Saturday, October 5, 2024

New website for The Theropod Database plus new nomina nuda

I had to move hosts, so the new website for The Theropod Database is
https://theropoddatabase.github.io/ .  We're working out some encoding issues for special characters, but in the meantime here are some nomina nuda that have not been reported before.

I'm sure Dalman's new tyrannosaur names have been making the rounds based on his new curriculum vitae at https://www.montana.edu/earthsciences/graduate-program/students/cv/Sebastian_Dalman.html .  Here's some informed guesswork as to what they are...

"Bistityrannus" Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review in Dalman, online 2024
?= "Alamotyrannus" Dalman and Lucas, in press in Dalman, 2013 in part
"B. anax" Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review in Dalman, online 2024
?= "Alamotyrannus brinkmani" Dalman and Lucas, in press in Dalman, 2013 in part
Etymologies- Bisti is Navajo for "large area of shale hills" after the Bisti/De-Na-Zin Wilderness Area where the specimen was probably found + Latin tyrannus "ruler", common suffix for tyrannosauroids.  Greek anax "tribal chief or leader".
Alamo after the Ojo Alamo Formation where the material is from, in turn named for the Ojo Alamo trading post + Latin tyrannus "ruler", common suffix for tyrannosauroids. brinkmani probably from vertebrate paleontologist Donald B. Brinkman.
Late Campanian, Late Cretaceous
De-na-zin Member of Kirtland Formation?, San Juan Basin, New Mexico, US
Material
- ?(ACM 7975; intended syntype of "Alamotyrannus brinkmani") anterior right dentary (~142 mm deep) (Dalman, 2013)
Campanian-Maastrichtian, Late Cretaceous
San Juan Basin, New Mexico, US
?(PMU.R35; = PMU.R85 of Carr and Williamson, 2000 Appendix 1; = PMU.R1235 of Carr and Williamson, 2000 Fig. 9G-H and Appendix 1; intended syntype of "Alamotyrannus brinkmani"?) anterior right dentary (Sullivan and Williamson, 1997)
Comments- ACM 7975 was discovered in July or August 1924, and figured and briefly described by Dalman and Lucas (2016) as "Tyrannosauridae indeterminate" despite the authors listing two characters purportedly differentiating it from other tyrannosaurids.  Namely, "the possession of two foramina intermandibularis oralis" and "the morphology of the anterior step of the lingual bar" which "is anterodorsally inclined and has a relatively short posterior surface (towards the mouth), whereas in other tyrannosaurids (e.g., Daspletosaurus, Tarbosaurus, and Tyrannosaurus) the posterior surface of the step is well-developed and nearly the same length as the dorsal surface."
Dalman (2013) stated "the many isolated but diagnostic tyrannosaurid skeletal fossil elements from the Naashoibito Member of the Ojo Alamo Formation (early Maastrichtian) of northwestern New Mexico (Sullivan et al. 2005; Jasinski et al. 2011; Dalman and Lucas, in press) provide evidence for the occurrence of a new taxon of a large tyrannosaurid" with the in press paper's bibliographic entry naming it "Alamotyrannus brinkmani." Stuchlik (pers. comm. to Dalman, 7-2018) informs me the intended holotype was two dentaries, presumedly including ACM 7975 that was mentioned in Dalman (2013) as "the new Ojo Alamo tyrannosaurid taxon ACM 7975." Dalman (pers. comm. to Demirjian, 2015) stated the paper is postponed as more complete remains were discovered, and that the taxon would receive a different name.  A probable explanation is that Dalman and Lucas (2016) briefly described and figured ACM 7975 as a diagnostic tyrannosaurid under study by Dalman but noted that the previous referral to the Ojo Alamo Formation was due to its discoverer Loomis using an old, broader definition for the formation.  Geographical and preservational data indicated instead that ACM 7975 was probably from the De-na-zin Member of the Kirtland Formation, so mixing it with the diagnostic Ojo Alamo elements noted by Dalman (2013) would make his "Alamotyrannus" concept a chimaera.  Thus Dalman would want to describe the diagnostic Kirtland dentary and the diagnostic Ojo Alamo elements as different taxa, which seems to be the plan based on his 2024 online curriculum vitae. 
This lists "Dalman, S.G., Jasinski, S.E., Lucas, S.G., Malinzak, D.E., Loewen, M.A., Fiorillo, A.R., Currie, P.J. 2024. Bistityrannus anax, a new tyrannosaurid from the Kirtland Formation (Upper Cretaceous) of northwestern New Mexico. Cretaceous Research (in review/in progress)" under Published Research despite being unpublished as of 9-21-2024.  The genus and species are obviously invalid pending this publication as his online curriculum vitae is not "issued for the purpose of providing a public and permanent scientific record" (IZCN Article 8.1.1), "produced in an edition containing simultaneously obtainable copies by a method that assures 8.1.3.1. numerous identical and durable copies (see Article 8.4), or 8.1.3.2. widely accessible electronic copies with fixed content and layout" (Article 8.1.3), does not "state the date of publication in the work itself, and" is not "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" (Articles 8.5.2 and 8.5.3), the taxa are not "accompanied by a description or definition that states in words characters that are purported to differentiate the taxon" (Article 13.1) or "explicitly indicated as intentionally new" (Article 16.1).
Another unpublished entry on that page with identical authorship is "Denazinosaurus sicarius, a new tyrannosaurid from the Kirtland Formation (De-na-zin Member) Upper Cretaceous of New Mexico, USA", giving us two proposed new Kirtland tyrannosaurids with nothing distinguishing them in their publication titles besides "Denazinosaurus" definitely being from the De-na-zin Member.  While either or neither of these could be intended for former "Alamotyrannus" dentary ACM 7975, it's here suggested the stratigraphic uncertainty behind that specimen's discovery makes De-Na-Zin unlikely to feature in the article title or genus name.  Thus ACM 7975 is probably "Bistityrannus", while "Denazinosaurus" would be a different specimen with a more definite locality.  Given most De-Na-Zin tyrannosaurid specimens are isolated teeth and postcrania (generally considered indeterminate in Tyrannosauridae), that ideally Dalman would want a specimen comparable to ACM 7975 to erect a new contemporaneous species distinct from it, and that he is describing other tyrannosaurids based on dentaries (see Fruitland Formation KU VP-96888), the obvious identity of "Denazinosaurus" would be classic dentary USNM V 8346 described by Gilmore in 1916 (see entry).  Whether this logic proves true awaits either publication. 
Interestingly, given Dalman originally intended to name "Alamotyrannus" based on two dentary syntypes including ACM 7975, it implies a second tyrannosaur dentary plausibly from the Ojo Alamo Formation.  While NMMNH P-7199 is an obvious possibility as the only dentary I know of confirmed from that formation, it's so poorly preserved that it's never even been figured.  I propose a more likely possibility is anterior dentary PMU.R35 whose locality can only be specified to San Juan County, and which seems to have the anterior step morphology described for ACM 7975- anterodorsally inclined with a short posterior surface (Sullivan and Williamson, 1997- Fig. 1D).  As its uncertain stratigraphic placement makes it plausibly from the De-Na-Zin Member, this may be an additional specimen of "Bistityrannus".  Discovered in 1921 or 1922, this was not published until Sullivan and Williamson's 1997 review of PMU specimens sent by Sternberg, where it is figured in lateral and medial views as "tyrannosaurid partial right dentary." 
References- Sullivan and Williamson, 1997. Additions and corrections to Sternberg's San Juan Basin Collection, Paleontological Museum, University of Uppsala, Sweden. New Mexico Geological Society Guidebook, 48th Field Conference, Mesozoic Geology and Paleontology of the Four Corners Region. 255-257.
Carr and Williamson, 2000. A review of Tyrannosauridae (Dinosauria: Coelurosauria) from New Mexico. In Lucas and Heckert (eds.). Dinosaurs of New Mexico. New Mexico Museum of Natural History and Science. Bulletin. 17, 113-146.
Dalman, 2013. New examples of Tyrannosaurus rex from the Lance Formation of Wyoming, United States. Bulletin of the Peabody Museum of Natural History. 54(2), 241-254.
Dalman and Lucas, 2016.  Frederic Brewster Loomis and the 1924 Amherst College paleontological expedition to the San Juan Basin, New Mexico. New Mexico Museum of Natural History and Science Bulletin. 74, 61-66.
Dalman, 2024 online. https://www.montana.edu/earthsciences/graduate-program/students/cv/Sebastian_Dalman.html
Dalman and Lucas, "in press". A new large tyrannosaurid Alamotyrannus brinkmani, n. gen., n. sp. (Theropoda: Tyrannosauridae), from the Upper Cretaceous Ojo Alamo Formation (Naashoibito Member), San Juan Basin, New Mexico. New Mexico Museum of Natural History and Science Bulletin.
Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review a. Denazinosaurus sicarius, a new tyrannosaurid from the Kirtland Formation (De-na-zin Member) Upper Cretaceous of New Mexico, USA. Acta Palaeontologica Polonica.
Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review b. Bistityrannus anax, a new tyrannosaurid from the Kirtland Formation (Upper Cretaceous) of northwestern New Mexico. Cretaceous Research.

"Denazinosaurus" Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review in Dalman, online 2024
"D. sicarius" Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review in Dalman, online 2024
Etymology- De-Na-Zin is Navajo for "cranes" and presumedly based on the De-na-zin Member of the Kirtland Formation which the taxon would be from + Greek sauros "reptile." Latin sicarius "assassin", as it's a probable hunter.
Late Campanian, Late Cretaceous
head of Hunter Wash / locality 60 of Bauer 1916, De-na-zin Member of Kirtland Formation, San Juan County, New Mexico, US

Material- ?(USNM V 8346) incomplete left dentary (tooth row length 354 mm) (Gilmore, 1916)
Comments- Discovered August 20, 1915, this was initially described by Gilmore (1916) as "Deinodon?" and figured in medial view.  He noted "In the number of tooth sockets this jaw agrees with Dynamosaurus imperosus Osborn,a [now Tyrannosaurus rex] but in the general form of the dentary, particularly the contour of the anterior end, it approaches Albertosaurus4 (Dryptosaurus) most nearly, but as the dentary of Albertosaurus has sockets for 15 teeth the presence of 13 in this individual would appear to show its distinctness."  Gilmore further stated "It is quite possible that this dentary pertains to the genus Deinodon, but that can not be determined at this time because the dentary of that genus is unknown. The identification of this specimen must therefore await the discovery of additional material."  Gilmore (1920) repeated most of this verbatim, listing it as "DEINODON, species." this time.  In a later publication, Gilmore (1935) wrote "Comparison of this bone directly with a dentary of Gorgosaurus libratus Lambe from the Belly River of Canada now shows such close resemblances in size, shape, and other characteristics down to the smallest details as to leave little doubt of their being congeneric. Likewise, the number of alveoli (13) is in agreement with Lambe’s (1917) determination from a number of specimens that the dentary in this genus bears 13 or 14 teeth."  Lucas et al. (1987) felt the dentary "almost certainly pertain[s] to Albertosaurus" sensu Russell 1970, equating to modern Albertosaurinae.  Carr and Williamson (2000) figured the dentary in lateral, medial and dorsal views, and stated "Based on personal observation of this and other tyrannosaurid dentaries, this bone does not appear to be diagnostic at the specific or generic levels."  They noted "There are actually 14 dental alveoli" and concluded "Because the alveolus count of USNM 8346 overlaps with that of A. libratus and T. rex and in light of the fact that tooth count is variable in these species, we consider it best to consider this specimen as indeterminate Tyrannosauridae."  Indeed, 14 dentary alveoli are also present in some Albertosaurus sarcophagus (AMNH 5222, TMP 1986.064.0001), Daspletosaurus torosus (CMN 8506) and Tarbosaurus (IGM 107/7) specimens. 
Dalman's 2024 online curriculum vitae lists "Dalman, S.G. Jasinski, S.E., Lucas, S.G., Malinzak, D.E., Loewen, M.A., Fiorillo, A.R. and Currie, P.J. 2024. Denazinosaurus sicarius, a new tyrannosaurid from the Kirtland Formation (De-na-zin Member) Upper Cretaceous of New Mexico, USA. Acta Palaeontologica Polonica (in review/in progress)" under Published Research despite being unpublished as of 9-21-2024.  The genus and species are obviously invalid pending this publication as his online curriculum vitae is not "issued for the purpose of providing a public and permanent scientific record" (IZCN Article 8.1.1), "produced in an edition containing simultaneously obtainable copies by a method that assures 8.1.3.1. numerous identical and durable copies (see Article 8.4), or 8.1.3.2. widely accessible electronic copies with fixed content and layout" (Article 8.1.3), does not "state the date of publication in the work itself, and" is not "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" (Articles 8.5.2 and 8.5.3), the taxa are not "accompanied by a description or definition that states in words characters that are purported to differentiate the taxon" (Article 13.1) or "explicitly indicated as intentionally new" (Article 16.1).
Another unpublished entry on that page with identical authorship is "Bistityrannus anax, a new tyrannosaurid from the Kirtland Formation (Upper Cretaceous) of northwestern New Mexico", giving us two proposed new Kirtland tyrannosaurids with nothing distinguishing them in their publication titles besides "Denazinosaurus" definitely being from the De-na-zin Member.  While either or neither of these could be intended for former "Alamotyrannus" dentary ACM 7975 (see "Bistityrannus" entry), it's here suggested the stratigraphic uncertainty behind that specimen's discovery makes De-Na-Zin unlikely to feature in the article title or genus name.  Thus ACM 7975 is probably "Bistityrannus", while "Denazinosaurus" would be a different specimen with a more definite locality.  Given most De-Na-Zin tyrannosaurid specimens are isolated teeth and postcrania (generally considered indeterminate in Tyrannosauridae), that ideally Dalman would want a specimen comparable to ACM 7975 to erect a new contemporaneous species distinct from it, and that he is describing other tyrannosaurids based on dentaries (see Fruitland Formation KU VP-96888), the obvious identity of "Denazinosaurus" would be classic dentary USNM V 8346.  Whether this logic proves true awaits either publication.
References- Gilmore, 1916. Vertebrate faunas of the Ojo Alamo, Kirtland and Fruitland formations. United States Geological Survey, Professional Paper. 98Q, 279-308.
Gilmore, 1920. Osteology of the carnivorous Dinosauria in the United States National Museum, with special reference to the genera Antrodemus (Allosaurus) and Ceratosaurus. Bulletin of the United States National Museum. 110, 1-154.
Gilmore, 1935. On the Reptilia of the Kirtland Formation of New Mexico, with descriptions of new species of fossil turtles. Proceedings of the United States National Museum. 83(2978), 159-188.
Lucas, Mateer, Hunt and O'Neill, 1987. Dinosaurs, the age of the Fruitland and Kirtland Formations, and the Cretaceous-Tertiary boundary in the San Juan Basin, New Mexico. In Fassett and Rigby (eds.). The Cretaceous-Tertiary Boundary in the San Juan and Raton Basins, New Mexico and Colorado. Geological Society of America Special Paper. 209, 35-50.
Carr and Williamson, 2000. A review of Tyrannosauridae (Dinosauria: Coelurosauria) from New Mexico. In Lucas and Heckert (eds.). Dinosaurs of New Mexico. New Mexico Museum of Natural History and Science. Bulletin. 17, 113-146.
Dalman, 2024 online. https://www.montana.edu/earthsciences/graduate-program/students/cv/Sebastian_Dalman.html
Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review a. Denazinosaurus sicarius, a new tyrannosaurid from the Kirtland Formation (De-na-zin Member) Upper Cretaceous of New Mexico, USA. Acta Palaeontologica Polonica.
Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review b. Bistityrannus anax, a new tyrannosaurid from the Kirtland Formation (Upper Cretaceous) of northwestern New Mexico. Cretaceous Research.

"Erinotonax" Dalman, Jasinski, Loewen, Malinzak, Currie, Fiorillo and Lucas, in progress/review in Dalman, online 2024
"E. sabathi" Dalman, Jasinski, Loewen, Malinzak, Currie, Fiorillo and Lucas, in progress/review in Dalman, online 2024
Etymology- Perhaps Greek Eri "very" + Greek notos "south" + Greek anax "king" (suggested by Creisler, pers. comm. 9-2024). sabathi after paleontologist Karol Sabath.
Late Campanian, Late Cretaceous
Ne-nah-ne-zad Member, Fruitland Formation, San Juan Basin, New Mexico, US

Material- ?(KU VP-96888) (~10 m) anterior left dentary (140 mm deep) (Dalman and Lucas, 2021)
Comments- Dalman and Lucas (2021) state "The specimen is being described by us in detail in another paper as belonging to a new genus and a new species" but contradictorally identify it as "Tyrannosauridae indet."  They also say "When compared to the dentaries of other tyrannosaurids such as Albertosaurus, Bistahieversor, Daspletosaurus, Gorgosaurus, Lythronax, Tarbosaurus, Teratophoneus and Tyrannosaurus, the body length of KUVP-96888 was close to 10 m."  This is listed as Tyrannosaurus sp. in the KU online catalog.
Coincidentally, Dalman's 2024 online curriculum vitae lists "Dalman, S.G., Jasinski, S.E., Loewen, M.A., Malinzak, D.E., Currie, P.J., Fiorillo, A.R., Lucas, S.G. 2024. Erinotonax sabathi, a new tyrannosaurid from the Fruitland Formation (Upper Cretaceous) of New Mexico, USA, insights into the evolution, diversity, and paleogeography of tyrannosaurids in North America. PeerJ (in review/in progress)" despite being unpublished as of 9-21-2024.  The genus and species are obviously invalid pending this publication as his online curriculum vitae is not "issued for the purpose of providing a public and permanent scientific record" (IZCN Article 8.1.1), "produced in an edition containing simultaneously obtainable copies by a method that assures 8.1.3.1. numerous identical and durable copies (see Article 8.4), or 8.1.3.2. widely accessible electronic copies with fixed content and layout" (Article 8.1.3), does not "state the date of publication in the work itself, and" is not "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" (Articles 8.5.2 and 8.5.3), the taxa are not "accompanied by a description or definition that states in words characters that are purported to differentiate the taxon" (Article 13.1) or "explicitly indicated as intentionally new" (Article 16.1).
Unless Dalman and Lucas are describing multiple new genera of tyrannosaurids from the Fruitland Formation, it seems likely "Erinotonax" is KU VP-96888.  Given its fragmentary and pathological condition, I'm skeptical of any future diagnosis.
References- Dalman and Lucas, 2021. New evidence for cannibalism in tyrannosaurid dinosaurs from the Upper Cretaceous (Campanian/Maastrichtian) San Juan Basin of New Mexico. New Mexico Museum of Natural History and Science Bulletin. 82, 39-56.
Dalman, 2024 online. https://www.montana.edu/earthsciences/graduate-program/students/cv/Sebastian_Dalman.html
Dalman, Jasinski, Loewen, Malinzak, Currie, Fiorillo and Lucas, in progress/review. Erinotonax sabathi, a new tyrannosaurid from the Fruitland Formation (Upper Cretaceous) of New Mexico, USA, insights into the evolution, diversity, and paleogeography of tyrannosaurids in North America. PeerJ.

"Atroxicarius" Dalman, Jasinski, Loewen, Lucas, Malinzak, Fiorillo and Currie, in progress/review in Dalman, online 2024
"A. eversor" Dalman, Jasinski, Loewen, Lucas, Malinzak, Fiorillo and Currie, in progress/review in Dalman, online 2024
Etymology- Latin atrox "fierce" + ? Latin arius "agent of use", except the 'c' is unexplained and atrox is not a noun. Creisler (pers. comm 9-2024) suggests atrox + Latin cara "head" + Latin suffix -ius, but that should imply cranial remains which are not at all certain. Greek eversor "destroyer."
Late Maastrichtian, Late Cretaceous
NMMNH L-3961, Naashoibito Member of Ojo Alamo Formation, San Juan County, New Mexico, US

?(NMMNH P-7199) partial left dentary, 113 tooth fragments, partial vertebra (Carr and Williamson, 2000)
Late Maastrichtian, Late Cretaceous
SMP 313b, Naashoibito Member of Ojo Alamo Formation, Hunter Wash, San Juan County, New Mexico, US
?(SMP VP-1848) incomplete left metatarsal I (~93 mm) (Jasinski, Sullivan and Lucas, 2011)
Late Maastrichtian, Late Cretaceous
SMP 371, Naashoibito Member of Ojo Alamo Formation, Betonnie Tsosie Wash, San Juan County, New Mexico, US

?(SMP VP-1113) incomplete right femur (~1 m) (Carr and Williamson, 2000)
Late Maastrichtian, Late Cretaceous
SMP 424b, Naashoibito Member of Ojo Alamo Formation, San Juan Basin, New Mexico, US
?(SMP VP-2105) incomplete right scapulocoracoid (coracoid ~253 mm proximodist) (Jasinski, Sullivan and Lucas, 2011)
Late Maastrichtian, Late Cretaceous
Naashoibito Member of Ojo Alamo Formation, San Juan County, New Mexico, US
?(Ratkevich coll.) right metatarsal IV (~513 mm) (Lehman, 1981)
Late Maastrichtian, Late Cretaceous
Naashoibito Member of Ojo Alamo Formation, San Juan Basin, New Mexico, US

?(AMNH 5882) right pedal phalanx IV-2 (~143 mm) (Carr and Williamson, 2000)
Comments
- Discovered May 7, 1998, NMMNH P-7199 is a partial dentary associated with tooth fragments and a partial vertebra that all remain unfigured.  Carr and Williamson (2000) refer it "to cf. T. rex on the basis of its large apical and midheight denticles, 7.5 denticles per 5 mm and 8.5 denticles per 5 mm, respectively" on the mesial carina and note the dentary and vertebra "are too weathered and incomplete to permit identification."  Jasinski et al. (2011) suggested however that "identification below the family level (Tyrannosauridae) based on denticle densities is tenuous" so retained it as Tyrannosauridae indet..  The NMMNH online catalog incorrectly lists this as being from the De-na-zin Member of the Kirtland Formation.
Jasinski et al. (2011) notes "The scapulocoracoid (SMP VP-2105, Fig. 7A-B) may be from an adult as it compares readily in size and morphology to the scapulocoracoids of Tyrannosaurus rex (FMNH PR2081; Brochu, 2003, fig. 80). While this indicates the presence of a large tyrannosaurid in the Naashoibito Member, the specimen cannot be confidently referred to Tyrannosaurus rex, but may represent Tyrannosaurus sp."
Femur SMP VP-1113 is first published as "SMP VP-? femur Naashoibito Mbr., Kirtland Fm. Tyrannosauridae indet" by Carr and Williamson (2000), then figured by Lucas and Sullivan (2000) as "Tyrannosauridae, incomplete femur."  Sullivan et al. (2005) identified it as "cf. Daspletosaurus sp., based on comparison with USNM 10754, a right femur of either Gorgosaurus or Daspletosaurus sp. (labelled as Albertosaurus sp.) ... from the Dinosaur Park Formation" because "the size and morphology of SMP VP-1113 closely resembles that of USNM 10754", but the only stated character is gracility compared to Tyrannosaurus, which is true for almost all other tyrannosaurids.
Jasinski et al. (2011) figure a metatarsal I (incorrectly called "the 1st phalanx of the 1st metatarsal" on page 226), which along with femur SMP VP-1113 they state is "from a large tyrannosaurid that seems more gracile than an adult Tyrannosaurus rex, although they may represent a juvenile or sub-adult."
Lehman (1981) wrote "single, complete, right fourth metatarsal (on loan from the collection of Ronald P. Ratkevich of Alamogordo, New Mexico) is tentatively referred here to Albertosaurus sp." using the broad concept of the genus popular at the time where it included Gorgosaurus.  It is figured in anterior, medial and five sectional views.
Carr and Williamson (2000) reported "a large pedal phalanx (AMNH 5882; Fig. 4A-F) was collected from the Naashoibito Member of the Kirtland Formation. The collector and date of collection of this specimen are unknown" and figured it in multiple views as Tyrannosauridae indet..  Oddly, the AMNH online catalog lists this as being collected by Brown from the Hell Creek Formation of Snow Creek, Montana, but does correctly list it as a "2nd phalanx" of Theropoda.  Williamson and Carr (2005) referred the phalanx to cf. Tyrannosaurus rex in an abstract.
"Alamotyrannus" into "Atroxicarius"- Dalman (2013) stated "the many isolated but diagnostic tyrannosaurid skeletal fossil elements from the Naashoibito Member of the Ojo Alamo Formation (early Maastrichtian) of northwestern New Mexico (Sullivan et al. 2005; Jasinski et al. 2011; Dalman and Lucas, in press) provide evidence for the occurrence of a new taxon of a large tyrannosaurid" with the in press paper's bibliographic entry naming it "Alamotyrannus brinkmani." Stuchlik (pers. comm. to Dalman, 7-2018) informs me the intended holotype was two dentaries, presumedly including ACM 7975 that was mentioned in Dalman (2013) as "the new Ojo Alamo tyrannosaurid taxon ACM 7975." Dalman (pers. comm. to Demirjian, 2015) stated the paper is postponed as more complete remains were discovered, and that the taxon would receive a different name.  A probable explanation is that Dalman and Lucas (2016) briefly described and figured ACM 7975 as a diagnostic tyrannosaurid under study by Dalman but noted that the previous referral to the Ojo Alamo Formation was due to its discoverer Loomis using an old, broader definition for the formation.  Geographical and preservational data indicated instead that ACM 7975 was probably from the De-na-zin Member of the Kirtland Formation, so mixing it with the diagnostic Ojo Alamo elements noted by Dalman (2013) would make his "Alamotyrannus" concept a chimaera.  Thus Dalman would want to describe the diagnostic Kirtland dentary and the diagnostic Ojo Alamo elements as different taxa, which seems to be the plan based on his 2024 online curriculum vitae. 
This lists "Dalman, S.G., Jasinski, S.E., Loewen, M.A., Lucas, S.G., Malinzak, D.E., Fiorillo, A.R., and Currie, P.J. 2024. Atroxicarius eversor, a new tyrannosaurid from the Ojo Alamo Formation (Upper Cretaceous) of New Mexico, USA, new insights into the evolution of bistahiversorin tyrannosaurids in North America. Anatomical Records (in review/in progress)" under Published Research despite being unpublished as of 9-21-2024 and presumedly referring to The Anatomical Record.  This would then seem to be the new name of the Ojo Alamo tyrannosaurid, which the title suggests is related to Bistahieversor in a new tribe "Bistahieversorini", although note Dalman misspelled it without the first 'e'. The tribe, genus and species are obviously invalid pending this publication as his online curriculum vitae is not "issued for the purpose of providing a public and permanent scientific record" (IZCN Article 8.1.1), "produced in an edition containing simultaneously obtainable copies by a method that assures 8.1.3.1. numerous identical and durable copies (see Article 8.4), or 8.1.3.2. widely accessible electronic copies with fixed content and layout" (Article 8.1.3), does not "state the date of publication in the work itself, and" is not "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" (Articles 8.5.2 and 8.5.3), the taxa are not "accompanied by a description or definition that states in words characters that are purported to differentiate the taxon" (Article 13.1) or "explicitly indicated as intentionally new" (Article 16.1) and even a correctly spelled "bistahieversorine" is not in Latinized form (article 11.7.2) nor is it "accompanied by citation of the name of the type genus" (Article 16.2).  Based on another Dalman et al. (in review/progress) citation in Dalman's curriculum vitae, the De-na-zin tyrannosaurid will be named "Denazinosaurus sicarius" and preseumedly includes dentary ACM 7975 as the intended holotype.
It's unknown which specimens will be types of "Atroxicarius", but as Dalman (2013) cited skeletal (not dental, which are generally undiagnostic) elements described by Sullivan et al. (2005) and Jasinski et al. (2011), they plausibly include dentary and vertebra NMMNH P-7199, scapulocoracoid SMP VP-2105, femur SMP VP-1113, metatarsal I SMP VP-1848, a metatarsal IV from the private Ratkevich collection, and/or pedal phalanx AMNH 5882. 
References- Lehman, 1981. The Alamo Wash local fauna: A new look at the old Ojo Alamo fauna. In Lucas, Rigby and Kues (eds.). Advances in San Juan Basin paleontology. University of New Mexico Press. 189-221.
Carr and Williamson, 2000. A review of Tyrannosauridae (Dinosauria: Coelurosauria) from New Mexico. In Lucas and Heckert (eds.). Dinosaurs of New Mexico. New Mexico Museum of Natural History and Science. Bulletin. 17, 113-146.
Lucas and Sullivan, 2000. Stratigraphy and vertebrate biostratigraphy across the Cretaceous-Tertiary boundary, Betonnie Tsosie Wash, San Juan Basin, New Mexico. New Mexico Museum of Natural History and Science Bulletin. 17, 95-103.
Sullivan, Luvas and Braman, 2005. Dinosaurs, pollen, and the Cretaceous-Tertiary boundary in the San Juan Basin, New Mexico. New Mexico Geological Society, 56th Field Conference Guidebook, Geology of
the Chama Basin. 56, 395-407.
Williamson and Carr, 2005. Latest Cretaceous tyrannosaurs from the San Juan Basin, New Mexico. Abstracts of Proceedings from "100 years of Tyrannosaurus rex, a Symposium." 38.
Jasinski, Sullivan and Lucas, 2011. Taxonomic composition of the Alamo Wash local fauna from the Upper Cretaceous Ojo Alamo Formation (Naashoibito Member), San Juan Basin, New Mexico. In Sullivan, Lucas and Spielmann (eds.). Fossil Record 3. New Mexico Museum of Natural History and Science Bulletin. 53, 216-271.
Dalman, 2013. New examples of Tyrannosaurus rex from the Lance Formation of Wyoming, United States. Bulletin of the Peabody Museum of Natural History. 54(2), 241-254.
Dalman and Lucas, 2016.  Frederic Brewster Loomis and the 1924 Amherst College paleontological expedition to the San Juan Basin, New Mexico. New Mexico Museum of Natural History and Science Bulletin. 74, 61-66.
Dalman, 2024 online. https://www.montana.edu/earthsciences/graduate-program/students/cv/Sebastian_Dalman.html
Dalman and Lucas, "in press". A new large tyrannosaurid Alamotyrannus brinkmani, n. gen., n. sp. (Theropoda: Tyrannosauridae), from the Upper Cretaceous Ojo Alamo Formation (Naashoibito Member), San Juan Basin, New Mexico. New Mexico Museum of Natural History and Science Bulletin.
Dalman, Jasinski, Loewen, Lucas, Malinzak, Fiorillo and Currie, in progress/review. Atroxicarius eversor, a new tyrannosaurid from the Ojo Alamo Formation (Upper Cretaceous) of New Mexico, USA, new insights into the evolution of bistahiversorin tyrannosaurids in North America. The Anatomical Record.
Dalman, Jasinski, Lucas, Malinzak, Loewen, Fiorillo and Currie, in progress/review. Denazinosaurus sicarius, a new tyrannosaurid from the Kirtland Formation (De-na-zin Member) Upper Cretaceous of New Mexico, USA. Acta Palaeontologica Polonica.


But we also have a few other nomina nuda based on early versions of papers.

Fujianvenator Xu, Wang, Chen, Dong, Lin, Xu, Tang, You, Zhou, Wang, He, Li, Zhang and Zhou, 2023
F. prodigiosus Xu, Wang, Chen, Dong, Lin, Xu, Tang, You, Zhou, Wang, He, Li, Zhang and Zhou, 2023
= Fujianvenator "rapidus" Xu, Wang, Chen, Dong, Lin, Xu, Tang, You, Zhou, Wang, He, Li, Zhang and Zhou, 2023
Etymology- The apparent early species name "rapidus" is no doubt from Latin rapidus "quick", as the authors state "Fujianvenator was well adapted for terrestrial locomotion and is likely to have been capable of running at a high speed."
Comments- Xu et al.'s (2023) reporting summary states "The holotype of Fujianvenator rapidus (IVPP V31985) was discovered in Daxi Basin near Yangyuan Village, Zhenghe Country, Nanping City, Fujian Province, Southeast China" three times, making this a likely early name for F. prodigiosus.
Reference- Xu, Wang, Chen, Dong, Lin, Xu, Tang, You, Zhou, Wang, He, Li, Zhang and Zhou, 2023. A new avialan theropod from an emerging Jurassic terrestrial fauna. Nature. 621, 336-343.

Hypnovenator Kubota, Kobayashi and Ikeda, 2024
H. matsubaraetoheorum Kubota, Kobayashi and Ikeda, 2024
= Hypnovenator "sasayamaensis" Kubota, Kobayashi and Ikeda, 2024 online
Etymology- "The specific name, "sasayama", refers to previous name of a city placed in the eastern region of Hyogo Prefecture, from where the holotype specimen was collected. It also refers to an amateur group "Association to Study the Sasayama Group", to which the two discovers belong."
Comments- The species name "sasayamaensis" was used in the preprint of the article.
References- Kubota, Kobayashi and Ikeda, 2024 online. Early Cretaceous troodontine troodontid (Dinosauria: Theropoda) from the Ohyamashimo Formation of Japan reveals the early evolution of Troodontinae. Research Square preprint. DOI: 10.21203/rs.3.rs-4459611/v1
Kubota, Kobayashi and Ikeda, 2024. Early Cretaceous troodontine troodontid (Dinosauria: Theropoda) from the Ohyamashimo Formation of Japan reveals the early evolution of Troodontinae. Scientific Reports. 14:16392.

Daspletosaurus wilsoni Warshaw and Fowler, 2022
= Daspletosaurus "diadematus" Warshaw, Wilson and Fowler, 2022 online
Etymology- "Diadematus, Latin for “crowned,” in reference to the novel postorbital horn morphology unique to this species, and its diagnosis as a tyrant dinosaur."
Comments- The initial manuscript called this D. "diadematus", which was replaced by wilsoni after its discoverer John Wilson was removed from the authorship.
References- Warshaw and Fowler, 2022. A transitional species of Daspletosaurus Russell, 1970 from the Judith River Formation of eastern Montana. PeerJ. 10:e14461.
Warshaw, Wilson and Fowler, 2022 online. A transitional species of Daspletosaurus Russell, 1970 from the Judith River Formation of eastern Montana. PeerJ reviewing PDF (2022:07:75847:0:1:NEW)

Sunday, June 23, 2024

Fonseca et al (2024) perform a Lori-style analysis of basal Ornithischia

This post is a shout-out to Fonseca et al. (2024), whose abstract states-

"Resolving the evolutionary relationships of early diverging (‘basal’) ornithischian dinosaurs is a challenging topic in palaeontology, with multiple competing hypotheses on the phylogenetic relationships of heterodontosaurids, ‘hypsilophodontids’, and other early-diverging forms. These hypotheses cannot be directly compared because they are derived from differently constructed datasets (i.e. distinct samples of taxa and characters). This study aims to address these issues by revising and combining the distinct datasets into a single analysis in order to create the most comprehensive dataset for the investigation of the phylogenetic relationships of early-diverging ornithischians."

This is the ideal for a phylogenetic analysis and exactly what I attempted for Lori, providing some useful data.  They write "constrained analysis forcing a close affinity between Heterodontosauridae and Marginocephalia require at least 26 extra steps, while joining them and Pachycephalosauria require at a minimum 44 steps", so those are implausible.  The weird little bipedal armored Jakapil comes out sister to Eurypoda, and "enforcing it as a marginocephalian requires 16 additional steps" so is unlikely.  Making it parankylosaurian requires only 4 steps though, so is quite likely and matches geographically.  For as much crap as I gave Norman's phylogenetic nomenclature, his Hypsilophodontia including Tenontosaurus (and other rhabdodontomorphs) only takes 6 more steps, so is less likely but not bad.  While Fonseca et al.'s main results are interesting, I found the supplementary information where they commented on all the taxa they excluded equally informative.

Teeth of Ferganocephale adenticulatum- A-B paratype ZIN PH 31/42; C-F holotype ZIN PH 34/32; G-J paratype ZIN PH 36/42; K-N paratype ZIN PH 33/42. Apical- A, C, G, N; Mesial or distal- B, E, I, L; Labial or lingual- D, F, H, J, K, M. After Averianov et al., 2005.


"Ferganocephale adenticulatum Averianov et al. (2005) displays no ankylothecodonty (ch388:0), low crowns (ch411:0), round crown apices (ch413:1), no apicobasal ridges (ch421:0), an asymmetric labiolingual expansion (ch422:1), a cingulum (ch423:1), and no denticles. While these features show the most similarity to Chaoyangsauridae, the lack of denticles and strength of the cingulum are very different from the clade, so a classification as intermediate Saphornithischia is most likely. The position of Ferganocephale adenticulatum requires further work done to assess the dental morphologies within Pan-Aves as a whole, especially due to its un-archosauriform lack of denticulation (see Ezcurra, 2016)."

Holotype right maxilla of Lusitanosaurus liassicus in lateral view (University of Lisbon coll.; destroyed). After Lapparent and Zbyszewski, 1957.


"Lusitanosaurus liassicus Lapparent and Zbyszewski (1957) displays ankylothecodont teeth (ch388:1), low crowns (ch411:0), no recurvature (ch414:2), no apicobasal ridges (ch421:0), and no cingulum (ch423:0). The type specimen was lost in a fire (Mateus et al., 2022), so the only information available about the taxon is from the original description and plate of Lapparent and Zbyszewski (1957). The crowns are tricuspid, which is shared with members of Pterosauria (Dalla Vecchia, 2013), Squamata (Conrad, 2008), Tanystropheidae (Renesto & Dalla Vecchia, 2000; Spiekman et al., 2020), and basal Cynodontia (Hahn et al., 1984) but not Ornithischia. The lack of a cingulum also suggests Lusitanosaurus liassicus is not an ornithischian, as that was the only feature identified by Irmis et al. (2007) to distinguish early ornithischian teeth from similar but non-ornithischian phyllodont teeth. While it has been previously excluded from studies as a dubious basal thyreophoran (Antunes & Mateus, 2003; Norman et al., 2004a; Norman, 2020c), the distribution of anatomy instead suggests that Lusitanosaurus liassicus cannot be considered an ornithischian and should instead be considered Archosauromorpha indeterminate on the basis of ankylothecodont tooth implantation."

Teeth of Taveirosaurus costai- A paratype TV 16; B paratype TV 11; C paratype 14; D-E, J-K holotype TV 10; F paratype TV 8; G paratype TV 7; H paratype TV 13; I paratype TV 9. Lingual- A-D, F-J; Labial- E, K. After Antunes and Sigogneau-Russell, 1991.


"Taveirosaurus costai Antunes and Sigogneau-Russell (1991) displays cheek tooth crowns without mesial and distal ‘kinks’ (ch412:0), low crown height (ch411:0), coarse denticles (ch416:2), and no cingulum (ch423:0), which would support a position just within or outside Ornithischia. However, the morphology of the crowns is very divergent from ornithischians, and the only features linking the taxon with Ornithischia are also found in non-ornithischian archosauromorphs (Irmis et al., 2007), mammaliforms (Luo et al., 2002) and even hybodontiformes (Stumpf et al., 2022). Taveirosaurus costai is considered to belong to Eutriconodonta here on the basis of linear molar cusps and a distinct, straight cingulum (Luo et al., 2002) as well as its Late Cretaceous age, until further work is done to establish possible shared dental morphology with Ornithischia."

Holotype tooth of Trimucrodon cuneatus (Lehrstuhl für Paläontologie coll.). Lingual- a; Labial- b. After Thulborn, 1973.


"Trimucrodon cuneatus Thulborn (1973) displays sporadic wear facets (ch407:0), low crowns (ch411:0), kinked mesial and distal crown edges (ch412:1), triangular crown apices (ch413:0), no recurvature (ch414:2), mesiodistal expansion above the root (ch415:1), no apicobasal ridges (ch421:0), symmetric labiolingual expansion (ch422:0), and no cingulum (ch423:0). These features show significant conflict, especially the lack of a cingulum and asymmetrical labiolingual swelling which are exclusive synapomorphies of Parapredentata except for clades that are excluded for other characters (eg. lack of apicobasal ridges). Until further work is done to assess the dental morphologies within Pan-Aves as a whole, Trimucrodon cuneatus should be retained as a possibly valid taxon that cannot be classified beyond Ornithischia outside Parapredentata."

Several taxa like Alocodon, Phyllodon and Xiaosaurus are considered valid despite generally being ignored due to being fragmentary.  They even include a large supplement illustrating their characters, and justifying which characters were not included.  And you can tell they went up to the submission limit by commenting on recent taxa like Vectidromeus and Chakisaurus.

Things I wish Fonseca et al. would have done are list the possible positions of the taxa excluded WISELY a posteriori- "Daemonosaurus chauliodus; Diodorus scytobrachion; Gamatavus antiquus; Sacisaurus agudoensis; Mymoorapelta maysi; Nevadadromeus schmitti; Hualianceratops wucaiwaneisis; Beg tse; Ceratops montanus; the ‘Vegagete ornithopod’; Weewarrasaurus pobeni; Atlascopcosaurus loadsi; Galleonosaurus dorisae; Leaellynasaura amicagraphica; Qantassaurus intrepidus; Trinisaura santamartaensis; Isasicursor santacrucensis; Sektensaurus sanjuanboscoi; Callovosaurus leedsi; and Draconyx loureiroi", and scorings for the excluded taxa like Vectidromeus and "Hypsilophodon" wielandi.  Also more constraint analyses for things like the position of Lesothosaurus and Albalophosaurus (here the earliest pachycephalosaur).

Now we need someone to do this for the 30+ incertae sedis sauropodomorph taxa everyone's ignored for over three decades since they were kicked out of Plateosaurus/Massospondylus/Euskelosaurus using Yates' matrix or something better.

References- Lapparent and Zbyszewski, 1957. Les dinosauriens du Portugal. Mémoires des Services Géologiques du Portugal, nouvelle série. 2, 1-63.

Thulborn, 1973. Teeth of ornithischian dinosaurs from the Upper Jurassic of Portugal. Memórias dos Serviços Geológicos de Portugal. 22, 89-134.

Antunes and Sigogneau-Russell, 1991. Nouvelles données sur les Dinosaures du Crétacé supérieur du Portugal. Comptes rendus de l'Académie des sciences. Série 2, Mécanique, Physique, Chimie, Sciences de l'univers, Sciences de la Terre. 313(1), 113-119.

Averianov, Martin and Bakirov, 2005. Pterosaur and dinosaur remains from the Middle Jurassic Balabansai Svita in the northern Fergana depression, Kyrgyzstan (central Asia). Palaeontology. 48(1), 135-155.

Fonseca, Reid, Venner, Duncan, Garcia and Müller, 2024. A comprehensive phylogenetic analysis on early ornithischian evolution. Journal of Systematic Palaeontology. 22(1), 2346577.

Saturday, May 4, 2024

Correct citations for Sinosauropteryx and Protarchaeopteryx

A quick one today based on the fact I just found out the entirety of Chinese Geology is free online.  Ji and Ji used it for their early Yixian feathered theropod descriptions in the 90s.  Back then getting Chinese papers in the West was not as easy as today, and as Sinosauropteryx and Protarchaeopteryx both got redescribed in Nature in 1998 and had their original descriptions translated by Downs in 2001 and uploaded to The Polyglot Paleontologist, I think most researchers never bothered to hunt down the Chinese originals.  But now that they're easily available, I've noticed everyone's been copying the incorrect citations in the Nature or Downs' papers, so this post is here to sort that out.



Sinosauropteryx

https://www.cgsjournals.com/article/id/zgdz_DIZI199610011

Note these mid-90s papers don't actually have English titles.  The first published was the original description of Sinosauropteryx, given by Chen et al. (1998) as-

Ji, Q. & Ji, S. A. On discovery of the earliest bird fossil in China and the origin of birds. Chinese Geol. 233, 30–33 (1996).

And by Downs' 2001 translation as-

Qiang Ji and Shu’an Ji. On the Discovery of the earliest fossil bird in China (Sinosauropteryx gen. nov.) and the origin of birds. Chinese Geology. Volume 233. 1996. pp. 30-33.

But the actual citation is-

Ji and Ji, 1996. 中国最早鸟类化石的发现及鸟类的起源. Chinese Geology. 23(10) (total issue 233), 30-32.

Chen et al.'s is closer, as Google Translate translates the Chinese title as "The discovery of the earliest bird fossils in China and the origin of birds", and it certainly doesn't say "Sinosauropteryx gen. nov." which would be "中华龙鸟属新属".  I'm curious to know if there was a page 33 that the Chinese Geology scanners missed, perhaps containing a figure like the last pages of the next two articles (since there are no figures in the paper otherwise).

Skull of NGMC 2124 (photo by Mortimer at the TMP in 1999).


https://www.cgsjournals.com/article/id/zgdz_DIZI199707010

A second paper describing supposed Sinosauropteryx specimen NGMC 2124 was published the following year, and sadly remains the only paper describing this unique taxon (recovered a couple weeks ago as a juvenile tyrannosauroid in Cau's ontomatrix).  Currie and Chen (2001) give the reference as-

Ji, Q., and Ji, S.-A. 1997b. Advances in the study of the avian Sinosauropteryx prima. Chinese Geology, 242: 30–32 (in Chinese).

And there's an HTML translation that was online (as of 2010) that gives it as-

Ji Qiang & Ji Shuan, Advances in Sinosauropteryx Research, Chinese Geology, 1997, 7, p. 30-32 and cover page 3.

But the actual citation is-

Ji and Ji, 1997. 中华龙岛(Sinosauropteryx) 化石研究新进展. Chinese Geology. 24(7) (total issue 242), 30-32, 49.

Google Translate translates the Chinese title to "New progress in the study of Sinosauropteryx fossils" which seems more accurate than Currie and Chen's as the species name is certainly never mentioned.



Protarchaeopteryx

https://www.cgsjournals.com/article/id/zgdz_DIZI199703012

Ji et al. (1998) give the reference as-

Ji, Q. & Ji, S. A. Protarchaeopterygid bird (Protarchaeopteryx gen. nov.)—fossil remains of archaeopterygids from China. Chinese Geol. 238, 38–41 (1997).

Downs' 2001 translation gives us-

Qiang Ji and Shu’an Ji. A Chinese archaeopterygian, Protarchaeopteryx gen. nov.. Geological Science and Technology (Di Zhi Ke Ji). Volume 238. 1997. pp. 38-41.

But the actual citation is-

Ji and Ji, 1997. 恩错祖鸟(Protarchaeopteryx gen. nov.) - 中国的始祖鸟类亿右. Chinese Geology. 24(3) (total issue 238), 38-41, 49.

The first four characters (恩错祖鸟) translate to Protarchaeopteryx, so "protarchaeopterygid" is an invention of Ji et al., made more obvious by the fact it was classified as an archaeopterygid in the paper.  The implied family 'Protarchaeopterygidae' has never been published so remains unofficial.  Google Translate gives the translation "Protarchaeopteryx gen. nov. - Archaeopteryx of China."

Center of Protarchaeoptery holotype.




Lingyuanornis

https://www.cgsjournals.com/article/id/zgdz_DIZI199903021

I think the only other dinosaur described in Chinese Geology is Lingyuanornis, an objective junior synonym of Liaoxiornis that may have been first cited in Western literature by Chiappe and Walker (2002) as-

Ji Q. and Ji S.-A. 1999. A new genus of the Mesozoic birds from Lingyuan, Liaoning, China. Chinese Geology 262:45–48.

As English titles were a thing by now, the actual citation is pretty similar-

Ji and Ji, 1999. A new genus of the Mesozoic birds from Lingyuan, Liaoning, China. Chinese Geology. 26(3) (total issue 262), 45-49.


The volume issue

One obvious difference in citations besides the titles and page numbers are the volume numbers, with most prior citations using what appears to be a single large number representing the issue perhaps all the way from 1954 when the journal started.  However, the format the Chinese Geology website has is one with volumes corresponding to year (from 1958 forward), then issues of a variable number within that year.  The HTML Ji and Ji 1997 'Sinosauropteryx' translation does give the issue number (7) correctly, but none of them cite the volume corresponding to the official website.  Notably, the latter includes photos of all the issue covers showing the issue format was there from the beginning.  Also interesting is that while the 1996-1998 papers themselves have no indication of a volume or issue, Lingyuanornis' does include both "总第262 期 中 自 地 质" and "1999 年第3 期", translating to "
Total Issue No. 262 China Geology" and "Issue No. 3, 1999".  Back in 2001 I assumed this meant volume 262 issue 3, but this is obviously not the case, and 26(3) and 262 are two different ways of referencing the same issue.  Counting back shows that the other three "total issues" are indeed 233, 242 and 238, although I'm not sure where in the issues people found these numbers and they're not very useful for navigating the archive.



References-
Chen, Dong and Zhen, 1998. An exceptionally well-preserved theropod dinosaur from the Yixian Formation of China. Nature. 391, 147-152.

Ji, Currie, Norell and Ji, 1998. Two feathered dinosaurs from northeastern China. Nature. 393, 753-761.

Currie and Chen, 2001. Anatomy of Sinosauropteryx prima from Liaoning, northeastern China. Canadian Journal of Earth Sciences. 38(12), 1705-1727.

Chiappe and Walker, 2002. Skeletal morphology and systematics of the Cretaceous Euenantiornithes (Ornithothoraces: Enantiornithes). In Chiappe and Witmer (eds.). Mesozoic Birds - Above the Heads of Dinosaurs. University of California Press. 240-267.

Sunday, December 31, 2023

The Avian Acetabulum: Feduccia grasping at straws

It's not every day that we get an article arguing against the dinosaurian origin of birds any more, with that consensus so strongly supported and many of its detractors being deceased.  But last week Feduccia published "The Avian Acetabulum: Small Structure, but Rich with Illumination and Questions", so in the spirit of the Dinosaur Mailing List of the early 2000s, let's have a fun critique of it.

Feduccia's attempted main point is an exercise in what Makovicky and Dyke (2001) described as naive falsification over twenty years ago - taking some feature shared by birds and dinosaurs and claiming it's not homologous in those groups, and via a mysterious step 2 concluding phylogeny is in shambles and birds must be non-dinosaurian.  Feduccia's (2023) character de jure is the open acetabulum, classic dinosaurian character still seen in birds, and we can use Silesaurus to demonstrate Makovicky and Dyke's entire point that makes Feduccia's argument invalid and useless even if he was correct about the anatomy.

Traditionally an open acetabulum supports dinosaurian monophyly, but I'm a fan of the recent idea that silesaurs are a basal grade of ornithischian and it turns out dun dun DUN silesaurs have closed acetabula.  Thus genasaurs and saurischians most parsimoniously evolved open acetabula convergently.  According to Feduccia's logic, there goes the idea that ornithischians are closely related to saurischians and archosaurian phylogeny must be reevaulated.  But actually no, the vast majority of evidence still strongly supports ornithischians being closer to saurischians than pterosaurs, aphanosaurs, suchians, phytosaurs, etc. because it's not like this example of convergence magically creates evidence ornithischians are related to something else.  That would be naive falsification.

Top- Figure 3a of Feduccia (2023) illustrating (left to right) Stegosaurus, Allosaurus and 'Postosuchus'. Bottom- actual Postosuchus pelvis after Weinbaum (2002).

So anyway, did you know "Late Triassic “rauisuchians” like Postosuchus exhibit an entirely theropodan pelvic anatomy, except for the acetabulum, which is largely closed."?  Because I didn't.  The first thing that's funny is that Feduccia's figure of Postosuchus' pelvis (Fig. 3a) is copied from Figure 15 of Chatterjee's 1985 original description of the genus, and we've known at least since Long and Murry 1995 (TWENTY-EIGHT YEARS AGO) that it's a chimaera using the ilium of Lythrosuchus and the pubis of Shuvosaurus.  It's details like this that demonstrate how Feduccia et al. are stuck in the past.  In any case, Postosuchus has some very non-theropodish pelvic features like the low ilium, huge supracetabular buttress, only two sacral attachments, non-contacting pubis and ischium, absent obturator flange and the characteristic 'rauisuchian' medioventral tilt, but Feduccia doesn't know this because he's stuck in Chatterjee's 1980s world where Postosuchus might as well be a tyrannosaur ancestor.

Right away we get "An open acetabulum is considered one of the most unchallengeable synapomorphies of dinosaurs and birds as opposed to stem dinosauromorphs and dinosauriforms that had not yet achieved fully upright posture and still exhibit a closed or partially closed acetabulum", but as shown by potentially ornithischian silesaurs, nope.  You can go all the way back to Ferigolo and Langer (2007) for the concept, recovered in phylogenetic analyses at least by 2016 by Cabreira et al. and more recently and explicitly argued by Müller and Garcia (2020).  The latter don't even mention the word "acetabulum" because modern phylogenetics has long since moved past "unchallengeable" key characteristics.

Figure 2 of Novas (1996).
 

Most of Feduccia's paper seems to be written in response to a straw man BAD (Birds Are Dinosaurs) scientist imagining "fully open acetabulum" is to be taken literally, having no medial enclosure at all, and don't you know it, that's often untrue in birds and other pennaraptorans.  In reality, an "open acetabulum" in Dinosauria is contrasted with having only a narrow slit as in Lagosuchus, Ornithosuchus or indeed as illustrated in Chatterjee's 'Postosuchus' chimaera.  Just look at Figure 2 of Novas' classic 1996 work on dinosaur monophyly which shows the dinosaurian perforate acetabulum represented by Herrerasaurus with medial enclosure around the edges just as Feduccia illustrates in so many birds.  Even Feduccia's own figure of Stegosaurus' pelvis (which like his Allosaurus pelvis is ultimately copied from Marsh's papers from the 1800s- such a contemporary reference!) meant to show the "open acetabulum in dinosaurs" has a significant medial rim.  

Meleagris pelvis (top) as redrawn in Baumel and Witmer (1993) from (middle) Harvey et al. (1968), and (bottom) different specimen from Butendiek (1980).

Amusingly, Feduccia says "The Nomina Anatomica Avium, like most modern avian anatomical references, portrays Gallus (domestic chicken) and Anas (domestic duck) with fully open, dinosaurian acetabula, unlike older images (Figure 1), which show substantial medial acetabular walls."  His Figure 1 has drawings of "Gallus, Encyclopaedia Brittanica, 1911; Anas, The Vertebrate Skeleton, Cambridge Press, 1897", which in addition to being downright archaic, are a pop encyclopedia and general vertebrate anatomy book, neither of which seem like somewhere to trust little anatomical details from.  Also, the Nomina Anatomica Avium doesn't even figure the pelvis of Gallus or Anas, it has Meleagris (Figure 4.15).  And that is credited as being redrawn from Harvey et al.'s (1968) Meleagris osteology, which indeed shows a larger acetabular foramen than Feduccia's 1911 Gallus or 1897 Anas.  But maybe it's a fluke.  Let's check Butendieck's 1980 Meleagris osteology and nope, the foramen is even larger there.  Guess it's not a modern cladist conspiracy.

Feduccia insists on staying behind the times when he writes "The continued illogical application of “phylogenetic nomenclature” [70], “phylonyms” [9], and the arbitrary redefinition of established taxon names necessitates the following nomenclatural clarifications. ... “Archosauria” is also used sensu traditum [71,72] and is therefore equivalent to the Archosauriformes of Nesbitt [73], Ezcurra [74], and de Queiroz et al. [9]" and every other work dealing with archosaur phylogeny and nomenclature since the 90s!  Oh, except Benton's (1999) Scleromochlus redescription he cites as reference 72, which proposed the name Avesuchia for the crown group which nobody ever used again.  Why Feduccia insists on using a concept outdated by thirty-some odd years and expects to be taken seriously is a mystery.  Oh, and in his Table 1 Feduccia defines Ornithurae as "All those birds are more closely related to extant birds (Neornithes) than they are to Enantiornithes", so look who's applying phylogenetic nomenclature now.  Guess it can be logical as a concept, who would have guessed?

Top left- unfused Meleagris pelvis showing iliac contribution to the acetabulum (25) is larger than ischial contribution (64) (after Butendieck, 1980). Top right- Sinornis pelvis showing antritrochanter (vant) almost entirely on the ilium (after Sereno et al., 2002).  Bottom- Buitreraptor (left) and Berlin Archaeopteryx (right) showing antitrochanters (at) (after Agnolin and Novas, 2011).

It's not just acetabular closure that Feduccia is examining, he also comments on the distribution of supracetabular crests and antitrochanters.  For the latter, he notes "A structure homologized with the avian antitrochanter has been reported in ... a miscellany of coelurosaurs [16,102,103]. There is no osteological evidence that these structures are homologous: the avian antitrochanter forms primarily
[69] or almost exclusively [90] from the ischium, whereas the so-called “antitrochanters” of these nonavian taxa are almost exclusively iliac in composition ... Moreover, while continuity of function is not a requirement of homology, it should be noted that putative “antitrochanters” of so great a range of taxa cannot possibly have performed the specialized mechanical role that the true antitrochanter does in extant birds as part of their peculiar hindlimb locomotory system [90,104]."  So the antitrochanters of coelurosaurs aren't actually antitrochanters because they're on the ilium!  But wait, let's pull out Butendieck's turkey osteology again, and oh no!  Meleagris has an antitrochanter mostly formed by the ilium!  And while Feduccia says "In both enantiornithines and ornithurines, the maintenance of balance in obligately bipedal locomotion is linked to the presence of an antitrochanter", Sereno et al. (2002; in a figure Feduccia specifically cites) shows that in the enantiornithine Sinornis the antitrochanter is almost entirely on the ilium despite supposedly having the same function as in living birds!  That's also true in the Lecho Formation enantiornithine pelvis PVL 4042 by the way (Walker and Dyke, 2010: Fig. 14).  Given even those three examples, when Feduccia says "The putative “antitrochanters” of alvarezsaurs and therizinosauroids are iliac in composition", or that in Rahonavis "the purported antitrochanter, however, is iliac in origin", it lacks any force of argument whatsoever.  Since it CAN be that way in birds and even supposedly have the same function, it can also be that way in bird ancestors and relatives.

Similarly, for Archaeopteryx Feduccia claims "Agnolin and Novas [115] (Figure 3B) interpreted a slight swelling on the posteroventral rim of the acetabulum in the Berlin specimen as an antitrochanter, but this interpretation seems incorrect because (1) it is positioned on the posteroventral rim of the acetabulum, whereas the avian antitrochanter is posterodorsal to the acetabulum [69,90,104]; it is composed solely of the ilium, whereas the avian antitrochanter is composed exclusively or principally from the ischium."  But as the ischial peduncle doesn't wrap beneath the acetabulum, the structure is clearly on the posterodorsal rim, and is furthermore basically identical in structure and position to that of Sinornis (and Buitreraptor shown next to it, contra Feduccia's claim unenlagiids lack antitrochanters) except for being a bit more slender than in Sinornis.  How Feduccia can have looked at these figures and think Sinornis has an antitrochanter but Archaeopteryx does not is beyond me.  Another example of Feduccia's confusion is when he states "Avimimus portensosus [sic], however, possesses an ischial antitrochanter that, therefore, appears homologous with that in birds" but then notes A. nemegtensis was diagnosed in part by Funston et al. (2018) as lacking an antitrochanter.  Yet Funston et al.'s same figure cited by Feduccia shows the antitrochanter in A. portentosus is largely on the ilium (as Figure 4G doesn't even show the ischium) and indeed, A. nemegtensis doesn't preserve a proximal ischium at all so if the antitrochanter were ischial neither Funston et al. nor Feduccia would even know it lacked one!  The basic conclusion is Feduccia doesn't know what he's looking at, making his attempted review of antitrochanter distribution useless.

Feduccia is no better when discussing supracetabular crests, as evidenced when he says "Although Paul (2002) claims that a supracetabular crest is present in archaeopterygids, it is absent in the London, Berlin, Eichstatt and Munich specimens (Figure 8d)."  But Paul's Plate 24Ab clearly shows a convex outer rim in ventral view that defines a supracetabular crest in a photo of a cast of the London specimen, whereas Feduccia's Figure 8d is a horizontally oblique drawing of a reconstructed generic Archaeopteryx pelvis that couldn't show lateral convexity in dorsal/ventral view even if it was there.  So far from countering Paul, the medium is inferior, the subject is inferior, and the perspective would make evaluation impossible in any case.  Indeed, Paul's entire Plate 24 is an effective argument against everything Feduccia claims about antitrochanters and supracetabular crests, showing for example that tyrannosaurids lack a supracetabular crest, so apparently it wasn't integral to a functioning theropod gait, and that young Meleagris lacks an ossified antitrochanter, so maybe at least some of these theropods with seemingly small or absent antitrochanters had larger cartilaginous structures that enabled them to be functionally similar to living birds and/or Avimimus portentosus.

Right- Feduccia's (2023) Figure 5 (caption below). Top left- Megapnosaurus rhodesiensis pelvis (after Raath, 1977- see, I can cite old papers too!). Bottom left- Oksoko pelvis (flipped horizontally, after Funston et al., 2020).

My favorite part of this paper though is Figure 5, which shows drawings of the "Pelvis of the basal theropod Coelophysis (a) compared to an array of primarily ground-dwelling birds: (b) Solitary Tinamou (Tinamus solitarius), (c) Wild Turkey (Meleagris gallopavo), (d) Japanese Quail (Coturnix japonica), (e) Greater Roadrunner (Geococcyx californianus), (f) Emu (Dromaius novaehollandiae), (g) Bush Moa (Anomalopteryx didiformis), and (h) Elephant Bird (Aepyornis hildebrandti)."  The first thing of note is that the Coelophysis drawing is highly inaccurate, being a copy of Colbert's (1989) illustrations by Lois Darling, which "do not depict the anatomy of Coelophysis accurately" (Downs, 2000).  There are no pubic or obturator foramina, no obturator plate on the ischium, the supracetabular crest is not confluent with the ventral postacetabular edge, and rather importantly for this paper's subject the ilium is lacking the medial wall on the dorsal part of the acetabulam (that is partially ovelapped laterally by the supracetabular crest) and the large antitrochanteric surface formed by the ischial peduncle and ischium.  While I agree with Feduccia the latter structure is not homologous to the maniraptoran antitrochanter (which is on the outside rim of the acetabulum), it does combine with the dorsal section to make a significant surface medial to the acetabular rim.  Again, Feduccia is using a 30+ year old source that is well known to be wrong.

And what's even the point of the figure?  "Note the contrast between the condition in these cursorial birds, which presumably should most closely approach the putatively ancestral theropod condition with respect to their acetabular morphology, and the condition in Coelophysis."  First of all, why should an avian/neornithine anatomy that evolved in the Late Cretaceous converge with or regress to a Triassic group's morphology?  Second, modern birds have a functionally different gait from non-maniraptoriform theropods like coelophysoids at least, where the femur is more horizontal and less mobile, so even in terrestrial birds I don't see why any special acetabular anatomy would be similar.  Third, Feduccia thinks oviraptorosaurs are birds (e.g. Feduccia and Czerkas' 2015 "Testing the neoflightless hypothesis: propatagium reveals flying ancestry of oviraptorosaurs") and oviraptorids like Oksoko happened to have an even more open acetabulum than Darling's fake Coelophysis and a pelvis much more superficially similar to coelophysoids than to modern birds.  So according to Feduccia, some cursorial birds DID approach what he imagined the ancestral theropod condition to be like.  He just chose to only figure cursorial crown birds, which aren't very similar to coelophysoids in pelvic structure.

Looks like my work in the Lori description (Feduccia's reference 52) got cited! "Reliance on simple tabulations of step count difference between constrained and unconstrained trees [52] to determine whether the most basal members of pennaraptoran clades have been correctly resolved by parsimony analysis of current data matrices is naive and takes no account of the statistical significance of differences in tree populations [50]."  Oh noes!  I was naive!  And what's this reference 50 I should have taken into account?  James and Pourtless 2009!  The study that actually found birds as maniraptorans, coelurosaurs, theropods and dinosaurs, but which hid it by only figuring majority rule bootstrap trees and always pruned out Effigia because it falling out as an ornithomimosaur was too embarrassing of a result even for them!  And that was even after scoring all dinosaur manual characters as unknown, even in the pentadactyl Eoraptor and Herrerasaurus with zero controversy of digital homology!  Bwa ha ha!  Yeah, those are some methodologies I really should have taken to heart.  Hey, at least Feduccia cited me as the correct author this time!

Top- Ornitholestes holotype ilium and proximal pubis (after AMNH's 2007 digital collections). Middle- Allosaurus USNM 4734 ilium (after Gilmore, 1920). Bottom- Tyrannosaurus FMNH PR2081 ilium and sacrum (after Brochu, 2003).  Note even the latter classic theropod has significant medial walls on the peduncles.

But what does any of this have to do with birds not being dinosaurs?  Feduccia spends lots of time discussing the amount of acetabular closure in modern birds, always emphasizing the medially walled areas, and going so far as to say "it is more difficult to adequately assess acetabular morphology in extant birds than is generally realized. Preparatory methods used to produce skeletal collections in museums (e.g., defleshing with dermestid beetles, oxidation methods involving HO, and ammonia, chemical bleach, and maceration) can damage or destroy fragile anatomical features" so that we can't even trust our own specimens!  It's as if in his typological mind, this is making birds "less dinosaurian" because dinosaurs are things with open acetabula, and shouldn't this be concerning to us BADists?!  No.  No it should not.  Hell, all crown birds could have fully closed acetabula like derived ankylosaurs and it wouldn't matter one bit because key characters aren't a thing and evolution happens.  Just like it doesn't make ankylosaurs any less dinosaurian.  We wouldn't even need the fact that every single stem bird fossil* has an open acetabulum regardless of preservation, and that makes it undeniable that regardless of the condition in crown birds, and regardless of what birds evolved from, Mesozoic birds have open acetabula.

* Even scansoriopterygids which he lies about, claiming "they have closed acetabula" when even his previous description with Czerkas (2014) cited "the partially open acetabulum in Scansoriopteryx."  Czerkas and Yuan's (2002) original description also states "the indication from the texture and color extending from the ilium suggests that the hip socket was not as widely perforated as in theropods or dinosaurs in general. The inner edge of this reduced perforation in the hip socket can be seen in both acetabula on the counterslab."

Feduccia will emphasize "partially closed" in many examples, but non-pennaraptoran theropods are not the monolith he takes them for when as in 2014 he and Czerkas write "theropod dinosaurs, invariably exhibiting a completely perforated and open acetabulum", or as he says in the present paper "The condition in the large Jurassic tetanurine Allosaurus (Figure 3) may be taken as stereotypical of its development in Theropoda", with Figure 3 being redrawn from the 1880s.  Just check out classic theropod Ornitholestes above with a medial wall taking up almost half of the acetabular circle.  Even in Allosaurus itself, if you look at an actual photo you can see that Figure 3's seemingly uninturrupted dorsal edge is wrongly drawn and that half the ischial peduncle is medial as is some of the pubic peduncle but most of that is hidden by the laterally overlapping supracetabular crest except for the posteroventral corner.  Dinosaurs all over the cladogram were changing the amount of medial acetabular ossification and birds were no exception.

And really, the takeaway I got from Feduccia's data is that just like most characters, the development of acetabular closure, supracetabular crest extent and antitrochanter size are labile and prone to homoplasy.  They are not integral parts of a locomotory system, and similar taxa can manage movement just fine when these variables are changed.  That's why you can have Avimimus portentosus and A. nemegtensis with such drastic differences in antitrochanter development, which Feduccia seems baffled by- "it is not clear why a single genus should be polymorphic for this character state, it is difficult to interpret this character conflict."  Similarly Feduccia says "It is surprising, given the
frequent characterization of birds as having — like dinosaurs — completely open acetabula to
discover that rotisserie [chicken] specimens have partially closed acetabula with a perforation covered
by soft tissue."  Are we assuming Mesozoic dinosaur acetabular foramina were not covered by soft tissue?  And is there really a functional difference between the paper thin medial bone walls Feduccia is worried might be present in modern birds but destroyed by preparation and a fibrocartilage wall hypothetically present in a theropod with an open bony acetabulum?  Based on Feduccia's described variation within modern birds, I'm doubtful.  But he's so obsessed with these being typologically enforced key characters essential to function and evolutionary history, for both himself and his BAD straw man, that them being not all that important in anathema to him.

Now, this is out of order but I wanted another figure to liven up the post.  On the left is "Late Jurassic Archaeopteryx (image composites of varied sizes, primarily after P. Wellnhofer, based primarily on the Munich specimen, with details from the London, Berlin, and Eichstitt specimens;".  Yeah, there is no closing parenthesis and I think "image composites of varied sizes" refers to the Gansus, Qiliania and Pterygornis pictures featured elsewhere in this figure.  More importantly as noted far above, this figure is just a drawing (by K. Grow apparently) of a hypothetical composite, and while it is used as an argument against a supracetabular crest in the genus it is incapable of showing the development of a supracetabular crest directed at the viewer as in e.g. Ornitholestes.  On the right is an item labeled "Microraptor, the Early Cretaceous four-winged bird-like glider (dromaeosaur), considered by many an early bird. (Microraptor photo courtesy D. Burnham)", but some digging finds this is actually the structure labeled "Right lateral view of microraptoran pelvis (modified cast)" in Burnham's (2007) thesis.  The latter claims it is "based on a recent transfer preparation of a Chinese microraptorine, which exposes a lateral view of the acetabulum."  Who knows what parts were modified and we have no traceable specimen to confirm anything with, although the preacetabular process and ischial tip don't look like those in actual Microraptor fossils.  I'm not even implying any purposeful anatomical inaccuracy, just noting that Feduccia passed off a "modified cast" as an apparently real specimen.

In the end, Feduccia admits that if "the first birds — and at least taxa like the microraptorines — were not terrestrial cursorial bipeds, like theropods, but trunk-climbing gliders" it "would be consistent with arguments that (at least some of) these taxa are “neoflightless” theropods, whose immediate ancestors underwent transformations in the theropod locomotory system (perhaps because of a shift to arboreality)."  But he rejects this, in part due to "the discovery of a “tetrapteryx” stage in early aviation evolution", which is a Petersian thing to say because not even the relatively well resolved pennaraptoran consensus phylogeny views the tetrapteryx stage as an established thing, let alone Feduccia's wacky world of uncertainty where who knows how oviraptorosaurs, troodontids, eudromaeosaurs, microraptorians, unenlagiids, anchiornithines and archaeopterygids interrelate.  Sure microraptorians have big leg wings, and Sapeornis and anchiornithines have a much shorter version, but the former are dromaeosaurids and the latter are maybe archaeopterygids, maybe avialans, maybe troodontids.  The structures are lacking in Caudipteryx, troodontids, Archaeopteryx and pygostylians, so in order for a tetrapteryx stage to exist, dromaeosaurids and/or anchiornithines would have to be ancestral to crown birds somewhere or we have a lot of reversals.  Note Feduccia claims "if Jinfengopteryx is, in fact, a basal troodontid [140,236] (but see discussions in [115,139,162]) then troodontids also primitively exhibited a “tetrapteryx” bauplan", but Jinfengopteryx has no long leg feathers at all, not even long tibiotarsal ones like Archaeopteryx and basal pygostylians.  So that's just him being wrong again.

And in part the rejection is due to... it's really not made clear.  Feduccia assumes us BADists are as constrained by imagined evolutionary just-so stories as he is, claiming we are bound to "the argument — advanced since Huxley, championed by Ostrom, repeated ad infinitum — that the obvious reason birds are obligate bipeds and that they never passed through an evolutionary phase in which all four limbs were integrated into the flight mechanism, is that birds are descended from obligate bipeds, viz. theropods."  But he already said a facultatively bipedal stage (around the paravian stem maybe?) due to arboreal habits would still be consistent with a theropod ancestry, as quoted in the prior paragraph.  Feduccia continues "These data instead suggest that the reason bipedalism in birds differs fundamentally from bipedalism in all other archosaurs [does it?] ... is that birds started their evolutionary trajectory toward obligate bipedalism from a different starting point than the system employed to such success by dinosaurs."  But poposaurs and dinosaurs (or alternatively saurischians and Lesothosaurus+genasaurs) started their obligate bipedalism trajectory via facultative bipeds with a more sprawling stance, more closed acetabula, no antitrochanter and less inturned femoral heads just as Feduccia believes birds did.  It's just special pleading to claim they are "fundamentally different."  Finally, he claims "This is a logical explanation for the surprising persistence of medial occlusion of the acetabulum in many pennaraptorans and the absence, in most, of either well-defined supracetabular crests or antitrochanters."  This despite explicitly saying two pages ago "Oviraptorosaurs uniformly display fully perforate acetabula" and "Troodontids have fully perforated acetabula", so by "many pennaraptorans" Feduccia really just means dromaeosaurids.  He also said on the previous page "Compsognathids are “prototypical” small theropods [221], yet they lack a supracetabular crest or antitrochanter", so why would this be surprising in most pennaraptorans?  (lacking a hypertrophied antitrochanter like ornithurines at least...)

Amusingly enough, the most vehement objections to BAD are in Feduccia's Figure 7 caption showing hesperornithid pelves.  This claims without supporting data "the acetabula show that they are definitively not allied with dinosaurs" and "Hesperornithiforms are often termed diving dinosaurs, but given their acetabula anatomy this designation is erroneous."  I'd think such late and specialized divers would be of little relevance, but what do I know...  Hey that long and low postacetabular process is looking pretty similar to Postosuchus.  Maybe we've found our archosaurian avian ancestor ;)

And that's it.  Feduccia's Conclusion is "The hypothesis that birds are maniraptoran theropod dinosaurs, despite the certitude with which it is proclaimed, continues to suffer from unaddressed difficulties [29-31,50,237]", with references 29-31 being his own books and paper, 50 we recall is James and Pourtless' terrible TERRIBLE attempt at a cladistic analysis, and 237 is James' fawning review of Feduccia's latest book.  Ha.  You know what's an unaddressed difficulty in Feduccia's hypothesis?  Thirty-plus years since he publically doubted the dinosaurian origin of birds, we still have pennaraptorans emerging from some mysterious lineage of Triassic archosaur(-iform)s.  And yet we've closed the gaps so well in theropod phylogeny that the precise relationships among basal avialans, basal paravians, basal pennaraptorans, basal maniraptorans/-iforms, basal neocoelurosaurs, basal coelurosaurs, etc. are controversial due to homoplasy.  Surely any day now we'll find the evolutionary intermediates between Middle Jurassic scansoriopterygids and Triassic ???????.  Anything But a Small Running Dinosaur indeed.

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