Tetanurae

    Tetanurae includes both birds and the more advanced classic theropods. It has three major groups: Megalosauroidea, Carnosauria and Coelurosauria. All tetanurans have gained a strap-like scapula, have no maxillary teeth posterior to the eyes in lateral view, have an extra hole in the skull between the nasal opening and the antorbital opening, have an obturator process on the ischium, and a number of other characters. New early tetanurans include a partial skeleton from the middle Sinemurian (EJ) of Italy that preserves a furcula.

<--Tetanurae
      |--Chuandongocoelurus
      |--Monolophosaurus
      `--+--Megalosauroidea
           |    |--Piatnitzkysauridae
           |    |    |--Marshosaurus
           |    |    `--+--Condorraptor
           |    |         `--Piatnitzkysaurus
           |    `--+--Megalosauridae
           |         |     |--Eustreptospondylus
           |         |     `--+--+--Duriavenator
           |         |          |    `--+--Megalosaurus        
           |         |          |         `--Torvosaurus
           |         |          `--+--Afrovenator
           |         |               `--+--+--Dubreuillosaurus
           |         |                    |     `--Magnosaurus
           |         |                    `--+--Leshansaurus
           |         |                         `--Piveteausaurus
    
      |         `--Spinosauridae
           |              |--Baryonychinae
           |              |    |--Baryonyx
           |              |    `--Ichthyovenator
           |              `--Spinosaurinae
           |                   |--Irritator
           |                   `--+--Oxalaia
           |                        `--Spinosaurus
           `--Avetheropoda
                |-->Carnosauria
                `-->Coelurosauria

Tetanurae:

Taxon or Taxa: Time/Place: Comments:
Chuandongocoelurus primitivus He, 1984 Bathonian-Callovian (MJ) of China Rather obscure, Chuandongocoelurus is based on a partial skeleton, probably chimeric as the presacral verts appear to be too large for the rest of the skeleton, of a subadult individual. It may be a basal tetanuran, or close to Elaphrosaurus.
Monolophosaurus jiangi Zhao and Currie, 1994 Callovian (MJ) of China Monolophosaurus, also known by its informal name "Jiangjunmiaosaurus", is known from a partial skeleton and skull that defies description in its head crest, a laterally-compressed ridge running from its nose to the rear of the skull. The skull is also amazingly narrow in front view; this may, however, be a result of compression.

Tetanurae i.s.:  Most of these are either some sort of basal tetanuran or too poor for classification, or both. There is a possible basal tetanuran in the Coniacian-Santonian (LK) of Antarctica, described as being of Coelophysis-size.

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. Actual "A." tendagurensis , based on a tibia, can only be assigned to Tetanurae. It appears to be a large, basal tetanuran, and/or related to the dubious EK "Elaphrosaurus" species.
Becklespinax altispinax Olshevsky, 1991 (originally Acrocanthosaurus altispinax Paul, 1988) Berriasian-Valanginian (EK) of England Becklespinax is based on the three high-spined vertebrae (actually, only the last two have preserved high spines; either something happened to the first vert, or it didn't have a high spine) that were at one time combined with a Megalosaurus tooth species to produce Altispinax dunkeri. This link has been shown to be unjustified, and a new name was required for the distinctive vertebrae (although there are some knotty nomenclatural problems here).
Classically, Altispinax was restored with a sort of hump over its shoulders, on the assumption that the high spines went there. There is a long story behind this: the vertebrae were first found very early in the history of dinosaur study, back when dinosaurs were thought to be elephantine quadrupeds. In an understandable turn of events, the verts were speculated to have been in the shoulder region of quadrupedal Megalosaurus, putting one in mind of withers. When it was later shown that Megalosaurus and related dinosaurs were bipeds, the shoulder hump remained.
It has become clear that theropods had more than one trick to play with elongated neural spines. The discovery of Concavenator provides an example of a theropod with two high-spined vertebrae just before the hips, and the discovery of Ichthyovenator provides an example of a double-finned theropod, with a distinct fin over the dorsals and another over the sacrum. Becklespinax's fin could have been in the mold of either of these genera, or something different; it doesn't appear to have been either a carcharodontosaurid or spinosaurid.
"Calamospondylus" foxi (N.D.) Lydekker, 1889 (Calamosaurus) Barremian (EK) of England Also known as Calamosaurus, this small theropod is based on two cervical vertebrae and an unusual referred tibia. It can be assigned no higher than Tetanurae, but may be a basal coelurosaurian or basal tyrannosauroid, because its cervicals are similar to those of Dilong.
Cruxicheiros newmanorum Benson and Radley, 2009 early Bathonian (MJ) of England Cruxicheiros is a basal tetanuran, based on a femur but with a few other bones probably from the same individual (parts of at least four verts, a partial scapulocoracoid and ilium, the end of pubis, and fragments).
Iliosuchus incognitus (N.D.) Huene, 1932 mid Bathonian (MJ) of England Iliosuchus is based upon two very small ilia that have a vertical ridge on the outside surface. This is similar to the condition in tyrannosauroids, and for a time Iliosuchus was mooted as an early tyrannosauroid, and perhaps congeneric with Stokesosaurus. However, the feature is more widely distributed, and Iliosuchus could also be just juvenile examples of Megalosaurus.
Kaijiangosaurus lini He, 1984 (?Gasosaurus) Bathonian-Callovian (MJ) of China Like its contemporary (?synonym) Gasosaurus, Kaijiangosaurus doesn't fit the established groups particularly well. It may be somewhere near the ancestry of Carnosauria. Unfortunately, both are obscure. A femur included in the type appears to be too small to belong.
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 has long been an archetypical megalosaurid, but now shows up in a variety of places in analyses.
Sciurumimus albersdoerferi Rauhut, Foth, Tischlinger, and Norell, 2012 LJ of Germany Sciurumimus is known from a complete skeleton of a young juvenile with filament-like feathers, including a bushy squirrel-like tail (but if you are familiar with scientific names, you probably already figured there was something squirrel-like about it). It was described as a megalosauroid, but it more likely a basal coelurosaurian, although you never can quite tell with the very young specimens. In either case, it would probably be close to the base of the lineage, which makes it even more difficult hard to tell.
"Streptospondylus" cuvieri (N.D.) Owen, 1842 Aalenian-Bajocian (MJ) of England This dubious species of Streptospondylus is based on a partial dorsal vertebra, and let no one else tell you otherwise!
Xuanhanosaurus qilixiaensis Dong, 1984 Bathonian-Callovian (MJ) of China This theropod is unusual in its heavily-built forelimb, an attribute which has led some workers to suggest it was quadrupedal (extremely unlikely), and has led others to suggest megalosaurid affiliations. It had four fingers and possibly a clavicle, which is rarely preserved in dinosaurs.

Basal Megalosauroidea (now featuring Piatnitzkysauridae): In general, basal megalosauroids and megalosaurids are known for their long, low builds and short, stout arms. Because of the Continuing Adventures of Megalosaurus bucklandi, the names Megalosauroidea and Spinosauroidea, and Megalosauridae and Torvosauridae, switch back and forth on an enjoyably rhythmic basis as Megalosaurus is considered dubious or valid. Of course, if it is established that there is no real close relationship here, these taxa all revert to basal Tetanurae. A recently-discovered 50-foot long German theropod may be related.

Taxon or Taxa: Time/Place: Comments:
Marshosaurus bicentesimus Madsen, 1976 Kimmeridgian (LJ) of Utah and Colorado Something of an enigma, Marshosaurus has features that are reminiscent of coelophysoids, coelurids, metriacanthosaurids, and allosaurids, all wrapped up in a pelvis! The specific name, I assume, refers to the USA's bicentennial year 1976, the same year that this species was described. A number of other remains have been referred to this taxon, including a partial skeleton first found in 1912. This material shows a short-armed animal, probably a fairly basal carnosaur, if not closer to megalosaurids.
Condorraptor currumili Rauhut, 2005 Aalenian-Bathonian (MJ) of Argentina Condorraptor, based on a partial tibia, was a mid-sized (4-5 m long) basal tetanuran. No features that would support assignment to a more derived group have been found, so it appears that this animal will stay with the basal tetanurans. Referred to it are associated bonebed remains that appear to derive from a single individual: a partial postcranial skeleton including a partial hind limb, pelvis, and assorted vertebrae.
Piatnitzkysaurus floresi Bonaparte, 1979 Aalenian-Bathonian (MJ) of Argentina This animal has one of the least spellable names in dinosaurdom, right up there with Opisthocoelicaudia. It is known from a couple of partial skulls and skeletons (with unusually robust arms), and is important both for the location and time it lived in, as few Jurassic South American dinosaurs are known. There may be a relationship with Becklespinax (no, not that kind of relationship, you sickos!).

Megalosauroidea i.s.:

Taxon or Taxa: Time/Place: Comments:
Streptospondylus altdorfensis Meyer, 1832 late Callovian or early Oxfordian (MJ or LJ) of France This theropod appears to be related to Eustreptospondylus. There's a number of synonyms related to this taxon, and I'm not sure of all of them yet (Streptospondylus is one of those taxa where taxonomic angels fear to tread). Its material includes a fair number of verts (mostly dorsals), a partial pubis, and parts of bones from the right ankle and shank.

Megalosauridae: Megalosauridae, and Megalosaurus for that matter, used to be a major dumping ground for theropods which were inadequately known. Part of this stemmed from historical precedent (Megalosaurus was the first named classic theropod), part of this stemmed from the fact Megalosaurus is not based on the clearest of remains, and part of this stemmed from the fact that what is known of Megalosaurus suggests it was a fairly average big theropod. It has been cleaned up a great deal, though.

Taxon or Taxa: Time/Place: Comments:
Eustreptospondylus oxoniensis Walker, 1964 late Callovian (MJ) of England Also originally under the Megalosaurus umbrella, the partial skull and skeleton that make up the type of this species were later shown to be distinct from Megalosaurus. This theropod is blessed with one of the most convoluted names in dinosaur paleo.
Duriavenator hesperis Benson, 2008 (originally Megalosaurus hesperis Waldman, 1974) late Bajocian (MJ) of England This animal is based on a partial skull, the lower jaw of which is similar to that of Megalosaurus. It has also been known under the nomen nudum "Walkersaurus".
Megalosaurus bucklandii Buckland, 1824 (species after Mantell, 1827) early mid Bathonian (MJ) of England The prototypical "big theropod" and the first classic dinosaur to be named (almost; there are two pre-Linnean names for what are now known to be dinosaur fossils, one a sauropod tooth named "Rutellum implicatum" in 1699, the other the colorfully-named "Scrotum humanum" of 1763 [long story, but an allusion to the shape of the bone became amplified into the petrified personal region of a giant and then became a quasi-scientific name], for a femur end that pertained to something like Megalosaurus if not that genus; usually we only count Megalosaurus Buckland, 1824 because his guess was closer to what it really was), Megalosaurus is based on a dentary, which limits comparison to other taxa, although much or all the material found from its type locality that is theropod may belong to the type. Many elements have been referred to it.
Torvosaurus Galton and Jensen 1979  T. tanneri (type) Galton and Jensen, 1979
(including Edmarka rex Bakker, Kralis, Siegwarth, and Filla, 1992, and "Brontoraptor" Redman, 1995)
Kimmeridgian (LJ) of Colorado and Wyoming Forget cheap little Allosaurus—this critter was built to take it!  From what is known, including partial forelimb, pelvis, and skull, this animal was larger and more heavily built than its famous Morrison Formation contemporary (well, at least A. fragilis). It is almost certainly the senior synonym of the big megalosaurid Edmarka rex. The skull is long and low.
T. gurneyi Hendrickx and Mateus, 2014 late Kimmeridgian (LJ) of Portugal T. gurneyi represents the Portuguese species of this animal. It is based on a maxilla. A variety of miscellaneous bones are thought to have come from it, as well as eggs and embryoes. At this time, it is the largest theropod known from Europe. 
Afrovenator abakensis Sereno, Wilson, Larsson, Dutheil, and Sues, 1994 sometime between the Late Triassic and Aptian, perhaps MJ of Niger Afrovenator is based on most of a skeleton and skull that show it to have been a fairly typical theropod.
Dubreuillosaurus valesdunensis Allain, 2005 (originally Poekilopleuron? valesdunensis Allain, 2002) mid Bathonian (MJ) of France This megalosaurid is known from an excellent skull and partial postcranium that establish it is not Poekilopleuron, which is too bad, because Poekilopleuron is kinda fun to say. The story of assembling the postcranial skeleton sounds like a living hell: the specimen was found in an abandoned quarry, and the skull was removed. When paleontologists went back to get the rest of it, they found that the quarry had been reopened, and the skeleton turned into over 2000 centimeter-scale fragments, which depressingly seems par for the course with European-discovered-or-curated theropods (see the types of Poekilopleuron, Spinosaurus, Carcharodontosaurus, and Bahariasaurus, or rather, don't, as they were all blown up in World War II). Cervicals, dorsals, sacrals, caudals, chevrons, ribs, scapulae, hindlimb, and etcetera are known in part from the postcranium.
Magnosaurus nethercombensis Huene, 1932 (originally Megalosaurus nethercombensis, Huene 1926) early Bajocian (MJ) of England This fragmentary theropod labors in obscurity, although for a brief period it was though to be the senior synonym of Eustreptospondylus ("Oh, and once I saw a blimp!").
Leshansaurus qianeiensis Li F., Peng G., Ye Y., Jiang S., and Huang D., 2009 Oxfordian (LJ) of China Originally described as a sinraptorid (metriacanthosaurid), 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.
Piveteausaurus divesensis Taquet and Welles, 1977 (originally Eustreptospondylus divesensis Walker, 1964) late Callovian (MJ) of France This genus is based on a braincase that may pertain to an animal similar to Piatnitzkysaurus. Otherwise, it is rather obscure. For a time, it was thought to be an "ornitholestid" related to Proceratosaurus.

Spinosauridae: The spinosaurids were long predators with elongated vertebral spines and crocodile-like jaws with specialized unserrated teeth. Fish probably formed part of their diet. Ironically, a taxon that is probably a marine creature, Asiamericana, has been classified as a spinosaurid at times. Several members are known to have had vertebral fins, although Spinosaurus so far is the champ by height. Some restorations of spinosaurids show them as quadrupedal, a mistake based on early descriptions of the arms of Baryonyx.
    There is apparently another spinosaurid in the Aptian-Albian (EK) of Brazil, but it is as yet undescribed. It is known from a sacrum, caudals, pelvic material, and partial limbs.

Taxon or Taxa: Time/Place: Comments:
Baryonyx:
Charig and Milner, 1986 (including Suchomimus Sereno et al., 1998) (?Suchosaurus)
B. walkeri (type) Charig and Milner, 1986 Barremian-early Aptian (EK) of England and Spain This animal is known from most of a skull and skeleton of a subadult individual. First nicknamed "Claws" from its huge claws, and before description considered a possible giant dromaeosaurid, this spinosaurid may have also lived in the Aptian of Niger (although whether all the material belongs to the type species remains to be seen). It was probably a fisher or scavenger at least in part, and is likely the same thing as the old tooth/jaw taxon Suchosaurus.
?B. tenerensis (Sereno, Beck, Dutheil, Gado, Larsson, Lyon, Marcot, Rauhut, Sadleir, Sider, Varricchio, G. Wilson, and J. Wilson, 1998 [originally Suchomimus])  Aptian (EK) of Niger This theropod is based on most of a skeleton and skull, which is very long and crocodile-like. From the end of it points a whole lot of very long, pointy teeth. The type, although very large, may belong to a partially-grown individual. There is little to distinguish it from B. walkeri, so I've decided to go along with some other current opinions and tentatively assign it to Baryonyx.
?Ichthyovenator laosensis Allain, Xaisanavong, Richir, and Khentavong, 2012 ?Aptian (EK) of Laos Ichthyovenator is known from a partial postcranial skeleton, comprising a chunk of the body from the area of the hips (a couple of dorsals and caudals, the sacrals, most of the pelvis, and a rib). Interestingly, its sail does not present a smooth profile, but falls off at the end of the dorsal vertebrae, then rises again over the sacrum.
Irritator challengeri Martill, Cruickshank, Frey, Small, and Clarke, 1996 (including Angaturama limai Kellner and Campos, 1996) Albian (EK) of Brazil The unusual name of this spinosaurid stems from the fact the type skull was both damaged and artificially lengthened by amateur fossil hunters before it was described. The skull hardly needed it; as a spinosaurian skull, it is strange enough without amplification. Angaturama, another unusual theropod from the same formation, is probably a junior synonym of Irritator, and could possibly be part of the holotype specimen.
60% of a skeleton referred to Angaturama is now known.
Oxalaia quilombensis Kellner, Azevedeo, Machado, Carvalho, and Henriques, 2011 Cenomanian (LK) of Brazil Oxalaia is a large (12-14 m scale) spinosaurid. It was named from a section of fused premaxillae, with a referred partial maxilla.
Spinosaurus aegyptiacus Stromer, 1915 (?including Sigilmassasaurus brevicollis and Spinosaurus maroccanus, both Russell, 1996; synonymy questionable at the species level) Albian-Cenomanian (EK-LK) of Egypt, Morocco, and ?Tunisia The most famous fin-back, Spinosaurus has come out of a period when it was considered to resemble a tyrannosaurid with fin attached. Its main remains were lost in WWII, but pointed to an animal closing in on 45-50 feet in length with vertebral spines taller than a human. Since that time, a variety of other partial specimens have been recovered from Morocco, including one featuring hindlimb, vertebral, and cranial bones that indicate Spinosaurus was extremely low-slung and short-legged, with its tall spines essentially confined to the dorsal vertebrae. It had a long neck, broad feet, dense limb bones, and was probably quite at home in the water. The fossils also show that Sigilmassasaurus is based on the base of a spinosaur neck; as Andrea Cau noted, the form of the Sigilmassasaurus vertebrae and the presence of the high vertebral spines may permitted the neck and head to have been held high by ligaments, giving it a pelican-like profile.
I have no opinion one way or the other on whether the Moroccan material is the same species as the original Egyptian material. Two species would not surprise me in the least. This is clouded by an effort to make the partial Moroccan skeleton a replacement type for the destroyed Egyptian material, with the possible strange outcome of Spinosaurus aegyptiacus, named for Egypt, being based on a specimen from Morocco, and the Egyptian material needing a new name (unfortunately, we couldn't go for turnabout and rename the Egyptian material maroccanus, because that's already in use).
Moroccan cranial specimens referred to Spinosaurus cf. S. aegyptiacus put a midline flare on the nasals and provide evidence for an individual potentially 16 to 18 meters long, the longest theropod known. A chunk of extremely elongated and narrow snout just shy of a meter long is responsible for this; the premaxillae are particularly drawn out, looking almost like a poorly-considered afterthought.
Sigilmassasaurus was one of the most obscure theropods you could ever hope to come across. For a while it was proposed to be a synonym of Carcharodontosaurus. It was described as having had a flexible neck with an inferred 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; these suggestions have not caught on. However, the idea of a long and strongly curved neck have merit, as noted above. Caudals referred to Sigilmassasaurus are possibly of Ouranosaurus (or an Ouranosaurus-like iguanodont) instead

Spinosauridae i.s.:

Taxon or Taxa: Time/Place: Comments:
Cristatusaurus lapparenti Taquet and Russell, 1998 (?Baryonyx or Suchomimus) Aptian (EK) of Niger Cristatusaurus had the bad fortune to run up against Suchomimus, which had much better press and type material. That said, Cristatusaurus would be the senior synonym if the two are the same animal, as the name is slightly older. It has mostly languished in obscurity.
"Sinopliosaurus" fusuiensis (N.D.) Hou, Yeh, and Zhao, 1975 EK of China This species is based on teeth thought at first to have come from a plesiosaur, but since reevaluated as belonging to a spinosaurid.
Suchosaurus: Owen, 1842 (?Baryonyx) S. cultridens (type) (Owen, 1841 [originally Crocodilus]) Barremian (EK) of England Based on distinctive teeth first thought to belong to a crocodilian (hence the name "crocodile reptile"), this animal may in fact be the same as Baryonyx (in which case the Baryonyx species would be transferred here).
S. girardi Sauvage, 1897-98 early Barremian (EK) of Portugal

Derived non-avetheropodan tetanurans and Avetheropoda:  Avetheropoda is a term first coined in Gregory S. Paul's classic 1988 book Predatory Dinosaurs of the World, and is similar in purpose today as to when it was first employed; namely, a combination of the allosaur group (in his classification including tyrannosaurids) and the members of what is today called Coelurosauria. The allosaur group is now called Carnosauria, but does not retain the traditional definition of including all large theropods. For example, the tyrannosaurids are now accepted as a group of coelurosaurians, closely related to the ornithomimosaurians. For a long time, large theropods were automatically carnosaurs and small theropods coelurosaurs, but it is interesting to note that the earliest version of this division foreshadowed the current thinking that the tyrannosaurs belong in Coelurosauria. Carnosauria and Coelurosauria have since been resurrected from this "waste bin" philosophy and reapplied to theropods in a manner that reflects more probable natural groupings than large versus small.

Avetheropoda i.s.:

Taxon or Taxa: Time/Place: Comments:
Gasosaurus constructus Dong and Tang, 1985 (?Kaijiangosaurus) Bathonian-Callovian (MJ) of China Rather unfortunately named from the standpoint of late 20th-early 21st century American culture (suggesting a theropod struggling with indigestion in an auditory fashion), Gasosaurus appears to be either the most basal known coelurosaurian or close the ancestry of both the coelurosaurians and carnosaurians. It is based on a partial skeleton.
Lourinhanosaurus antunesi Mateus, 1998 late Kimmeridgian-Tithonian (LJ) of Portugal This smallish (3.5-4 meters long) theropod, 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, but may be a basal coelurosaur instead. What this really means, of course, is that Lourinhanosaurus is probably something similar to a base-model tetanuran.

 

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