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: Metriacanthosauridae (formerly 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.
    Metriacanthosaurids 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). 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 (possibly tyrannosauroids instead, but what the heck), 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
      |--Allosauroidea
      `--+--Metriacanthosauridae
           |    |--Yangchuanosaurus
           |    `--+--Shidaisaurus
           |         `--+--"Yangchuanosaurus" hepingensis
           |              `--+--Metriacanthosaurus
           |                   `--+--Siamotyrannus
           |                        `--Sinraptor
           `--+--Allosauridae
                |    |--Allosaurus
                |    `--Saurophaganax
                `--Carcharodontosauria
                     |--Carcharodontosauridae
                     |    |--+--Concavenator
                     |    |    `--Eocarcharia
                     |    `--+--Acrocanthosaurus
                     |         `--+--Shaochilong
                     |              `--+--Carcharodontosaurus
                     |                   |--Tyrannotitan
                     |                   `--+--Giganotosaurus  
                     |                        `--Mapusaurus 
                     `--Neovenatoridae
                          |--Neovenator
                          `--+--Chilantaisaurus
                               `--?Megaraptora
                                      |--Siats
                                      `--+--+--Australovenator
                                           |    `--Fukuiraptor
                                           `--Megaraptoridae
                                                |--Aerosteon
                                                `--Megaraptor

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

Taxon or Taxa: Time/Place: Comments:
?"Allosaurus" medius (N.D.) Marsh, 1888 late Aptian-early Albian (EK) of Maryland "A." medius is based on a tooth that has been allied to Allosaurus (well, obviously) and Dryptosaurus, but is probably from something like Acrocanthosaurus, if not the same thing.
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. It may have been a metriacanthosaurid.
"Megalosaurus" ingens (?N.D.) Janensch, 1920 Kimmeridgian (LJ) of Tanzania This theropod is based on a whopping big and distinctive tooth, suggesting an owner that weighed around five metric tons. Sometimes thought to be a species of Ceratosaurus, it may be a carcharodontosaurid instead.
"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.

Metriacanthosauridae: No longer are sinraptorids just for a small slice of time in east Asia – you can now enjoy them in Europe as well! Of course, we had to change the name (rules of priority and whatnot), but we think you'll like them just as much as metriacanthosaurids.

Taxon or Taxa: Time/Place: Comments:
Yangchuanosaurus:  Dong, Chang, Li and Zhou, 1978  Y. shangyouensis (type) Dong, Chang, Li, and Zhou, 1978 (includes Y. magnus Dong, Zhou, and Zhang, 1983, and probably CV 00214) 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.
Yangchuanosaurus shangyouensis may include the headless specimen known variously as CV 00214, [redacted because it has never been officially published, but not that hard to find], "Szechuanosaurus yandonensis", or, from Predatory Dinosaurs of the WorldMetriacanthosaurus sp. (or M. carpenteri if you were really paying attention). It is not the same as "S." zigongensis, which comes from older rocks and is morphologically distinct.
Y. zigongensis (Gao, 1993 [originally Szechuanosaurus]) Bathonian-Callovian (MJ) of China Y. zigongensis is based on a partial headless skeleton which was initially referred to Szechuanosaurus, a genus based on teeth. This may seem counterintuitive, but it was apparently done on the basis of a maxilla with teeth that had been referred to zigongensis. "Well, okay", you say, "but there was still no overlapping material between the skeleton and the skull fragment," to which... uh, look out behind you! <runs away>
Theropod teeth being what they are, Szechuanosaurus proper is not all that useful, but this skeleton and assorted referred postcranial material are.
Shidaisaurus jinae Wu X., Currie, Dong Z., Pan S., and Wang T., 2009 early MJ of China Shidaisaurus is a tetanuran of uncertain affinities based on a partial skull and skeleton (lacking the tail, most of the limbs, and the pectoral girdle) with the poor luck to be partly covered by a sauropod.
"Yangchuanosaurus" hepingensis Gao, 1992 Oxfordian (LJ) of China Having examined the figures and the characters given to differentiate Sinraptor dongi and this species, commonly given as possible second species S. hepingensis, it is my opinion that there isn't a whole lot to differentiate hepingensis (based on a skull and partial skeleton) from dongi. However, it does come from a different formation, which is reasonable grounds to keep them separate until detailed review. S. dongi itself is not terribly different from Yangchuanosaurus.
Metriacanthosaurus parkeri Walker, 1964 (originally Megalosaurus parkeri Huene, 1926) early 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.
Siamotyrannus isanensis Buffetaut, Suteethorn, and Tong, 1996 Barremian-Aptian (EK) of Thailand Siamotyrannus was originally described as the oldest known tyrannosaurid, but may equally well be a metriacanthosaurid, as shown by similar features in the pelvis. It is known from a partial hip and some vertebrae.
Sinraptor dongi Currie and Zhao, 1994 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.

Allosauridae:  A huge Morrison New Mexican theropod, based on material from the hind end, appears to be another "super-allosaur."  A caudal centrum from the latest Campanian-Maastrichtian (LK) of Oman may be allosaurid (or just generally large theropod, because Allosaurus has long been a standard of comparison for theropods).

Taxon or Taxa: Time/Place: Comments:
Allosaurus: Marsh, 1877 A. fragilis (type) Marsh, 1877 (including Creosaurus atrox Marsh, 1878; Epanterias amplexus Cope, 1878; Allosaurus lucasi Dalman, 2014) 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.
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.
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.

Carcharodontosauria i.s.:

Taxon or Taxa: Time/Place: Comments:
Datanglong guangxiensis Mo J., Zhou F., Li G., Huang Z., and Cao C., 2014 EK of China Datanglong is an Allosaurus-scale theropod known from the posteriormost dorsal, the sacrum, a couple of caudals, an ilium, and bits of other pelvic bones.
Kelmayisaurus petrolicus Dong, 1973 ?Valanginian-Albian (EK) of China This obscure Allosaurus-sized theropod is based on parts of the upper and lower jaws, which have been described as being like those of Ceratosaurus, but are from a tetanuran instead. It seems to be a basal carcharodontosaurian. A possible second, undescribed species is supposedly very long, but may not actually exist (possibly a misidentified sauropod).

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:
Concavenator corcovatus Ortega, Escaso, and Sanz, 2010 late Barremian (EK) of Spain The spring and summer of 2010 had already been a festival of horned dinosaurs when the overbuilt dromie Balaur was published and seized media attention, only to cede it to a larger European theropod. Concavenator just goes to show that there are always new weird things out there, in this case an otherwise fairly normal theropod that had evolved a mini-billboard just in front of its hips, through a pair of exaggerated dorsal vert neural spines.
Concavenator also has seen more than its share of paleontological intrigue. It was described as possibly possessing quill nodes on its forearms, which are attachment points for feathers, and restored with the Cretaceous version of a fringed jacket. Other commentators have pointed out that the nodes could also trace muscle attachments. Then, it was pointed out that there was already a set of unusually tall theropod vertebrae from the EK of Europe, namely the three verts formerly known as Altispinax and presently known as Becklespinax. Of course, Concavenator is known from most of a skeleton with scale impressions while Becklespinax is known from three verts that had spent most of the past century and a half incorrectly over the shoulders of an otherwise hypothetical megalosaur. Upon further review, it turned out that the two genera were actually distinct (for one thing, Becklespinax proved to be more mysterious and obstinate than previously thought by refusing to sort out as either a spinosaurid or a carcharodontosaurid), but you have to admit it's a heck of a coincidence that there were two theropods in the EK of Europe that had a restricted lumbar billboard.
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 late Aptian-middle Albian (EK) of Oklahoma, Texas, and Wyoming; probable Acrocanthosaurus material in 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. 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. 
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 apparently not synonymous with Stromer's "Spinosaurus B" material or the holotype of Sigilmassasaurus (as has been suggested).
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.
Tyrannotitan chubutensis Novas, de Valai, Vickers-Rich, and Rich, 2005 Aptian-Albian (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 scapulocoracoid 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.
Giganotosaurus carolinii Coria and Salgado, 1995 late? Cenomanian (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.
Mapusaurus roseae Coria and Currie, 2006 Turonian-Santonian (LK) of Argentina One of the most beloved "public domain dinosaurs," this is the famous "group carcharodontosaurid" that was 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 nine individuals, ranging from roughly 5 to 11 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.

Carcharodontosauridae i.s.:

Taxon or Taxa: Time/Place: Comments:
Sauroniops pachytholus Cau, Dalla Vecchia, and Fabbri, 2012 Cenomanian (LK) of Morocco (probably; provenance not known for certain) The first nonavian dinosaur named by allusion to Tolkien, Sauroniops appears to have been a basal carcharodontosaurid, akin to Eocarcharia. It is known only from a thick frontal bone (part of its skull roof, above the eyes).
?Unquillosaurus ceibalii Powell, 1979 late Santonian-?Campanian (LK) of Argentina It is not certain where this theropod belongs. It is based on a pubis that appears to show opisthopuby, although this is based on a long-time interpretation of the bone as a right pubis when it may actually be a left pubis. When the type specimen is described as a right pubis, Unquillosaurus has been classified most recently as a large unenlagiine-like dromaeosaurid, but as a left pubis it appears to have been a carcharodontosaurid. It may be the same as another already-named theropod for which the pubis is unknown.
Veterupristisaurus milneri Rauhut, 2011 late Kimmeridgian-early Tithonian (LJ) of Tanzania Veterupristisaurus adds a carcharodontosaurid to the Tendaguru assemblage. It is based on a caudal vertebra, with a few other caudals referred to it, and may be closely related to Acrocanthosaurus.

Neovenatoridae:

Taxon or Taxa: Time/Place: Comments:
Neovenator salerii Hutt, Martill, and Barker, 1996 late Hauterivian-early 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. 
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.
Siats meekerorum Zanno and Makovicky, 2013 early Cenomanian (LK) of Utah Siats holds, for the time being, the position of the most recent carnosaurian in North America (as long as megaraptorans were not tyrannosauroids, of course), having taken the spot from Acrocanthosaurus. It is known from material including a few dorsals and caudals, part of the right pelvis, a fibula, a partial tibia, and toe bones, all from a partially grown individual. A fully-grown individual would have been comparable to an adult Acro in size. The name refers to a monster in Ute mythology.
Australovenator wintonensis Hocknull, White, Tischler, Cook, Calleja, Sloan, and Elliott, 2009 Cenomanian-Turonian (LK) 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.
Fukuiraptor kitadaniensis Azuma and Currie, 2000 Barremian (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.
Aerosteon riocoloradensis Sereno, Martinez, Wilson, Varricchio, Alcober, and Larrson, 2008 early Campanian (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. 
Megaraptor namunhuaiquii Novas, 1998 late Turonian-early 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.  

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).
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 dromaeosaurid). 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.

 

Navigation
Home Page Alphabetical Dinosaur Index Clado-Index
Background Information Glossary Faunae