et al. 1998 , pp. 186, 190
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