Theropoda Marsh, 1881
Official Definition- (Allosaurus fragilis <- Plateosaurus engelhardti, Heterodontosaurus tucki) (Naish, Cau, Holtz, Fabbri and Gauthier, 2020; originally from Naish, Cau, Holtz, Fabbri and Gauthier, in press vide Dal Sasso, Maganuco and Cau, 2018; Registration Number 216)
Other definitions- (Passer domesticus <- Saltasaurus loricatus) (Sereno, 2004; modified from Sereno, 1998; modified from Gauthier, 1986)
(Passer domesticus <- Cetiosaurus oxoniensis) (Holtz and Osmolska, 2004; modified from Gauthier, 1986)
(Allosaurus fragilis <- Morosaurus impar) (modified from Kischlat, 2000)
(Allosaurus fragilis <- Plateosaurus engelhardti) (modified from Clarke et al., 2004)
(Passer domesticus <- Diplodocus carnegii, Triceratops horridus) (Baron, Norman and Barrett, 2017)
= Goniopoda Cope, 1866
= Therophagi Jaekel, 1914
= Carnosauriformes Cooper, 1985
= Theropoda sensu Sereno, 1998
Definition- (Passer domesticus <- Saltasaurus loricatus) (modified)
= Theropoda sensu Kischlat, 2000
Definition- (Allosaurus fragilis <- Morosaurus impar) (modified)
= Theropoda sensu Clarke, Gauthier, de Queiroz, Joyce, Parham and Rowe, 2004
Definition- (Allosaurus fragilis <- Plateosaurus engelhardti)
= Theropoda sensu Holtz and Osmolska, 2004
Definition- (Passer domesticus <- Cetiosaurus oxoniensis) (modified)
= Theropoda sensu Baron, Norman and Barrett, 2017
Definition- (Passer domesticus <- Diplodocus carnegii, Triceratops horridus)
Other diagnoses- Marsh's (1881) original diagnosis consisted largely of plesiomorphies- carnivorous; limb bones hollow; digits with prehensile claws; digitigrade pes. The distal pubes are only fused in adult neotheropods. "Vertebrae more or less cavernous" refers to the extremely constricted dorsal centra of Allosaurus, which aren't present in most theropods. "Post-pubis present" probably refers to Allosaurus' elongate pubic boot, which is only present in some avetheropods.
Marsh (1884) added more plesiomorphies- premaxilla toothed; external nares placed anteriorly; large antorbital fossa; forelimbs short; propubic pelvis.
Comments- Marsh (1881) named Theropoda as a dinosaur suborder containing only the Allosauridae, in which he placed Allosaurus, Creosaurus and Labrosaurus (both of the latter now recognized as synonyms of Allosaurus). By 1884, Marsh had raised Theropoda to an order and expanded it to include all carnivorous dinosaurs, as well as what are today recognized as basal sauropodomorphs (often mixed with cranial elements of canivorous crurotarsans). This was the standard for many decades, as seen in Romer's (1956) classic work, in which theropods consist of coelurosaurs, carnosaurs and prosauropods. The monophyly of theropods was questioned by Huene (1914), who placed most of the larger taxa such as Allosaurus and Megalosaurus in Sauropodomorpha (his Pachypodosauria) while the smaller taxa (which he named Coelurosauria) had branched off earlier. In the 1960's, workers began to recognize the monophyly of coelurosaurs and carnosaurs to the exclusion of basal sauropodomorphs (e.g. Colbert, 1964). Paul (1984) was the first author to use a theropod phylogeny similar to todays, with deinonychosaurs (albeit paraphyletic), tyrannosaurids, allosaurids, Eustreptospondylus, Ceratosaurus and coelophysoids forming successively more distant sister taxa to birds. Gauthier's (1984) thesis also had a modern topology, with deinonychosaurs, ornithomimids, carnosaurs and ceratosaurs (the latter two improbably inclusive, containing tyrannosaurids and coelophysoids respectively) successively further from birds, and is the basis of our current nomenclature for major clades.
Goniopoda, Harpagosauria, Therophagi and Carnosauriformes- Cope (1866) named Goniopoda for Dryptosaurus (his Laelaps) and Streptospondylus (his Megalosaurus) based on his misinterpretation of their astragalus as a fibula, as a fibula which wraps distally around the tibia would be unique. The taxon was almost exclusively used by Cope through the 1880's for carnivorous dinosaurs even after the astragalus was correctly identified. He eventually gave it a scope and diagnosis similar to Marsh's Theropoda (e.g. Cope, 1883). After Cope's death, Theropoda became the term almost exclusively used for carnivorous dinosaurs.
Harpagosauria was seen as a paraphyletic order of dinosaurs by Haeckel (1866), containing Megalosaurus, Plateosaurus and Pelorosaurus (but not Iguanodon). Haeckel refers to these as the carnivorous dinosaurs, which led Cope to synonymize the taxon with his Goniopoda (starting in 1870, and consistantly misspelled Harpagmosauria). However, Haeckel's original usage suggests it is instead the equivalent to Saurischia. Baur (1887) uses Harpagosauria as a dinosaurian group containing only Goniopoda, with Sauropoda separate. Haeckel (1895) later used Harpagosauria as a junior synonym for his new dinosaurian taxon Dysdracones including both Arctopoda (containing basal sauropodomorphs) and Theropoda, with sauropods now placed in his Eudracones that contained all herbivorous dinosaurs. Harpagosauria was said to contain the carnivorous dinosaurs with sharp teeth and claws. It has not been used since.
Therophagi was named by Jaekel (1914) for a saurischian group containing the taxa then usually referred to Theropoda- anchisaurids, zanclodontids (mixing sauropodomorph postcrania with crurotarsan crania), ceratosaurids, megalosaurids and tyrannosaurids. Plateosauridae and Sauropoda were placed in the Allophagi however. The names have not been used since.
Proposed as part of a cladistic reclassification of ornithischians, Carnosauriformes was named by Cooper (1985) as a cohort of dinosaurs "retaining the primitive condition of recurved thecodontian dentition with finely serrated cutting edges." No justification for using this name over Theropoda was given, and it is today rightfully considered a junior synonym.
Theropoda defined- Gauthier (1986) was the first to phylogenetically define Theropoda, as "birds and all saurischians that are closer to birds than they are to sauropodomorphs." Variations on this definition have been most common, with Sereno (1998) using Neornithes and Saltasaurus, specified by Sereno (2004) as Passer domesticus and Saltasaurus loricatus. Holtz and Osmolska (2004) chose Cetiosaurus oxoniensis as the sauropodomorph specifier instead. However, this class of definition violates Phylocode Recommendation 11A- "Definitions of converted clade names should be stated in a way that attempts to capture the spirit of traditional use to the degree that it is consistent with the contemporary concept of monophyly." While birds are currently thought to be theropods, this was not the consensus until over a century after Theropoda was named. Similarly, Clarke et al.'s (2004) definition using Plateosaurus engelhardti as an external specifier is problematic since basal sauropodomorphs were often included in Theropoda until the 1960s. Kischlat (2000) suggested all taxa closer to Allosaurus than to Morosaurus, which is valid in using taxa Marsh (1881) and everyone since have recognized as being theropod and non-theropod.  The official definition by Naish et al. (2020) retained Allosaurus but also used Plateosaurus and the basal ornithischian Heterodontosaurus.
Ex-theropods- Numerous taxa (at least 130) have been incorrectly placed in Theropoda in the past, including ornithosuchids, poposaurids, most basal avemetatarsalians and basal sauropodomorphs, and many Triassic archosauriforms known only from teeth. This site has an entire section devoted to ex-theropods, so they are not discussed further here.
References- Cope, 1866. [On the anomalous relations existing between the tibia and fibula in certain of the Dinosauria]. Proceedings of the Academy of Natural Sciences of Philadelphia. 18, 316-317.
Haeckel, 1866. Generelle Morphologie der Organismen. Allgemeine Grundzuge der organischen Formen Wissenschaft, mechanisch begrundet durch die von Charles Darwin reformiete Deszendenz-Theorie. II. Allgemeine Entwicklungsgeschichte der Organismen. Kritische Grundzuge der mechanischen Wissenschaft von dan entstehenden Formen der Organismen, begrundet durch die Deszendenz-Theorie. Georg Reimer. 462 pp.
Cope, 1870. Synopsis of the extinct Batrachia and Reptilia of North America. Transactions of the American Philosophical Society. 14, 1-252.
Marsh, 1881. Principal characters of American Jurassic dinosaurs. Part V. American Journal of Science. 21, 417-423.
Cope, 1883. On the characters of the skull in the Hadrosauridae. Proceedings of the Philadelphia Academy of Natural Sciences. 35, 97-107.
Marsh, 1884. Principal characters of American Jurassic dinosaurs. Part VIII. The order Theropoda. American Journal of Science. 27, 329-340.
Baur, 1887. On the phylogenetic arrangement of the Sauropsida. Journal of Morphology. 1, 93-104.
Haeckel, 1895. Systematische Phylogenie: Entwurf eines Nat�rlichen Systems der Organismen auf Grund ihrer Stammesgeschichte. Dritter Theil: Systematische Phylogenie der Wirbelthiere (Vertebrata). Georg Reimer, Berlin. 660 pp.
Huene, 1914. Das nat�rliche System der Saurischia [The systematics of the Saurischia]. Centralblatt f�r Mineralogie, Geologie und Pal�ontologie. 1914, 154-158.
Jaekel, 1914. �ber die Wirbeltierfunde in der oberen Trias von Halberstadt. Palaontologische Zeitschrift. 1(1), 155-215.
Romer, 1956. Osteology of the Reptiles. University of Chicago Press. 772 pp.
Colbert, 1964. Relationships of the saurischian dinosaurs. American Museum Novitates. 2181, 1-24.
Gauthier, 1984. A cladistic analysis of the higher systematic categories of the Diapsida. PhD thesis. University of California. 564 pp.
Paul, 1984. The archosaurs: A phylogenetic study. Third Symposium on Mesozoic Terrestrial Ecosystems, Short Papers. 175-180.
Cooper, 1985. A revision of the ornithischian dinosaur Kangnasaurus coetzeei Haughton, with a classification of the Ornithischia. Annals of the South African Museum. 95(8), 281-317.
Gauthier, 1986. Saurischian monophyly and the origin of birds. Memoirs of the Californian Academy of Sciences. 8, 1-55.
Sereno, 1998. A rationale for phylogenetic definitions, with application to the higher-level taxonomy of Dinosauria. Neues Jahrbuch f�r Geologie und Pal�ontologie Abhandlungen. 210, 41-83.
Kischlat, 2000. Tecodoncios: A aurora dos Arcosaurios no Triassico. in Holz and De Rose (eds.). Paleontologia do Rio Grande do Sul. 273-316.
Clarke, Gauthier, de Queiroz, Joyce, Parham and Rowe, 2004. A phylogenetic nomenclature for the major clades of Amniota Haeckel 1866, with emphasis on Aves Linnaeus 1758. First International Phylogenetic Nomenclature Meeting, Abstracts. 30.
Holtz and Osm�lska, 2004. Saurischia. In Weishampel, Dodson and Osm�lska (eds.). The Dinosauria. 2nd ed. University of California Press. 21-24.
Sereno, 2004. Phylogenetic nomenclature for stem crocodilians and birds, exclusive of Pterosauria. First International Phylogenetic Nomenclature Meeting, Abstracts. 26.
Baron, Norman and Barrett, 2017. A new hypothesis of dinosaur relationships and early dinosaur evolution. Nature. 543(7646), 501-506.
Dal Sasso, Maganuco and Cau, 2018. The oldest ceratosaurian (Dinosauria: Theropoda), from the Lower Jurassic of Italy, sheds light on the evolution of the three-fingered hand of birds. PeerJ. 6:e5976.
Naish, Cau, Holtz, Fabbri and Gauthier, 2020. Theropoda O. C. Marsh 1881 [D. Naish, A. Cau, T. R. Holtz, Jr., M. Fabbri, and J. A. Gauthier], converted clade name. In de Queiroz, Cantiono and Gauthier (eds.). Phylonyms: A Companion to the PhyloCode. Taylor & Francis Group. 1234-1245.

undescribed theropod (Fitch, Lovelace and Stocker, 2020)
Early-Mid Carnian, Late Triassic
Popo Agie Formation, Chugwater Group, Wyoming, US
Material- (UWGM 1975) anterior dorsal vertebra, incomplete posterior dorsal vertebra (~21 mm), two incomplete sacral vertebrae, metacarpal I (~9 mm), two partial manual unguals, proximal ischium, proximal femur, tibial fragment, proximal fibula, astragalus (~21 mm trans), distal metatarsal I, proximal metatarsal III
Comments- Discovered in 2013.  Adding this to Nesbitt's Tawa matrix resulted Fitch et al. recovering the taxon as the sister taxon of Neotheropoda, more derived than Eodromaeus, Chindesaurus or Tawa.  This relationship was based on elongated posterior dorsal centra shared with Eodromaeus and neotheropods, and an astragalus much wider than anteroposteriorly deep, very reduced surface for the ventromedial calcanear process on the astragalus (absent in neotheropods), and a transversely expanded posterior metatarsal III in proximal view shared with neotheropods.  It was excluded from Neotheropoda based on the lack of astragalocalcanear fusion (contra the abstract), an anterolateral astragalar process and the proximal elliptical astragalar fossa..
Reference- Fitch, Lovelace and Stocker, 2020. The oldest dinosaur from the northern hemisphere and the origins of Theropoda. The Society of Vertebrate Paleontology 80th Annual Meeting, Conference Program. 140-141.

unnamed theropod (Pinheiro, 2016)
Early Norian, Late Triassic
Botucarai Hill, Caturrita Formation, Brazil

Material- (MMACR 039 T) distal femur (21 mm wide)
Comments- Discovered in 2015, Pinheiro (2016) described this and referred it to Neotheropoda.  However, Ezcurra (2017) noted it lacks a mediodistal crest unlike neotheropods, so may belong to a more basal theropod.
Reference- Pinheiro, 2016. A fragmentary dinosaur femur and the presence of Neotheropoda in the Upper Triassic of Brazil. Revista Brasileira de Paleontologia. 19, 211-216.
Ezcurra, 2017. A new early coelophysoid neotheropod from the Late Triassic of northwestern Argentina. Ameghiniana. 54, 506-538.

Chilesaurus Novas, Salgado, Suarez, Agnolin, Ezcurra, Chimento, Cruz, Isasi, Vargas and Rubilar-Rogers, 2015
C. diegosuarezi Novas, Salgado, Suarez, Agnolin, Ezcurra, Chimento, Cruz, Isasi, Vargas and Rubilar-Rogers, 2015
Tithonian, Late Jurassic
Toqui Formation, Chile
Holotype
- (SNGM-1935) (~1.6 m; juvenile) partial skull, incomplete dentary, most cervical vertebrae including fourth, over eleven incomplete to complete dorsal vertebrae, dorsal rib fragments, second sacral vertebra (24.77 mm), third sacral vertebra (26.15 mm), fourth sacral vertebra (23.04 mm), fifth sacral vertebra (21.60 mm), sixth sacral vertebra (19.88 mm), first caudal vertebra (18.78 mm), second caudal vertebra (18.25 mm), third caudal vertebra (20.40 mm), fourth caudal vertebra, fifth caudal vertebra (21.97 mm), sixth caudal vertebra (19.62 mm), seventh caudal vertebra (20.11 mm), eighth caudal vertebra (21.30 mm), ninth caudal vertebra (19.72 mm), tenth caudal vertebra (19.88 mm), eleventh caudal vertebra, at least two proximal chevrons, scapulae (114.87, 116.33 mm), coracoids, humeri (97.84, 94.05 mm), radii (69.82, 68.29 mm), ulnae (~75.93 mm), distal carpal I, metacarpals I (27.15, 26.68 mm), phalanx I-1 (28.59 mm), metacarpals II (39.77, 39.23 mm), phalanges II-1 (16.48, 15.97 mm), phalanx II-2 (13.61 mm), metacarpals III, partial ilia, pubis (95.67 mm), ischium (101.17 mm), femora (142.45, 140.75 mm), incomplete tibiae, fibula
Paratypes- (SNGM-1936) (~1.3 m; juvenile) three incomplete anterior dorsal vertebrae, partial dorsal rib, distal humerus, distal radius, incomplete ulna, metacarpals I (24.81, 24.08 mm), phalanges I-1 (25.77 mm), metacarpal II (36.14 mm), phalanx II-1, phalanx II-2 (14.67 mm), partial metacarpal III, incomplete ilia (100.62 mm), pubes (97.73 mm), ischia (101.62 mm), femur (114.59 mm), tibiae (128.22 mm), astragalus (27.36 mm trans), metatarsal II (61.96 mm), phalanx II-1 (23.40 mm), phalanx II-2 (20.92 mm), metatarsal III (64.82 mm), metatarsal IV (55.49 mm)
(SNGM-1937) (~1.3 m; juvenile) forelimbs including coracoids, humeri (one partial; 87 mm), radius (64 mm), ulna, metacarpal I (21.66 mm), phalanx I-1 (22.92 mm), manual ungual I (27.83 mm), metacarpal II (31.52 mm), phalanx II-1 (18 mm), proximal phalanx II-2, manual ungual II (29 mm), metacarpal III (21.7 mm), tibiae (one partial; 114.61 mm), fibulae (one partial; ~144 mm), incomplete metatarsal I, phalanx I-1 (33.60 mm), pedal ungual I (24.93 mm), incomplete metatarsal II, phalanx II-1 (25.11 mm), phalanx II-2 (21.71 mm), pedal ungual II (31.81 mm), metatarsal III (71.15 mm), phalanx III-1 (25.92 mm), phalanx III-2 (19.00 mm), phalanx III-3 (19.10 mm), pedal ungual III (~24.73 mm), metatarsal IV, phalanx IV-1 (19.37 mm), phalanx IV-2 (17.47 mm), phalanx IV-3 (16.89 mm), phalanx IV-4 (15.52 mm)
(SNGM-1938) seven incomplete to fragmentary dorsal vertebrae, several dorsal ribs, scapulae (160.05 mm), coracoids, humeri (130.86 mm), radii, ulnae, both incomplete manus including manual ungual I (35.69 mm), metacarpals III (42.95, 40.11 mm)
Referred- (SNGM-307) pelvis (Chimento, 2015)
(SNGM-1887) distal carpal I, metacarpal I (49.95 mm), proximal phalanx I-1, incomplete metacarpal II (75.65 mm), phalanx II-2, metacarpal III (62.71 mm), phalanx III-2?, phalanx III-3? (Salgado et al., 2008)
(SNGM-1888) distal tibia, distal fibula, astragalus (61.50 mm trans), calcaneum, distal tarsal IV, metatarsal II (121.95 mm), phalanx II-1 (45.77 mm), phalanx II-2 (41.93 mm), metatarsal III (133.35 mm), proximal phalanx III-1, metatarsal IV (118.19 mm), proximal phalanx IV-1, incomplete pedal ungual (Salgado et al., 2008)
(SNGM-1889) incomplete ilium (Salgado et al., 2008)
(SNGM-1890) metatarsal II (82.75 mm), metatarsal III (89.66 mm), partial metatarsal IV (Chimento, 2020)
(SNGM-1894) anterior dorsal centrum (Salgado et al., 2008)
(SNGM-1895) proximal tibia (Salgado et al., 2008)
(SNGM-1898) anterior dorsal centrum (Salgado et al., 2008)
(SNGM-1900) posterior dorsal centrum (Salgado et al., 2008)
(SNGM-1901) distal tibia (Salgado et al., 2008)
(SNGM-1903) anterior dorsal centrum (Salgado et al., 2008)
(SNGM-8193) pelvis (Chimento, 2015)
Diagnosis- (after Novas et al., 2015; note only convergences with closely related taxa or alvarezsaurids are mentioned here) dentary deeper anteriorly than posteriorly; teeth basally constricted (also in maniraptoriforms); teeth serrated only apically; tooth crowns with large apical wear facets; posterior cervical pleurocoels (also in basal neotheropods); cervicals with septate pleurocoels; coracoid with transversely thick margins; manual phalanx II-2 shorter than II-1 (also in coelophysoids and some alvarezsaurids); manual digit III atrophied (also in some alvarezsaurids); supratrochanteric process; ischiadic peduncle of ilium robust (also in some alvarezsaurids); supracetabular crest absent; pubis fully retroverted (also in derived alvarezsaurids); small pubic boot (also in coelophysoids and derived alvarezsaurids); ischia connected through extended medial lamina; femoral greater trochanter anteroposteriorly expanded (also in alvarezsaurids); pedal digit I robust; metatarsal II transversely wider than the other metatarsals (also in Tawa).
Other diagnoses- Contra Novas et al. (2015), the premaxilla is not particularly short or deep. Fine serrations are plesiomorphic for archosaurs. The coracoid is subquadrangular in megalosaurids, Ceratosaurus, coelophysoids and many basal taxa. The pubis is not more rod-like than most neotheropods, nor is the pubic apron narrower. Metatarsal I is proximally compressed transversely in all theropods.
If I'm correct that Chilesaurus is a non-neotheropod sister to Daemonosaurus, the following suggested characters by Novas et al. also don't apply- the plate-like subnarial premaxillary process is shared with Daemonosaurus. The absent mediodistal femoral crest is true in non-averostrans (and most alvarezsaurids). The distally 'triangular' calcaneum is also primitive, being seen in e.g. Eoraptor and Guaibasaurus. The lack of a fibular crest, astragalar ascending process lower than its body, and robust and elongate metatarsal I are also true of most non-neotheropods.
Comments- Novas et al. (2015) state there are four paratypes, but while the other SNGM-193x series are obvious possibilities, it's unknown if this assumption is correct and if so, what the other paratype is (SNGM-1887 and 1888 are most complete, so most likely). A manual phalanx III-1 is also reported, but which specimen preserves it is unknown. Salgado et al. (2008) report "articulated phalanges ... III-2, and III-3 are preserved" in SNGM-1887, but Novas et al. say metacarpal III's "digit comprises a single minute phalanx." There are several elements illustrated in the skeletal or coded for (e.g. cervical ribs, metatarsal V), whose existence must be confirmed by future publications.
Salgado et al. (2008) first reported Chilesaurus elements as non-tetanurine Theropoda indet. (SNGM-1888, 1889, 1895, 1901) and Tetanurae indet. (SNGM-1887, 1894, 1898, 1900, 1903), due to the plesiomorphic tarsus and metatarsus yet more derived-looking manus and keeled anterior dorsals. Once more complete specimens were found, Novas et al. (2015) described them as a new taxon of non-orionidan tetanurine. This was based on four datasets, but Chilesaurus is mis- or uncoded for 12-14% of characters in at least three of them (Mortimer, online 2015). Once the datasets were corrected and improved, and Chilesaurus was also analyzed in an unpublished coelurosaur matrix and Butler's ornithischian matrix, the genus most parsimoniously groups with maniraptoriforms and more precisely alvarezsaurids. It emerged strongly supported in that position in my unpublished matrix and Nesbitt et al.'s dinosauromorph matrix once only verified codings of Chilesaurus were used, took only 4 steps to move there without any theropod characters in Butler's matrix, and is one of the most parsimonious possibilities in Carrano et al.'s basal tetanurine matrix if only its verifiable codings are used. A basal tetanurine position is strongly rejected if alvarezsaurids are included (13 more steps in my matrix; 10 more in Butler's matrix). Yet both of these placements seem unlikely due to the incongruities caused by inserting Chilesaurus there, so that even though it's not most parsimonious, convergence between Chilesaurus and tetanurines seems more likely than reversals in Chilesaurus. The fact verifiable Chilesaurus emerges outside Neotheropoda in one of the most parsimonious trees when Velociraptor is excluded from Nesbitt et al.'s matrix and only takes 1 more step to place there in Carrano et al.'s matrix would then make sense. This would allow many characters to be plesiomorphic (e.g. no fibular crest, short astragalar ascending process, large pedal digit I), and also agrees with its placement close to Neotheropoda in Otero and Pol's sauropodomorph-focused trees. In Nesbitt-based trees, when outside Neotheropoda, Chilesaurus emerged sister to Daemonosaurus with which it shares- short snout; broad subnarial premaxillary process; three premaxillary teeth (also in Tawa); decurved dentary; procumbant anterior teeth. However, verifiable Chilesaurus falls out in Sauropodomorpha with 2-7 more steps, and in Ornithischia with 4-8 more. So it could belong to those clades instead, but more definite statements will require an osteology of the taxon to clear up the coding incongruities and briefness of its original description.
References- Salgado, Cruz, Suarez, Fernandez, Gasparini, Palma-Heldt and Fanning, 2008. First Late Jurassic dinosaur bones from Chile. Journal of Vertebrate Paleontology. 28(2), 529-534.
Mortimer, online 2015. http://theropoddatabase.blogspot.com/2015/06/chilesaurus-brings-out-bandit-in-me.html
Chimento, 2015. Anatomia pelvica de un nuevo dinosaurio tetanuro (Dinosauria, Theropoda) del Jurasico tardio de Chile. XXIX Jornadas Argentinas de Paleontolog�a de Vertebrados, resumenes. Ameghiniana. 52(4) suplemento, 12.
Novas, Salgado, Suarez, Agnolin, Ezcurra, Chimento, Cruz, Isasi, Vargas and Rubilar-Rogers, 2015. An enigmatic plant-eating theropod from the Late Jurassic period of Chile. Nature. 522, 331-334.
Soto-Acuna, Otero, Rubilar-Rogers and Vargas, 2015. Arcosaurios no avianos de Chile. Publicacion Ocasional del Museo Nacional de Historia Natural, Chile. 63, 209-263.
Chimento, Agnolin, Novas, Ezcurra, Salgado, Isasi, Suarez, de la Cruz, Rubilar-Rogers and Vargas, 2017. Forelimb posture in Chilesaurus diegosuarezi (Dinosauria, Theropoda) and its behavioral and phylogenetic implications. Ameghiniana. 54(5), 567-575.

Erythrovenator M�ller, 2021
= "Erythrovenator" M�ller, 2020 online
E. jacuiensis M�ller, 2021
= "Erythrovenator jacuiensis" M�ller, 2020 online
Middle Carnian-Early Norian, Late Triassic
Niemeyer Site, Santa Maria or Caturrita Formation, Candelaria Sequence, Brazil
Material- (CAPPA/UFSM 0157) proximal femur (~190 mm)
Diagnosis- (after M�ller, 2021) absence of a raised dorsolateral trochanter of the femur; absence of a folded anteromedial tuber.
Comments- This was discovered between 2014 and 2016 and initially described as cf. Dinosauromorpha by Pavanatto et al. (2018).  M�ller (2021) named it and redescribed it as a new taxon of theropod.  Using M�ller and Garcia's pan-avian analysis, it emerged as a theropod based on the anterior trochanter being separated from the shaft by a celft, but was outside Neotheropoda.  Unfortunately, M�ller's original 2020 preprint has no mention of ZooBank.  Thus according to ICZN Article 8.5.3 (an electronic work must "be registered in the Official Register of Zoological Nomenclature (ZooBank) (see Article 78.2.4) and contain evidence in the work itself that such registration has occurred"), "Erythrovenator jacuiensis" M�ller, 2020 is a nomen nudum that was valid once published in April 2021.
References- Pavanatto, Pretto, Kerber, M�ller, Da-Rosa and Dias-da-Silva, 2018. A new Upper Triassic cynodont-bearing fossiliferous site from southern Brazil, with taphonomic remarks and description of a new traversodontid taxon. Journal of South American Earth Sciences. 88, 179-196.
M�ller, 2021 (online 2020). A new theropod dinosaur from a peculiar Late Triassic assemblage of southern Brazil. Journal of South American Earth Sciences. 107, 103026.

Nhandumirim Marsola, Bittencourt, Butler, Da Rosa, Say�o and Langer, 2019
= "Nhandumirim" Marsola, 2018
N. waldsangae Marsola, Bittencourt, Butler, Da Rosa, Say�o and Langer, 2019
= "Nhandumirim waldsangae" Marsola, 2018
Middle Carnian, Late Triassic
Cerro da Alemoa, Alemoa Member of Santa Maria Formation, Brazil

Holotype- (LPRP/USP 0651) (three year old juvenile) incomplete posterior dorsal vertebra, two posterior dorsal centra, second sacral centrum (15 mm), sacral centrum (14 mm), two sacral ribs, three incomplete proximal caudal vertebrae, two incomplete mid caudal vertebrae, two distal caudal vertebrae (one partial), chevron, incomplete ilium, femur (120 mm), partial tibia, fibula, metatarsal II, metatarsal IV, five pedal phalanges (one incomplete), three proximal pedal unguals, fragments
Diagnosis- sharp longitudinal keels on ventral surface of proximal caudal centra; brevis fossa projecting for less than three-quarters of the length of ventral surface of postacetabular process; proximally short dorsolateral trochanter that terminates well distal to level of femoral head; distal tibia with mediolaterally extending tuberosity on anterior surface, in addition to a tabular posterolateral flange; conspicuous, anteromedially oriented semicircular articular facet on distal fibula; straight metatarsal IV.
Comments- Discovered by April 2015, Marsola et al. (2015) first announced LPRP/USP 0651 as "a new small-sized gracile dinosaur" recovered "as a basal saurischian dinosaur, with no clear relationship to less inclusive groups. Yet interestingly, its variable position in the different recovered phylogenetic hypotheses accompanied that of Eoraptor lunensis, suggesting a possible affinity to that taxon."  Marsola's (2018) thesis includes a chapter which is a pre-submission version of the eventual description written October 2017, making that use of Nhandumirim waldsangae a nomen nudum (ICZN Article 8.1.1).  Marsola et al. (2019) officially named and described the taxon, finding it sister to neotheropods in Cabreira et al.'s dinosauromorph analysis and in a saurischian polytomy with Tawa+Neotheropoda and sauropodomorphs in Nesbitt's archosaur matrix.
References- Marsola, Bittencourt, Da-Rosa and Langer, 2015. A small-sized saurischian dinosaur from the Late Triassic Santa Maria Formation, southern Brazil. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 175.
Marsola, 2018. Triassic dinosauromorphs from southern Brazil and biogeographic patterns for the origin of dinosaurs. PhD thesis, Universidad de Sao Paulo. 199 pp.
Marsola, Bittencourt, Butler, Da Rosa, Say�o and Langer, 2019. A new dinosaur with theropod affinities from the Late Triassic Santa Maria Formation, south Brazil. Journal of Vertebrate Paleontology. e1531878.