Tetanurae

    Tetanurae includes both birds and the more advanced classic theropods.  It has three major groups: Spinosauroidea, 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
      |--"Szechuanosaurus" zigongensis
      `--+--Xuanhanosaurus
           `--+--+--Condorraptor
                |     `--Piatnitzkysaurus
                `--+--Spinosauroidea
                     |    |--+--Dubreuillosaurus
                     |    |    `--Afrovenator
                     |    `--+--Megalosauridae
                     |         |    |--Torvosaurus
                     |         |    `--+--Megalosaurus
                     |         |         `--Poekilopleuron
                     |         `--+--+--Eustreptospondylus
                     |              |     `--Streptospondylus
                     |              `--Spinosauridae
                     |                   |--Baryonyx
                     |                   `--+--Irritator
                     |                        `--Spinosaurus
                     `--+--Monolophosaurus
                          `--Avetheropoda
                               |-->Carnosauria
                               `-->Coelurosauria           

Tetanurae:

Taxon or Taxa: Time\Place: Comments:
"Szechuanosaurus" zizongensis Gao, 1993 Bathonian-Callovian (MJ) of China "S." zigongensis is based on a partial headless skeleton, which was referred to a genus based on teeth (figure out that one!).  Theropod teeth being what they are, Szechuanosaurus proper is not all that useful, but this skeleton and assorted referred postcranial material are.
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, and has led others to suggest megalosaurid affiliations.  It had four fingers and possibly a clavicle, which is rarely preserved in dinosaurs.
Condorraptor currumili Rauhut, 2005 Callovian (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 Callovian (MJ) of Argentina This animal is burdened with 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!).

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:
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).
"Brontoraptor" (N.N.) Redman, 1995 (?Torvosaurus) Kimmeridgian (LJ) of Colorado This megalosaurid may be the same as Torvosaurus, although some consider it to be more derived. 
"Calamospondylus" foxi (N.D.) Lydekker, 1889 (Calamosaurus) Barremian (EK) of England Also known as Calamosaurus, this is a small theropod that can be assigned no higher than Tetanurae, but may be a basal coelurosaurian.  It is based on two cervical vertebrae and an unusual referred tibia.
Chilantaisaurus tashuikouensis Hu, 1964 Aptian-Albian (EK) of China This animal is poorly known, but apparently had whopping big claws and hands.
Iliosuchus incognitus Huene, 1932 mid Bathonian (MJ) of England Iliosuchus is based upon two very small ilia (upper hip bone) that have an unusual vertical ridge on the outside surface.  This is similar to the condition in tyrannosaurids and Piatnizkysaurus.
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.
?Kelmayisaurus petrolicus (?N.D.) Dong, 1973 ?Valanginian-Albian (EK) of China This theropod is based on parts of the upper and lower jaws, which have been described as being like those of Ceratosaurus.  A possible second, undescribed species is apparently very long, but may not actually exist.
Magnosaurus nethercombensis Huene, 1932 (originally Megalosaurus nethercombensis, Huene 1926) Aalenian-Bajocian (MJ) of England This fragmentary theropod may eventually turn out to be a species of Megalosaurus, as originally named.  Otherwise, it's notable as one of the few dinosaurs yet known from the Aalenian.
"Megalosaurus" hesperis Waldman, 1974 Aalenian-Bajocian (MJ) of England This species is based on a partial skull that is similar to that of Megalosaurus.
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 doesn't appear to fall neatly into any more derived theropod groups, and may represent a hitherto-unknown lineage of basal tetanurans, or a carcharodontosaurid.  
"Merosaurus newmani" (N.N.) Welles, Powell, and Pickering vide Pickering, 1995 late Sinemurian (EJ) of England "Merosaurus" is based on leg material that was once part of the type material of Scelidosaurus.  It seems to be a basal tetanuran.
Metriacanthosaurus parkeri Walker, 1964 (originally Megalosaurus parkeri Huene, 1926) early-mid Oxfordian (LJ) of England This theropod is odd in that it bears a resemblance to sinraptorids in some of its material (specifically, its vertebrae resemble that of Yangchuanosaurus), but is from Europe.  It has a slight fin-back, and was for a time considered a spinosaurid.
Piveteausaurus divesensis Taquet and Welles, 1977 (originally Eustreptospondylus divesensis Walker, 1964) late Callovian (MJ) of France This species is based on a braincase that may pertain to an animal similar to Proceratosaurus or Piatnitzkysaurus.  Otherwise, it is rather obscure.
"Streptospondylus" cuvieri (N.D.) Owen, 1842 early Bathonian (MJ) of England This dubious species of Streptospondylus is based on a partial dorsal vertebra, and let no one else tell you otherwise!
Valdoraptor oweni Olshevsky, 1991 (originally Megalosaurus oweni Lydekker, 1889) Berriasian-Valanginian (EK) of England  Valdoraptor is based on some odd metatarsi from a moderately-sized theropod.

Basal Spinosauroidea and 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.  In general, basal spinosauroids and megalosaurids are known for their long, low builds and short, stout arms. 
    Megalosaurus is currently in the midst of a massive taxonomic overhaul, and it is very likely that once this is published we will see the introduction of many new taxa.  This family is also known as Torvosauridae; of course, if it is proved 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:
Afrovenator abakensis Sereno, Wilson, Larsson, Dutheil, and Sues, 1994 Hauterivian (EK) 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 eustreptospondyline 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.
Eustreptospondylus oxoniensis Walker, 1964 (?Magnosaurus) 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.
Megalosaurus bucklandii Buckland, 1824 (species after Ritgen, 1826) Bathonian-?early Oxfordian (MJ-?LJ) of England, ?France, and ?Portugal The prototypical "big theropod" and the first classic dinosaur to be named (almost; what is now known to be a sauropod tooth named Rutellum implicatum in 1699 beats out Scrotum humanum Brookes, 1763, based on a femur end that probably pertained to a Megalosaurus; usually we only count Megalosaurus Buckland, 1824 because his guess was closer to what it really was), Megalosaurus is in the midst of an overhaul.  Its type specimen is a dentary, which limits comparison to other taxa, although all the material found from its type locality that is theropod may belong to the type.  Many elements have been referred to it.
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, the rest of it was blown up in WWII, so casts are used to study it.
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.  
Torvosaurus tanneri Galton and Jensen 1979 (including Edmarka rex Bakker, Kralis, Siegwarth, and Filla, 1992) Kimmeridgian (LJ) of Colorado and Wyoming; ?late Kimmeridgian-early Tithonian (LJ) of Portugal 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.

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.   
    With only one "baryonychid," I got rid of Baryonychidae.  Baryonyx's species are known from better material than the spinosaurids, and have less cranial ornamentation.  It may be the same as a creature, Suchosaurus, named in the 19th century!

Taxon or Taxa: Time\Place: Comments:
Baryonyx:
 Charig and Milner, 1986 (?Suchosaurus)		 B. walkeri (type) Charig and Milner, 1986 Barremian (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 spinosaurian may have also lived in the Aptian of Niger.  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.
Irritator challengeri Martill, Cruickshank, Frey, Small, and Clarke, 1996 (including Angaturama limai Kellner and Campos, 1996) (?Spinosaurus) 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.  Irritator itself could be the same as Spinosaurus.
Spinosaurus: Stromer, 1915  (?Irritator) S. aegyptiacus (type) Stromer, 1915 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.  S. marrocanus may or may not be a valid species; some workers consider it to be the same thing as the type species.  Material dubbed "Spinosaurus B" appears to belong to two theropods: the vertebrae to Sigilmassasaurus, and the limb material to Carcharodontosaurus.
New 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.  
?S. marrocanus Russell, 1996 ?Albian (EK) of Morocco

Spinosauridae i.s.:

Taxon or Taxa: Time/Place: Comments
Suchosaurus: Owen, 1841 (?Baryonyx) S. cultridens (type) Owen, 1841 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.
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. 

Taxon or Taxa: Time\Place: Comments:
Monolophosaurus jiangi Zhao and Currie, 1995 Oxfordian (LJ) 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.

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.

 

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