carnosauria

Carnosauria

    The carnosaurians, stripped of Tyrannosauroidea but still powerful, are in a state of flux, especially considering the vast wealth of MJ and LJ dinosaur remains coming out of China in the last twenty years that has opened large new families in Theropoda and Sauropoda. Some workers prefer the name Allosauria for this group. All carnosaurians have cervical verts with a hollow on the rear and a ball in front (opisthocoelous).
    Allosauroidea, traditionally a more inclusive classification within Carnosauria, includes four main divisions: Sinraptoridae, Allosauridae, Carcharodontosauridae, and Neovenatoridae (note that the paper introducing Neovenatoridae and Megaraptora did not include Carnosauria, so I applied Webmaster License to shoehorn it in). The members of Allosauroidea are very similar in overall form and epitomize the body plan of the basic big theropod: three fingers per hand, large head and teeth, small horns or ridges in front of the eye, and somewhere between seven and ten meters in length and one and two metric tons in weight.
    Sinraptorids, as briefly described earlier, were initially known as primarily Chinese LJ allosauroids, sometimes with fancy cranial ornamentation (around the turn of the century there was a hypothesis favoring extreme endemism in Chinese dinosaurs of the Jurassic, meaning that the Jurassic dinosaurs of China were thought to have been evolving on their own. This also gave us a large Euhelopodidae). They have acquired an extensive European wing as well. Allosaurids are pretty generic and best known from their namesake, the ubiquitous Morrison Formation theropod Allosaurus. Carcharodontosaurids are primarily a Gondwana "MK" radiation of very big theropods. They are a 1990s-2000s group, for the most part, because these decades have seen the first good remains from any member (some remains of Carcharodontosaurus were known in the 1930s, but were mostly scrappy and apparently destroyed in WWII) in the partial skeleton of Giganotosaurus and the skull of Carcharodontosaurus. They show some unusual convergences with the other main group of Gondwana theropods, the abelisaurids (some researchers put them together, in fact). The Neovenatoridae combines a number of odd theropods, mostly described since 1995, that have historically had very flexible placements because they do a good job of resembling coelurosaurians as well as more basal tetanurans. Derived neovenatorids, known as megaraptorans, had gracile hind legs and elongate arms, like coelurosaurians, and were generally on the small side (except for Chilantaisaurus). Neovenatoridae is a bit like the Abelisauridae of the 2000s; a sudden recognition that a bunch of previously hard-to-place theropods were related forms.
    The position of the inner ear in Acrocanthosaurus, Allosaurus, and Carcharodontosaurus indicates that instead of the traditional "jaws parallel to the ground" head pose, these theropods habitually walked with their snouts pitched down, around 25 degrees from horizontal in the case of Acrocanthosaurus.

<--Carnosauria
      |--?Siamotyrannus
      `--Allosauroidea
           |--Sinraptoridae
           |    |--+--Lourinhanosaurus
           |    |    `--Poekilopleuron
         |    `--+--Metriacanthosaurus
           |         `--Sinraptor
           `--+--Allosauridae
                |    `--Allosaurus
              `--Carcharodontosauria
                     |--Carcharodontosauridae
                     |    `--+--Eocarcharia
                     |         `--+--Acrocanthosaurus
                     |              `--+--Shaochilong
                     |                   `--+--Tyrannotitan
                     |                      `--+--Carcharodontosaurus
                     |                             |--Giganotosaurus
                     |                           `--Mapusaurus
                     `--Neovenatoridae
                          |--Neovenator
                          `--Megaraptora
                               |--Aerosteon
                               |--Australovenator
                               |--Chilantaisaurus
                               |--Fukuiraptor
                               |--Megaraptor
                               `--Orkoraptor

Carnosauria: There are a number of carnosaur-type theropods that cannot yet be placed confidently into one of the three known families, or are basal to them.

Taxon or Taxa:	Time/Place:	Comments:
Siamotyrannus isanensis Buffetaut, Suteethorn, and Tong, 1996	Barremian (EK) of Thailand	Siamotyrannus was originally described as the oldest known tyrannosaurid, but may equally well be a sinraptorid, as shown by sinraptorid-like features in the pelvis. It is known from a partial hip and some vertebrae.

Carnosauria i.s.:

Taxon or Taxa:	Time/Place:	Comments:
Erectopus superbus Huene, 1923 (originally Megalosaurus superbus Sauvage, 1882)	Albian (EK) of France	Poorly named, Erectopus appears to have been a carnosaurian of some sort. It is known from the partial skeleton of a medium-sized theropod that was thought to have a number of unusual features, but most of these appear to be in error. Part of the problem is that the original material was described fairly early in dinosaur paleontology, while another problem is that the original remains were lost in World War II, with only casts remaining.
"Poekilopleuron" valens (N.D.) Leidy, 1870	late Kimmeridgian (LJ) of Colorado	This animal, better known by its later name of Antrodemus, is based on a damaged caudal vert. It may be synonymous with Allosaurus, but there is no way to be sure.
Sigilmassasaurus brevicollis Russell, 1996	?Albian (EK) of Morocco	Based on vertebral remains from "Spinosaurus B", and possibly including the limb material, Sigilmassasaurus is an obscure theropod. It was described as having had a flexible neck with a small head, a most unusual configuration for a theropod possibly weighing more than a ton. Its describer suggested that it had short arms and was adapted for a pecking-like behavior. It may be related to the spinosaurids, although new research suggests that it is a carnosaur, not synonymous with Carcharodontosaurus as had been suggested.

Sinraptoridae: There are a number of theropods that probably belong here, but their relationships vis-à-vis Sinraptoridae's known members is not currently known. Some of this is due to poor material and some of this is due to the newness of the founding member.

Taxon or Taxa:	Time/Place:	Comments:
Lourinhanosaurus antunesi Mateus, 1998	late Kimmeridgian-Tithonian (LJ) of Portugal	This smallish (3.5-4 meters long) carnosaurian, known from a partial skeleton including verts and most of the hips and hindlimbs, is part of a Portuguese LJ fauna that has just come out over the last couple of years and includes two sauropods and Allosaurus. Eggs, embryos, and gizzard stones are also known. It has bounced between the allosauroids and megalosaurids for a while, and has currently come to rest in Sinraptoridae.
Poekilopleuron bucklandii Eudes-Deslongchamps, 1838	mid Bathonian (MJ) of France	Poekilopleuron is a bit of a paleontological tease. Its type was apparently fairly complete at one time, but lost a lot prior to collection. Later, for good measure, the rest of it was blown up in WWII, so casts are used to study it. It's a bit surprising to see it fall out as a sinraptorid, seeing as it's been put as an archetypical megalosaurid for so long.
Metriacanthosaurus parkeri Walker, 1964 (originally Megalosaurus parkeri Huene, 1926)	early-mid Oxfordian (LJ) of England	Metriacanthosaurus had fifteen minutes of fame back in the 1980s (because Greg Paul assigned Yangchuanosaurus to it) and 1990s (because the name showed up in the movie version of Jurassic Park). Otherwise, it has been very obscure, most notable for having a slight fin-back. For a short time it was considered a spinosaurid.
Sinraptor dongi Currie and Zhao, 1993 (including Yangchuanosaurus hepingensis Gao, 1992)	Oxfordian (LJ) of China	Sinraptor dongi is possibly the most boringly average large theropod now known. It doesn't even have much in the way of cranial ornamentation, like some of its compatriots. Due to bite marks on the type's skull, however, it can be guessed that these bland beasts got into tiffs with each other. Having examined the figures and the characters given to differentiate S. dongi and possible second species S. hepingensis, it is my opinion that S. hepingensis, based on a skull and partial skeleton, is most likely an individual of S. dongi, instead of a separate species. S. dongi itself is not terribly different from Yangchuanosaurus.

Sinraptoridae i.s.:

Taxon or Taxa:	Time/Place:	Comments:
Leshansaurus qianeiensis Li F., Peng G., Ye Y., Jiang S., and Huang D., 2009	Oxfordian (LJ) of China	Leshansaurus sort of snuck up on the English-speaking dinosaur research community. There's a fair amount of the beast known, including jaw and skull roof parts, verts, parts of the hand, a partial pelvis, and hindlimb, for a theropod of moderate size (6-7 m long). Hopefully it gets some more press.
Yangchuanosaurus shangyouensis Dong, Chang, Li and Zhou, 1978	Oxfordian (LJ) of China	Much more interesting than its relative Sinraptor in skull features, this theropod had a moderate finback and dual ridges running above its nasal region and eyes. It was also larger than a lot of non-carcharodontosaurid carnosaurians. I have followed the practice of Predatory Dinosaurs of the World and made Y. magnus Dong, Zhou, and Zhang, 1983 a junior synonym of the type species.

Allosauridae: Like Ceratosauridae, I'm kinda fudging on the no-monogeneric families rule. A huge Morrison New Mexican theropod, based on material from the hind end, appears to be another "super-allosaur." Ankle bones from the Albian (EK) of Australia also may be allosaurid, as well as a caudal centrum from the latest Campanian-Maastrichtian (LK) of Oman.

Taxon or Taxa:		Time/Place:	Comments:
Allosaurus: Marsh, 1877	A. fragilis (type) Marsh, 1877 (including Creosaurus atrox Marsh, 1878; Epanterias amplexus Cope, 1878)	Kimmeridgian (LJ) of western North America	Allosaurus has a long and fractured history, which I will not attempt to detail here. For the record, after a challenge from the erstwhile species Antrodemus valens (which may be seen as the name for Allosaurus in old books), Allosaurus fragilis became the accepted name for almost any kind of allosaurid remains from the Morrison Formation. Included in this is a site, known as the Cleveland-Lloyd quarry, where the disarticulated remains of over sixty individuals of Allosaurus are preserved. It is possible that the remains assigned to A. fragilis don't all pertain to one species. A. atrox has been suggested as a second valid species, but this is unlikely. That there are at least two forms of Allosaurus is shown by the differing preorbital horns of Allosaurus skulls; there are two main configurations. Whether these show two species, two sexes, part of a spectrum of different horn forms, or something else is not clear. Study of Allosaurus skulls suggests that it had a reinforced skull but a weak bite, and a very large gape. These have in turn led scientists to propose it attacked using its wide-open jaws like a spiky battleclub. Epanterias is a "super-allosaur" from the early 90s. Unlike Saurophaganax, there is no reason to think that it's anything other than a really big A. fragilis.
Allosaurus: Marsh, 1877	A. europaeus Mateus, Walen, and Telles-Antunes, 2006	late Kimmeridgian-early Tithonian (LJ) of Portugal	This species of Allosaurus is based on a partial skull that is very similar to that of A. fragilis, and may just be the same species. Other Portuguese material may also be referable to this carnosaur, including verts, ribs, and pelvic and hindlimb material.

Allosauridae i.s.:

Taxon or taxa:	Time\Place	Comments:
?"Allosaurus" tendagurensis (N.D.) Janensch, 1925	Kimmeridgian (LJ) of Tanzania	This animal cannot be proven to be a species of Allosaurus, but remains from Tendaguru indicate the presence of allosaurids. Alternatively, it could be a basal tetanuran, and/or related to the dubious EK "Elaphrosaurus" species.
Saurophaganax maximus Chure, 1995	Kimmeridgian (LJ) of Oklahoma	This taxon is a monstrously large allosaurid. By monstrously large, I mean an animal in the five metric ton size range. It's based on partial material from four individuals collected and prepped by WPA workers during the Depression. It was known informally as "Saurophagus" (Ray, 1941) for many years, during which it spent some time mixed up with Acrocanthosaurus because an author mistakenly thought it was from the Cretaceous.

Carcharodontosauridae: The skulls of carcharodontosaurids are narrow, long, and in some ways resemble scissors. Several (Carcharodontosaurus, Eocarcharia, Giganotosaurus, and Mapusaurus) bear reinforced bone over the eyes, indicating a possible function in physical actions against other carcharodontosaurids. Carcharodontosaurid material is turning up all over Africa and South America, including a possible 12-13 meter long animal from the Cenomanian (LK) of Argentina known from remains of two individuals, and a Turonian (LK) specimen, also from the same country. Tyrannotitan and Mapusaurus may be united with Giganotosaurus in "Giganotosaurinae." Late Cretaceous teeth from Argentina, thought to be from carcharodontosaurids, probably came from abelisaurids instead.

Taxon or Taxa:		Time/Place:	Comments:
Eocarcharia dinops Sereno and Bruasatte, 2008		Aptian-Albian (EK) of Niger	Eocarcharia is a carcharodontosaurid from the Acrocanthosaurus wing of the family, except with a strongly ornamented postorbital. It's known from skull bones, mostly the maxilla and the stuff behind the eyes. It was smallish as these things go, in the 6 to 8 m long range.
Acrocanthosaurus atokensis Stovall and Langston, 1950		Aptian-Albian (EK) of Oklahoma, Texas, Utah, Arizona, and Maryland	Acrocanthosaurus is one of my favorite dinosaurs. It is most famous for its tall vertebral spines, and has specimens reaching sizes like those of large tyrannosaurids. Recently, more material has turned up, including a virtually complete skull and skeleton, and shed a lot of light on this late carnosaur. An animal very similar to Acrocanthosaurus, if not one and the same, produced some of the famous Paluxy River dinosaur tracks in Texas, including a sequence where an individual appears to pursue a large Pleurocoelus (or Astrodon)-type sauropod. Although not known directly from the Cloverly, it is considered to be a contemporary of that fauna. Interestingly, its neck seems to have been straighter than most theropods, possibly as an alternative solution to holding up a large head. The skull, in gross form, appears to mostly closely resemble that of Carcharodontosaurus, but is not too different from Allosaurus as well.
Shaochilong maortuensis Brusatte, Benson, Chure, X. Xu, Sullivan, and Hone, 2009 (originally Chilantaisaurus maortuensis Hu, 1964)		Turonian (LK) of China	Shaochilong spent many years as the second species of Chilantaisaurus, then was in limbo for about a decade. While the fact that it wasn't Chilantaisaurus was known for a while, what exactly it was instead wasn't, with some sort of basal coelurosaurian, perhaps on the tyrannosauroid line, being kicked about before its redescription as a carcharodontosaurid. It becomes Asia's first carcharodontosaurid and the latest named carcharodontosaurid. So far it is known only from skull bones and a few verts.
Tyrannotitan chubutensis Novas, de Valai, Vickers-Rich, and Rich, 2005		Aptian (EK) of Argentina	Just coming out is this carcharodontosaurid, described as being more basal than Carcharodontosaurus or Giganotosaurus. It is known from two individuals, with the type including partial dentaries, some vertebrae and ribs, partial scapulacoracoid and arm, a good chunk of the pelvis, and a femur, fibula, and metatarsal, and the other individual overlapping these remains. It seems to have been robust and at least slightly smaller than Giganotosaurus, but with a similarly squared-off dentary tip.
Carcharodontosaurus: Stromer, 1931	C. saharicus (type) (originally Megalosaurus saharicus Deperet and Savornin, 1927)	Albian-Cenomanian (EK-LK) of Morocco, Algeria, and Egypt	This taxon was named from some shark-like teeth. Later, skull material with such teeth in their sockets turned up. Unfortunately, the early material has either been lost or destroyed in World War II. Most recently, a very large, nearly complete skull has turned up. Carcharodontosaurus saharicus is synonymous with Megalosaurus africanus (N.D.) Huene, 1956, although apparently not with Stromer's "Spinosaurus B" material, including the holotype of Sigilmassasaurus (as has been suggested).
Carcharodontosaurus: Stromer, 1931	C. iguidensis Brusatte and Sereno, 2007	Cenomanian (LK) of Niger	C. iguidensis is known largely from cranial remains from a few individuals of different skeletal maturity. You may remember lead author Steve Brusatte from the now-extinct Official Dino Land Website.
Mapusaurus roseae Coria and Currie, 2006		Cenomanian (LK) of Argentina	One of the most beloved "public domain dinosaurs," this is the famous "group carcharodontosaurid" that has been floating around for a while. This is also, as far as I know, the same as the "phantom spinosaur" "Mupasaurus" created on the Internet on the basis of misinterpreted rumors of giant, soon-to-be-published Argentine and African "MK" theropods; don't believe everything you read on the Internet! At some points, it had also been rumored as a second species of Giganotosaurus. Well, here it is, so knock off the rumors. The actual animal is known from a bonebed of at least seven individuals, maybe up to nine, of different sizes from 5 to 12 m long (the latter in Giganotosaurus's range). It was close to Giganotosaurus, but with a deeper and narrower skull. Why several individuals were found together is not known, although the paper suggests that it was intentional on the part of the animals.
Giganotosaurus carolinii Coria and Salgado, 1995		Cenomanian-early Turonian (LK) of Argentina	Like Carcharodontosaurus a rival to Tyrannosaurus rex in size (probably longer and heavier by a shade), this taxon is known from a partial skeleton and skull, with a squared-off rostral end to the lower jaw in lateral view. It may have hunted the huge contemporary titanosaurians. New fossil remains, including that of a "family," may pertain to it or to a close relation. A new dentary suggests an individual somewhat larger than the type.

Neovenatoridae:

Taxon or Taxa:	Time/Place:	Comments:
Neovenator salerii Hutt, Martill, and Barker, 1996	Barremian (EK) of England	Neovenator is based on a rather pathologic partial skeleton and skull including material from the main divisions of the skeleton except the forelimbs, and was originally informally called a megalosaur. It appears to have had a tall, puffin-like snout. The type individual may have been around 7 meters in length, but material from another individual suggests lengths of up to around 10 meters.
Aerosteon riocoloradensis Sereno, Martinez, Wilson, Varricchio, Alcober, and Larrson, 2008	Santonian (LK) of Argentina	Aerosteon is a tetanuran of neovenatorid affinities, roughly 9 to 10 m long (30-33 ft or so) as a nearly grown immature animal. It is based on most of the front end of a skeleton, including a few skull bones, most of the neck and trunk, a shoulder girdle with furcula, and a partial pelvis. Parts of the distal legs are also known. Of course, the interesting thing about it is that it seems to have come from a heretofore unknown lineage... (which has turned out to be Neovenatoridae) well, yeah, that's interesting, but the thing about this beast that's been leading the headlines is its pneumaticity, including bird-like pneumatic ilia and furcula.
Australovenator wintonensis Hocknull, White, Tischler, Cook, Calleja, Sloan, and Elliott, 2009	latest Albian (EK) of Australia	Remember that old "Allosaurus sp." thing, that astragalus from Australia that was taken as evidence for a dwarf mid-Cretaceous Australian Allosaurus? It was probably something like this animal (if not the same). So just what is this? Australovenator has some things in common with Fukuiraptor, and other things in common with carcharodontosaurids. It is known from much of the arms and legs, a partial lower jaw, some gastralia and ribs, and an ilium.
Chilantaisaurus tashuikouensis Hu, 1964	Turonian (LK) of China	This animal is poorly known, but apparently had whopping big claws and hands. It's long been popular as an obscure theropod, and has spent time as an allosaurid, transitional allosaurid-tyrannosaurid, and basal tetanuran, among others.
Fukuiraptor kitadaniensis Azuma and Currie, 2000	Albian (EK) of Japan	This smallish carnosaurian may have been known for many years under the guise of "Kitadanisaurus", supposedly a large dromaeosaurid. The type remains, from an immature individual, include a maxilla, dentary, teeth, a dorsal, a caudal, much of the forelimbs (with large claws) and a leg, and most of a hip. It may be synonymous with every unofficially-named Japanese theropod starting with the letter "K".
Megaraptor namunhuaiquii Novas, 1998	Coniacian (LK) of Argentina	As its name implies, this was first thought to be a very large "raptor"-type dinosaur. Additional remains put the claws, still quite impressive, on the hands. It proved frustrating for a number of years because it didn't fall neatly into any more derived theropod groups. As it turned out, that because it wasn't part of any lineage understood at the time.
Orkoraptor burkei Novas, Ezcurra, and Lecuona, 2008	Maastrichtian (LK) of Argentina	Orkoraptor is a largish theropod (6-7 m long). Like the other members of Neovenatoridae, it didn't fit the usual suspects of its time and place, in its case LK Argentina (abelisauroid, carcharodontosaurid, alvarezsaurid, or deinonychosaurian). Unfortunately, it's known from fragmentary remains at this point, including skull bits and teeth, a partial cervical and two caudals, ribs and chevrons, and a tibia.

Megaraptora i.s.:

Taxon or Taxa:	Time/Place:	Comments:
Rapator ornitholestoides Huene, 1932	Albian (EK) of Australia	Rapator gets around. It was originally described from an unusual "metacarpal" that bore some resemblance to that of Ornitholestes. Since then, it has bounced between the "carnosaurs," allosaurids, abelisaurids, "ornitholestids" and other basal coelurosaurians, and, most interestingly, alvarezsaurids (with the metacarpal as a phalange of the strong single finger).

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