Sunday, July 9, 2023

New data on African abelisaurs

Hi everyone.  I'm a coauthor on a paper published this week reviewing the record of African abelisauroids (de Souza-Júnior et al., 2023).  I want to thank André Luis de Souza-Júnior for adding me, as he used The Theropod Database as a resource.  That's how you do it!  We incorporated my corrections and suggestions back in 2020 before it was submitted, but as is typical of these projects there have been new discoveries since.  Here are some additional records-

unnamed Abelisauroidea (Lasseron, 2020)
Early Bathonian, Middle Jurassic
GEA 6, Guelb el Ahmar, Anoual Formation, Morocco
Material
- (MNHN GEA6-5) lateral tooth (2.58x1.86x1.39 mm)
Early Bathonian, Middle Jurassic
GEA 7, Guelb el Ahmar, Anoual Formation, Morocco
(MNHN GEA7-14) lateral tooth (3.75x2.51x1.59 mm)
(MNHN GEA7-17) lateral tooth (2.60x2.06x1.09 mm)
Comments- Discovered in 2015 and/or 2018, Lasseron (2020) concluded "The convexity of the two carinae is a remarkable feature. It recalls the Abelisauridae (Smith, 2007; Hendrickx & Mateus, 2014), but also the Noasauridae (Carrano et al., 2002), an identification which would be consistent with the small size of these teeth. We therefore attribute these teeth to an Abelisauroidea gen. and sp. indet." (translated).
Reference- Lasseron, 2020. Paleobiodiversite, evolution et paleobiogeographie des vertebres mesozoiques africans et gondwaniens : apport des gisements du Maroc oriental. Doctoral thesis, Museum National D'Histoire Naturelle. 493 pp.

unnamed abelisauroid (Lasseron, 2020)
Berriasian, Early Cretaceous
KM-A1,
Ksar Metlili, Ksar Metlili Formation, Morocco
Material
- (FSAC-KM-A1-12) lateral tooth (3.41x2.26x1.47 mm)
Comments- Collected in 2010, 2015 or 2018, Lasseron (2020) concluded "The convexity of the two carinae is a remarkable feature. It recalls the Abelisauridae (Smith, 2007; Hendrickx & Mateus, 2014), but also the Noasauridae (Carrano et al., 2002), an identification which would be consistent with the small size of these teeth. We therefore attribute these teeth to an Abelisauroidea gen. and sp. indet." (translated).
Reference-
Lasseron, 2020. Paleobiodiversite, evolution et paleobiogeographie des vertebres mesozoiques africans et gondwaniens : apport des gisements du Maroc oriental. Doctoral thesis, Museum National D'Histoire Naturelle. 493 pp.

undescribed possible abelisauroid (Smith, Lamanna, Dodson, Attia and Lacovara, 2001)
Cenomanian, Late Cretaceous
Bahariya Oasis, Baharija Formation, Egypt

Material- teeth (FABL 7.5 mm)
Comments- These "recently recovered" teeth are stated to have significantly more serrations per mm than similarly sized Deinonychus or Dromaeosaurus and have "denticle morphologies and the average crown base width (CBW) and CBL9crown base length] relationships ... more reminiscant of abelisaurids than dromaeosaurids."
Reference- Smith, Lamanna, Dodson, Attia and Lacovara, 2001. Evidence of a new theropod from the Late Cretaceous of Egypt. Journal of Vertebrate Paleontology. 21(3), 102A.

Kem Kem noasaurid cervical FSAC-KK-5016 in (A) right lateral, (B) left lateral, (C) anterior, (D) dorsal, (E) ventral and (F) posterior views (after Smyth et al., 2020). Scale = 10 mm.

unnamed Noasauridae (Russell, 1996)
Cenomanian, Late Cretaceous
Kem Kem beds, Morocco

Material- (CMN 41873; bone taxon H) distal humerus (48 mm wide) (Russell, 1996)
(FSAC-KK-5016) (~1.5 m) incomplete ~fourth cervical vertebra (21 mm) (Smyth, Ibrahim, Kao and Martill, 2020)
Comments- The humerus is very similar to Masiakasaurus.
References- Russell, 1996. Isolated dinosaur bones from the Middle Cretaceous of the Tafilalt, Morocco. Bulletin du Museum national d'Histoire naturelle. 18, 349-402.
Smyth, Ibrahim, Kao and Martill, 2020 (online 2019). Abelisauroid cervical vertebrae from the Cretaceous Kem Kem beds of southern Morocco and a review of Kem Kem abelisauroids. Cretaceous Research. 108, 104330.

Kem Kem abelisaurid axis FSAC-KK-5015 in (A) right lateral, (B) left lateral, (C) anterior, (D) dorsal, (E) ventral and (F) posterior views (after Smyth et al., 2020). Pink area is filler. Scale = 20 mm.

unnamed Abelisauridae (Fanti, Cau, Martinelli and Contessi, 2014)
Cenomanian, Late Cretaceous
Kem Kem beds, Morocco
Material
- (CMN 50446) tooth (~24x~11x? mm) (Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020)
?(FSAC-KK 912) tooth (~17x~10x? mm) (Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020)
?(FSAC-KK 913) tooth (~22x~12x? mm) (Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020)
?(FSAC-KK 914) partial tooth (Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020)
?(FSAC-KK 915) tooth (~18x~8x? mm) (Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020)
(FSAC-KK-5015) (~2.7 m) axis (38 mm) (Smyth, Ibrahim, Kao and Martill, 2020)
?(FSAC-KK unnumbered) tooth (~16x~11x? mm) (Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020)
(MNHN MRS 348) tooth (48x17x13 mm) (Fanti, Cau, Martinelli and Contessi, 2014)
(MNHN MRS 783) tooth (28x14x6 mm) (Fanti, Cau, Martinelli and Contessi, 2014)
(MNHN MRS 1266) tooth (34x14x7 mm) (Fanti, Cau, Martinelli and Contessi, 2014)
(MNHN MRS 1838) tooth (36x19x9 mm) (Fanti, Cau, Martinelli and Contessi, 2014)
(MSNM V6053) tooth (~23x~10x? mm) (Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020)
Comments- Fanti et al. (2014) list measurements of four "Abelisauridae indet." teeth housed in the MNHN which have MRS numbers corresponding to the Gara Sbaa locality (e.g. Rebbachisaurus type) of the Kem Kem beds.  Smyth et al. suggested the axis FSAC-KK-5015 represents an abelisaurid outside Majungasaurinae+Brachyrostra, perhaps a juvenile Rugops.  Ibrahim et al. (2020) figure CMN 50446 and MSNM V6053 as "?Abelisaurid tooth", and several others as "Indeterminate theropod teeth" which seem to be abelisaurid based on the low distal curvature in each, and marginal undulations in FSAC-KK 912 and 915.
References- Fanti, Cau, Martinelli and Contessi, 2014. Integrating palaeoecology and morphology in theropod diversity estimation: A case from the Aptian-Albian of Tunisia. Palaeogeography, Palaeoclimatology, Palaeoecology. 410, 39-57.
Ibrahim, Sereno, Varricchio, Martill, Dutheil, Unwin, Baidder, Larsson, Zouhri and Kaoukaya, 2020. Geology and paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco. ZooKeys. 928, 1-216.
Smyth, Ibrahim, Kao and Martill, 2020 (online 2019). Abelisauroid cervical vertebrae from the Cretaceous Kem Kem beds of southern Morocco and a review of Kem Kem abelisauroids. Cretaceous Research. 108, 104330.

Quseir abelisaurid left fibula in (F) lateral, (G, H) medial and (I, J) proximal views (after Salem et al., 2021). Scale = 20 mm.

unnamed probable abelisaurid (Sallam, O'Connor, Kora, Sertich, Seiffert, Faris, Ouda, El-Dawoudi, Saber and El-Sayed, 2016)
Middle Campanian, Late Cretaceous
Baris, El Hindaw Member, Quseir Formation, Kharga Oasis, Egypt
Material- (MUVP 187) proximal fibula (25x5 mm prox)
Comments- Discovered in 2008 or 2010, Sallam et al. (2016) initially reported "A proximal left fibula of a theropod dinosaur was also collected from the Baris area" and listed it as Theropoda indet..  Salem et al. (2021) noted the prominent m. iliofibularis tubercle is like abelisaurids and it has a "wide, slightly deep [proximomedial] fossa that closely resembles the condition in the abelisaurid Majungasaurus."  They say it "exhibits some affinities with abelisaurids" and refer to it as "Cf. Abelisaurid" in theit table 3. 
References- Sallam, O'Connor, Kora, Sertich, Seiffert, Faris, Ouda, El-Dawoudi, Saber and El-Sayed, 2016. Vertebrate paleontological exploration of the Upper Cretaceous succession in the Dakhla and Kharga Oases, Western Desert, Egypt. Journal of African Earth Sciences. 117, 223-234.
Salem, O'Connor, Gorscak, El-Sayed, Sertich, Seiffert and Sallam, 2021. Dinosaur remains from the Upper Cretaceous (Campanian) of the Western Desert, Egypt. Cretaceous Research. 123, 104783.

Elrhaz abelisaurid carina MNHN F.GDF-M30 in (E) labiolingual and (F) mesiodistal views (after Pochat-Cottilloux et al., 2022). Scale = 1 mm.

unnamed Abelisauridae (Pochat-Cottilloux, Allain and Lasseron, 2022)
Aptian, Early Cretaceous
GAD 5, Gadoufaoua, Elrhaz Formation, Niger
Material- (MNHN F.GDF-M30) two tooth fragments
(MNHN F.GDF-M37) two partial teeth
Comments- Collected in 1970, Pochat-Cottilloux et al. (2022) noted "some of this material was stored at the MNHN in a separate box" and had a "lighter color and a better quality of fossil preservation than other seen in other samples" which "suggested a different depositional environment to that of other samples so, as a result, this sample was separated from the rest" ... "as "site GADb"."  This is true for MNHN F.GDF-M30.  The authors state there are 3 serrations per mm on MNHN F.GDF-M30 and 4 per mm on MNHN F.GDF-M37, in the latter the carinae "extend along the entire length of both sides of the base" and in all specimens "the shape of the denticles and their number are typical of theropod teeth and could be assignable to Abelisauridae."
Reference- Pochat-Cottilloux, Allain and Lasseron, 2022. Microvertebrate fauna from Gadoufaoua (Niger, Aptian, Early Cretaceous). Comptes Rendus Palevol. 21(41), 901-926.

Galula abelisaurid tooth TNM 02088 in labial view (after O'Connor et al., 2006). Scale = 5 mm.

unnamed Abelisauridae (O'Connor, Gottfried, Stevens, Roberts, Ngasala, Kapilima and Chami, 2006)
Albian, Early Cretaceous
TZ-07, Namba Member of the Galula Formation, Tanzania

Material- (TNM 02088) lateral tooth (~19x~11.5x? mm)
(TNM coll.) eight lateral teeth, two anterior teeth
Comments- Discovered between 2002 and 2005, this material was described as theropod by O'Connor et al. (2006) and referred to the Unit I of the Red Sandstone Group at the time.  Roberts et al. (2010) subsequently revised the stratigraphic nomenclature, naming Unit I the Galula Formation.  Salem et al. (2021) refers the isolated teeth to Abelisauridae without comment, which seems likely given their stratigraphy, locality, size and morphology (particularly the nearly straight distal edge).  Several of the teeth were associated with the holotype of the titanosaur Shingopana, "suggesting a possible scavenging event."  Note the theropod caudals from the same locality described by O'Connor et al. differ from abelisaurids in their strong infradiapophyseal laminae and are here tentatively referred to Megaraptora.
Teeth have ~13-16 serrations per 5 mm mesially and distally.  O'Connor et al. further indicate "Two teeth are D-shaped in cross-section, indicating a position in the rostralmost portion of either the dentary or premaxilla."
References- O'Connor, Gottfried, Stevens, Roberts, Ngasala, Kapilima and Chami, 2006. A new vertebrate fauna from the Cretaceous Red Sandstone Group, Rukwa Rift Basin, southwestern Tanzania. Journal of African Earth Sciences. 44, 277-288.
Roberts, O'Connor, Stevens, Gottfried, Jinnah, Ngasala, Choh and Armstrong, 2010 (online 2009). Sedimentology and depositional environments of the Red Sandstone Group, Rukwa Rift Basin, southwestern Tanzania: New insight into Cretaceous and Paleogene terrestrial ecosystems and tectonics in sub-equatorial Africa. Journal of African Earth Sciences. 57, 179-212.
Salem, O'Connor, Gorscak, El-Sayed, Sertich, Seiffert and Sallam, 2021. Dinosaur remains from the Upper Cretaceous (Campanian) of the Western Desert, Egypt. Cretaceous Research. 123, 104783.

Gokwe abelisaurid (left, right) and averostran (center) teeth (University of Zimbabwe coll.) (after Bond and Bromley, 1970).

undescribed Abelisauridae (Bond and Bromley, 1970)
Early Cretaceous
Gokwe Formation, Zimbabwe
Material
- (University of Zimbabwe coll.) at least two teeth (~48x~31x?, ~49x~34x? mm)
Comments- Bond and Bromley (1970) were the first to figure three theropod teeth, discovered between 1962 and 1970, as their Plate 1A "Reptilian teeth of two types from the Gokwe Formation." Listed as being " in collection of Geology Department, University College of Rhodesia", the latter has since been renamed the University of Zimbabwe.  The first and third are clearly abelisaurid, with broad bases, straight to convex distal edges and fine serrations both mesially and distally (~6 per 5 mm on both carinae).  The second is narrower and more recurved, so referred to Averostra indet. here.
Reference- Bond and Bromley, 1970. Sediments with the remains of dinosaurs near Gokwe, Rhodesia. Palaeogeography, Palaeoclimatology, Palaeoecology. 8(4), 313-327.

Baharija abelisaurid tenth cervical vertebra MUVP 477 in (a) anterior, (b) posterior, (c) left lateral, (d) right lateral), (e) ventral and (f) dorsal views (after Salem et al., 2021).


unnamed possible brachyrostran (Salem, Lamanna, O'Connor, El-Qot, Shaker, Thabet, El-Sayed and Sallam, 2021)
Early Cenomanian, Late Cretaceous
Gebel el Dist, Baharija Formation, Egypt
Material
- (MUVP 477) (~5.8 m) tenth cervical vertebra (67.00 mm)
Comments- Discovered in 2016, Salem et al. (2021) added this to Tortosa et al.'s ceratosaur matrix and recovered it as an abelisaurid based on "(1) long axis of diapophysis forms angle of 65° to midsagittal plane; (2) dorsal surface of neural arch clearly delimited from lateral surface of diapophysis; (3) deep spinoprezygapophyseal and spinopostzygapophyseal fossae; and (4) well-developed epipophyses, comparable to those observed in the tenth cervicals of Majungasaurus and MPM 99 (but smaller than those of Carnotaurus and Ekrixinatosaurus novasi)."  The resulting Salem et al. (2022) publication officially describing the specimen did not use character 1.  While it was a brachyrostran (in a polytomy with Ekrixinatosaurus, Ilokelesia and the derived clade) in majority rule trees, a posteriori pruning of taxa was not done to determine if this is real signal or merely an artifact.  Examination of the 2022 supplementary data should resolve this.
References- Salem, Lamanna, O'Connor, El-Qot, Shaker, Thabet, El-Sayed and Sallam, 2021. First definitive record of Abelisauridae from the Bahariya Formation, Bahariya Oasis, Western Desert of Egypt increases diversity of large-bodied theropods in the MIddle Cretaceous of northeastern Africa. The Society of Vertebrate Paleontology Virtual Meeting Conference Program, 81st Annual Meeting. 225-226.
Salem, Lamanna, O'Connor, El-Qot, Shaker, Thabet, El-Sayed and Sallam, 2022. First definitive record of Abelisauridae (Theropoda: Ceratosauria) from the Cretaceous Bahariya Formation, Bahariya Oasis, Western Desert of Egypt. Royal Society Open Science. 9: 220106.



Additionally, a review paper isn't really the place for new information or unpublished sources, so here are some extensive updates to poorly documented finds-

"Sidormimus" Molina-Perez and Larramendi, 2019
= "Dogosaurus" Anonymous, 2000 online
Aptian-Albian, Early Cretaceous
Gadoufaoua, Elrhaz Formation, Niger

Material- (MNN GAD coll.) (~1 m) partial skeleton including maxilla, cervical ribs, dorsal vertebrae, dorsal ribs, uncinate processes, sacral vertebrae, scapula, coracoid, sternal plates, sternal ribs, humerus, radius, ulna, carpus, manus including manual digit II, phalanges, manual unguals and manual claw sheath, pelvis including pubis and hindlimb including femur, tibia, fibula, calcaneum, metatarsus, pedal digit II, pedal digit III, pedal digit IV and pedal unguals
Comments- This specimen was discovered on September 13 2000 and announced by Lyon (2000 online) as "a brand new, dog-sized theropod, which the team has affectionately (but unofficially) named "Sidormimus."" and a "new, dog-sized carnivore - perhaps one of the smallest dinosaurs ever", with a photo of the specimen in situ.  The same photo was labeled Dogosaurus on a dispatch from Project Exploration on the National Geographic website, which also stated it was "no more than three feet long. Its slender neck and ribcage were preserved poking out of the rock. Its long, clawed hind leg was uncovered as we dug around the exposed bones." Sereno et al. (2004) first announced the specimen in print, as "a small (1 m) articulated skeleton showing many abelisauroid and noasaurid synapomorphies, including pneumatized presacral and sacral neural arches, proportionately long presacral centra, and others" and "preserves a maxilla and pelvic girdle, the former of which bears the distinctive abelisaurid pit-and-groove texturing of the skull bones."  They include it in their cladogram as "Gadoufaoua noasaurid", but it is not an OTU in the matrix.  It is also listed in Sereno and Brusatte (2008) as "undescribed noasaurid" in a faunal list, and is noted to have a pubic boot more with limited expansion than the "Kryptops" postcrania MNN GAD1-2. Sidor (pers. comm. 2005) confirms the "Sidormimus" specimen is the Elrhaz noasaurid. Sereno (2010) devoted an SVP abstract to it, noting the specimen has- long and robust posterior cervical ribs, dorsal centra more than twice as long as tall, five uncinate processes (unique among non-maniraptoran theropods), posteriorly directed glenoid, enlarged coracoid, ossified sternal plates and ribs, forelimb 18% of hindlimb length, robust deltopectoral crest and olecranon process, manual digit II longer than III, straight manual unguals, tibia longer than femur, pedal digits II and IV much shorter than III, and short flat pedal unguals.  Sereno (2017) provided further information- straight tibia, weak iliofibularis tubercle on fibula, fibula distally fused with calcaneum, no dorsal vascular groove on pedal unguals.  The co-occuring Afromimus shared fibular-calcaneum fusion but differs in the other characters, in addition to having a more robust proximal fibula and distal fibula which is expanded transversely.  Molina-Perez and Larramendi (2019) first used the name in print, specified to be a nomen nudum.
References- Lyon, online 2000. http://web.archive.org/web/20121024124915/http://www.projectexploration.org/niger2000/9_15_2000.htm
Anonymous, online 2000.  http://web.archive.org/web/20001208070300/http://www.nationalgeographic.com/dinoquest/profile_01_dispatch2b.html
Sereno, Wilson and Conrad, 2004. New dinosaurs link southern landmasses in the Mid-Cretaceous. Proceedings of the Royal Society, Series B. 271, 1325-1330.
Sereno and Brusatte, 2008. Basal abelisaurid and carcharodontosaurid theropods from the Lower Cretaceous Elrhaz Formation of Niger. Acta Palaeontologica Polonica. 53(1), 15-46.
Keillor, Sereno and Masek, 2010. Range of movement in a noasaurid forelimb: In situ data and joint reconstruction. Journal of Vertebrate Paleontology. Program and Abstracts 2010, 114A.
Sereno, 2010. Noasaurid (Theropoda: Abelisauroidea) skeleton from Africa shows derived skeletal proportions and function. Journal of Vertebrate Paleontology. Program and Abstracts 2010, 162A.
Sereno, 2017. Early Cretaceous ornithomimosaurs (Dinosauria: Coelurosauria) from Africa. Ameghiniana. 54, 576-616.
Molina-Perez and Larramendi, 2019. Dinosaur Facts and Figures: The Theropods and Other Dinosauriformes. Princeton University Press. 288 pp.

"Titanovenator" Boyd, 2020 online
"T. kenyaensis" Boyd, 2020 online
Maastrichtian, Late Cretaceous
Lapurr sandstone (= Turkana Grits), Turkana, Kenya
Material
- (KNM-WT coll.) (~11-12 m) multiple specimens including cranial material (including a partial skull - premaxilla, postorbital and braincase), axial material and appendicular material (including astragalocalcaneum)
Comments- Discovered in 2004, this is based on unassociated material referred to one taxon "based on morphological consistency and on the recovery of specimens from a narrow stratigraphic and geographic area."  Abelisaurid characters listed by Sertich et al. (2013) include- "a tall, rugose premaxilla, an anteroventrally inclined posterior border of the postorbital," ... "a prominent dorsal projection of the parietals and supraoccipital" and an "ascending process [that] is low and subrectangular, separated from the anterior surface of the astragalus by a distinct fossa."  They further note the "skull is strongly coossified, with a thickened but weakly sculptured skull roof", "no prominent cranial ornamentation is evident" and "the astragalocalcaneum is completely coossified and displays a prominent transverse sulcus on the anteroventral surface."  The museum collection is based on an azhdarchid vertebra found by the same team from the same locality (O'Connor et al., 2011).
Boyd (2020) included the name Titanovenator kenyaensis in the pdf visual portion of her "Ask a Geologist" presentation for RUGM.  It accompanies a photo of the MCN Carnotaurus cast that is also labeled Abelisauridae gen. et sp. nov., and based on the name refers to Sertich et al.'s (2013) giant Kenyan abelisaurid taxon.  It is a nomen nudum as the pdf was not "issued for the purpose of providing a public and permanent scientific record" (ICZN Article 8.1.1) and doesn't "state the date of publication in the work itself" (Article 8.5.2), while the name itself was not "registered in the Official Register of Zoological Nomenclature (ZooBank)" (Article 8.5.3) or "accompanied by a description or definition that states in words characters that are purported to differentiate the taxon" (Article 13.1.1).  The name (as "Titanovenator kenyanis") actually predates Boyd's presentation, originating on a Jurassic Park message board from 2013 in a post under the pseudonym Rex Fan 684, but this is not considered a source for catalogued nomina nuda here.
References- Sertich, Manthi, Sampson, Loewen and Getty, 2006. Rift Valley dinosaurs: A new Late Cretaceous vertebrate fauna from Kenya. Journal of Vertebrate Paleontology. 26(3), 124A.
O'Connor, Sertich and Manthi, 2011. A pterodactyloid pterosaur from the Upper Cretaceous Lapurr sandstone, west Turkana, Kenya. Anais da Academia Brasileira de Ciências. 83(1), 309-315.
McCoy, 2013 online. http://www.jurassicworld3.net/topic/28609
Sertich, Seiffert and Manthi, 2013. A giant abelisaurid theropod from the Latest Cretaceous of northern Turkana, Kenya. Journal of Vertebrate Paleontology. Program and Abstracts 2013, 211.
Boyd, 2020 online. Ask a Geologist: Geology & Paleontology of Kenya. Rutgers Geology Museum. 25 pp.

Duwi abelisaurid teeth (MGUP coll.; lost) in (left) labiolingual and (right) basal view (after Gemmellaro, 1921).

unnamed Abelisauridae (Di Stefano, 1919)
Late Campanian, Late Cretaceous
Duwi Formation, Al Sharauna, Egypt

Material- (MGUP MEGA002; lost?) tooth (16.63x13.01x6.69 mm) (described by Smith and Lamanna, 2006)
Late Campanian, Late Cretaceous
Duwi Formation, Al Sharauna, Gebel Duwi and/or Gebel Nakheil, Egypt

(MGUP MEGA001) partial lateral tooth (?x~22.7x? mm) (Di Patti, pers. comm. 6-2023)
(MGUP MEGA002 B) lateral tooth (~35.2x~25x? mm) (Di Patti, pers. comm. 6-2023)
(MGUP MEGA003) partial lateral tooth (?x~30x? mm) (Di Patti, pers. comm. 6-2023)
(MGUP coll.; lost) more than two lateral teeth
Comments- Gemmellaro (1921) referred several remains to Megalosaurus crenatissimus, from three localities in eastern Egypt.  The phosphate layers of Gebel Duwi are the Late Campanian Duwi Formation (e.g. Salama et al., 2021).  Similarly, "Phosphate mines at Kosseir-el-Khadim, Gebel Nakheil, near Kosseir [now Quseer], on the Red Sea" are also the Duwi Formation (Valentine, 1985).  The third locality has been mistaken in every subsequent reference as "Sciarauna-el-Ghibli, presse Sibaiya (Valle del Nilo)", but the 'c' is actually a poorly photocopied 'e', as indicated by Di Stefano's (1919) original publication of the expedition which states "The richest and most extensive deposit is the one found on the hill of Seiarauna, on which are the two villages called Seiarauna-el-Bahri, i.e. Seiarauna at the river, and Seiarauna-el-Ghibli, i.e. upstream" (translated). The latter is now known as Ash Sharawinah al Qibliyah, El-Sharâwna el-Qiblîya or simply Al Sharauna among other variants, and is indeed directly across the Nile from Sebaiya (also called As Sibaiyyah and Al Sebaaia West City).  Smith and Lamanna (2005) stated the particular tooth they described was from "near Idfu in the Nile Valley of Egypt (Fig. 1, exact locality data are unknown; research in Palermo did not reveal a more accurate location)", but Idfu (also called Edfu) is 30 km to the southeast.  Gemmellaro states "the majority of the specimens came from [Seiarauna-el-Ghibli]. But a careful research recently conducted by myself on the abundant material donated by Cortese has allowed me to find all the types studied also in the locations of Gebel Nakheil (Kosseir-el-Khadim and Uadi-el-Anz mines) and of Gebel Duwi" (translated), suggesting no other localities were involved and perhaps 30 km was considered "near" by whoevever wrote that record.
Di Stefano (1919) first reported theropod material from Al Sharauna, collected by him in 1912 and also donated to the MGUP by Cortese between then and his publication- "In contact between the phosphates and the alternating marls, bones and quite a few dinosaurian teeth (Mosasaurus, Platecarpus, Megalosaurus, etc.) are found, which will be the subject of a special study."  That study was Gemmellaro (1921), who as noted above also discovered theropod material in the Gebel Duwi and Gebel Nakheil collections.  Unfortunately, Gemmellaro never specifies which of the three localities any of his discussed specimens is from, nor does he state how many teeth were in the MGUP collections.  Three teeth are figured, with those in figures 12 and 13 typically abelisaurid with low crowns serrated to the base both mesially and distally.  Curvature and crown height ratios are most similar to posterior dentary teeth of Majungasaurus.  Gemmellaro compares the teeth favorably to Majungasaurus syntypes FSL 92.306a and b and a Maevarano tooth figured by Thevenin 1906 (MNHN coll.).  A smaller, third tooth is illustrated as figure 14, said to be among "some which, although sharing some common features, differ in the shape of the crown which is not backward curved but is almost isosceles with the sides having a profile slightly convex or straight."  While Gemmellaro believed "such differences in shape and in dimensions between teeth has to be attributed to the diverse locations they occupied in the jaws, and also to the different age of the individuals whom the teeth belonged to", the mesiodistally narrower crown suggests another taxon such as a noasaurid, and that tooth is listed as Averostra indet. here.  Gemmellaro described two unguals and figured one.  While he compares them favorably to crenatissimus syntype FSL 92.290, the preserved section of the figured specimen is less tapered in side view with no obvious vascular groove, and this holds true as well for other Majungasaurus pedal unguals (e.g. FMNH PR 2434, MSNM V6418, V6419) as well as Masiakasaurus (e.g. FMNH PR 2135) and indeed most theropods.  Photos provided by Di Patti (pers. comm. 6-2023) show the figured element (MGUP MEGA004) is a sauropod pedal ungual while the other (MGUP MEGA005) compares well to an ankylopollexian manual ungual I.  They are referred to Titanosauria indet. and Hadrosauroidea indet. here based on age.
Smith and Lamanna (2006) described one of Gemmellaro's teeth in detail (MGUP MEGA002), although it is not one previously figured.  They identified it as abelisaurid based on "the distal curvature profile exhibits almost no curvature and is tilted slightly toward the apex in lateral view" (but this is not true of Gemmellaro's Figure 12), and as closer to Majungasaurus and Lameta AMNH 1753/1955 than Rugops, Rugops? sp. UCPC 10 or Bajo Barreal UNPSJB-PV 247 based on "mesial curvature profile begins at a strong curve at about 1/3 the crown height basal to the apex (but this is not true of Gemmellaro's Figure 12) and "the ... interdenticular sulci complex forms an intermediate condition between being absent and well developed" (unknown in Gemmellaro's figured specimens).  They find "The discriminant analysis (DA) correctly identified 96.6% of the teeth in the sample and classified MGUP MEGA002 as Majungasaurus" but note "the assignment of the Egyptian tooth to the genus Majungasaurus in particular is unlikely given that Africa and Madagascar were separated by the Mozambique Channel throughout the Cretaceous", and indeed the relatively low sample of abelisaurid teeth tested makes this questionable.  In fact he combination of stout shape plus concave basal distal edge with a convex apical distal edge is unlike figured Majungasaurus teeth.
Interestingly, the MGUP only has three teeth in their collection now (Di Patti, pers. comm. 6-2023), none of which are MGUP MEGA002 or match the three illustrated by Gemmellaro.  One (MGUP MEGA002 B) is abelisaurid based on the slightly convex distoapical edge, although the mesial edge is similar to Gemmellaro's Figure 12 instead of curving abruptly at a third of its height.  Marginal undulations are present as in some other abelisaurids (Abelisaurus, Chenanisaurus, Majungasaurus, Skorpiovenator).  There are ~10 mesial serrations per 5 mm and ~11 distal serrations.  The other two teeth (MGUP MEGA001 and MGUP MEGA003) are more partially preserved but of similar size and serration density (~10 distal serrations per 5 mm in MEGA001; ~10.5 mesial serrations per 5 mm in  MEGA003), and each shows marginal undulations as well, so they are tentatively placed as Abelisauridae here.  There are no precise locality data for any of them past Maastrichtian of Egypt.
References- Di Stefano, 1919. Osservazioni sul Cretaceo e sull'Eocene del Deserto Arabico di el-Sibaiya, nella valle del Nilo. Bollettino del R. Comitato Geologico d'Italia. Serie V(47), 1-39.
Gemmellaro, 1921. Rettili maëstrichtiani di Egitto. Giornale di Scienze Naturali ed Economiche. 32, 339-351.
Valentine, 1985. Structure and tectonics of the southern Gebel Duwi area, Eastern Desert of Egypt. Department of Geology and Geography, University of Massachusetts. Contribution No. 53, 141 pp.
Smith and Lamanna, 2006. An abelisaurid from the Late Cretaceous of Egypt: Implications for theropod biogeography. Naturwissenschaften. 93(5), 242-245.
Salama, Altoom, a Allam, Ajarem and Abd-Elhameed, 2021. Late Cretaceous anacoracid sharks (Squalicorax) from Duwi Formation, Gebel Duwi, central Eastern Desert, Egypt: Qualitative and quantitative analyses. Historical Biology. 33(11), 3056-3064.



Reference- de Souza-Júnior, Candeiro, da Silva Vidal, Brusatte and Mortimer, 2023. Abelisauroidea (Theropoda, Dinosauria) from Africa: A review of the fossil record. Papéis Avulsos de Zoologia. 63, e202363019.

7 comments:

  1. "Additionally, a review paper isn't really the place for new information or unpublished sources, so here are some extensive updates to poorly documented finds-"

    I don't necessarily agree. If it can be done in a way to appropriate credit the people working on the problem, it may end up being the only record that something was happening there. It's possible sometimes that a project may be abandoned for various reasons, and this may be the only evidence we have... common problem with WV fossils only showing up in abstracts, but not in published papers. :(

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  2. Why is Abelisauroidea universally used over Noasauroidea when the latter has five years' priority?

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    1. Because nobody had noticed that yet? (oof) But also it gets messy due to more recent disagreement on how to resolve Abelisaurus, Noasaurus and Ceratosaurus. If Noasaurus is outside Neoceratosauria (Ceratosaurus + Abelisaurus), then Abelisauroidea just sinks into Abelisauridae under what I think are the best definitions anyway. Honestly, this is probably a good reason to not use Abelisauroidea and use Abelisauria instead, since it's not like we have well supported taxa closer to abelisaurians but outside the Abelisaurus+Noasaurus group. Plus having an -ia group inside an -oidea group is always awkward.

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    2. Doesn't Eoabelisaurus usually end up there?

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    3. Sometimes, like in the Guemesia (2022) Filippi et al. based analysis and Saltriovenator (2018) Cau analysis, but it's closer to abelisaurids than noasaurids in others like the Limusaurus (2017) Stiegler analyses, Elemgasm (2022) Baiano analysis and Berthasaura (2021) Rauhut and Carrano based analysis.

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  3. Speaking of Abelisaurs, in Theropod Database the subfamilies Abelisaurinae and Carnotaurinae are inside the tribe Carnotaurini. Doesn't that violate ICZN rules?

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    1. I just apply the first published (non-problematic) definitions to what I think is the best topology. Sometimes that leads to silly outcomes like this, but nothing is official until registered with the Phylocode anyway so it doesn't matter until then. Think of it more of "these are the definitions everyone has proposed" instead of "these are the definitions I support."

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