Kem Kem Group

The Kem Kem Group (commonly known as the Kem Kem beds[2]) is a geological group along the Algeria–Morocco border in the Kem Kem region of eastern Morocco, whose strata date back to the Late Cretaceous. Its strata are subdivided into two geological formations, the older Douira Formation and younger Gara Sbaa Formation.[2]

Kem Kem Group
Stratigraphic range: Cenomanian[1]
~98–92.5 Ma
TypeGeological group
Sub-unitsDouira Formation, Gara Sbaa Formation
Lithology
PrimarySandstone
Location
RegionEr Rachidia, Tafilalt
Country Morocco
Extentcentral and eastern Morocco north and south of the Pre-African Trough

(A) Location of the Kem Kem Group; (B) Coeval sites in North Africa; (C) Key Cretaceous-aged outcrops

Dinosaur remains are among the fossils that have been recovered from the group.[1] Recent fossil evidence in the form of isolated large abelisaurid bones and comparisons with other similarly aged deposits elsewhere in Africa indicates that the fauna of the Kem Kem Group (specifically in regard to the numerous predatory theropod dinosaurs) may have been mixed together due to the harsh and changing geology of the region when in reality they would likely have preferred separate habitats and likely would be separated by millions of years.[3]

Vertebrate paleofauna

Fish

Fishes
GenusSpeciesLocationMaterialNotesImages
Acrodontidae indet.[2] Indeterminate Members of Hybodontoidea
Life restoration of Aidachar
Rostrum and teeth fossils from Onchopristis
Life restoration of Mawsonia
The Queensland Lungfish, the only living member of Neoceratodus
Adrianaichthys[2] A. pankowskii Isolated scales[4] and two skulls[5] A member of Lepisosteiformes. Originally described as a species of Lepidotes, but subsequently transferred to a separate genus.[6]
Agassizilia[7] A. erfoudina Possibly a member of the family Pycnodontidae.
Agoultichthys[2] A. chattertoni A long-bodied member of Actinopterygii of uncertain phylogenetic placement. Might be a member of the family Macrosemiidae[8] or Ophiopsiellidae.[9]
Aidachar A. pankowskii
Arganodus A. tiguidiensis
Bahariyodon[2] B. bartheli A member of Hybodontoidea
Bartschichthys[2] Bartschichthys sp. Isolated pinnulae (spines that support each dorsal finlet)[2] A cladistian
Bawitius cf. Bawitius sp. Isolated scales and jaw fragments[4]
Calamopleurus[2] C. africanus A partial skull[2] A member of Amiiformes
Cenocarcharias[2] C. tenuiplicatus One tooth[2] A member of the family Cretoxyrhinidae
Concavotectum[2] C. moroccensis A member of Tselfatiiformes
Dentilepisosteus[2] D. kemkemensis A member of Lepisosteiformes
Diplomystus[2] Diplomystus sp. A deep-bodied teleost belonging to the group Clupeomorpha
Diplospondichthys[2] D. moreaui A member of Actinopterygii of uncertain phylogenetic placement, possibly a teleost
Distobatus[2] D. nutiae A member of Hybodontoidea
Erfoudichthys[2] E. rosae Isolated skull[2] A small-bodied teleost of unknown affinity
Haimirichia[2] H. amonensis One tooth[2] A mackerel shark
Marckgrafia[2] M. lybica 13 teeth[2] A member of Batoidea
Mawsonia M. lavocati
Neoceratodus N. africanus
Neoproscinetes[7] N. africanus A member of the family Pycnodontidae
Obaichthys O. africanus Isolated scales[4] A member of Lepisosteiformes
Onchopristis O. numidus A giant sawfish[10]
Oniichthys O. falipoui Near complete skeleton including skull[4] A member of Lepisosteiformes
Palaeonotopterus[2] P. greenwoodi A member of Osteoglossomorpha
Peyeria[2] P. libyca Three teeth[2] A sawfish. Might be a junior synonym of Onchopristis numidus.
Serenoichthys[2] S kemkemensis Several articulated skeletons[2] A small cladistian
Spinocaudichthys[2] S. oumtkoutensis An elongate freshwater acanthomorph
Stromerichthys S. aethiopicus
Sudania[2] Sudania sp. An isolated pinnula[2] A cladistian
Tribodus[2] Tribodus sp. A member of Hybodontoidea

Amphibians

Amphibians
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Anura indet.[11] Indeterminate Partial braincase, jaw fragments and procoelous vertebrae[2] Fossil material probably pertaining to several species of non-pipid frogs.[2]
cf. Kababisha[11] Indeterminate A salamander belonging to the family Sirenidae
Oumtkoutia[11] O. anae A frog belonging to the family Pipidae

Lizards and snakes

Lizards and snakes reported from the Continental Red Beds
Genus Species Location Stratigraphic position Material Notes Images

Bicuspidon

Bicuspidon hogreli[12]

A polyglyphanodontid lizard.

Jeddaherdan[13]

Jeddaherdan aleadonta

Partial mandible with teeth.

An iguanian belonging to the group Acrodonta, possibly a relative of the uromasticine agamids.

Lapparentophis

Lapparentophis ragei[14]

Two isolated trunk vertebrae

An early snake.

Madtsoiidae indet.[11]

Indeterminate

Vertebrae[2]

An early snake.

?Nigerophiidae indet.[11]

Indeterminate

Dorsal vertebrae[2]

An early snake.

Norisophis[15]

Norisophis begaa[15]

One posterior and two mid-trunk vertebrae

A stem-snake.

Indeterminate[15]

A mid-trunk vertebra

Simoliophis[11]

cf. Simoliophis libycus

Vertebrae[2]

An early snake.

Crocodylomorphs

Crocodylomorphs reported from the Continental Red Beds
Genus Species Location Stratigraphic position Material Notes Images

Aegisuchus

Aegisuchus witmeri

"Partial braincase of a large individual with skull roof, temporal, and occipital regions."[16]

An aegyptosuchid.

Elosuchus cherifiensis

Araripesuchus

Araripesuchus rattoides

Elosuchus

Elosuchus cherifiensis

An Elosuchid.

Hamadasuchus

Hamadasuchus rebouli

A Peirosaurid.

Kemkemia

K. auditorei

Errachidia Province, Morocco[17]

Known from an isolated caudal vertebra.[17]

Initially thought to be a neotheropod,[17] but subsequently discovered to be an indeterminate crocodyliform.[18]

Laganosuchus

Laganosuchus maghrebensisis

A Stomatosuchid.

Lavocatchampsa[19]

Lavocatchampsa sigogneaurusselae

Anterior portion of a rostrum with mandible, with an almost complete dentition[19]

A candidodontid notosuchian.[19]

Dinosaurs

Indeterminate lithostrotian remains once misattributed to the Titanosauridae are present in the province of Ksar-es-Souk, Morocco.[1]

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Dinosaurs reported from the Continental Red Beds
Genus Species Location Stratigraphic position Material Notes Images

Abelisauridae indet.[20]

Indeterminate

Isolated teeth.[20]
Partial right femur.[21]

An indeterminate abelisaurid.

Carcharodontosaurus saharicus
Spinosaurus aegyptiacus reconstruction

Abelisauridae indet.[2]

Indeterminate

Partial right maxilla (UCPC 10)[2]

An indeterminate abelisaurid.

Carcharodontosaurus[1]

C. saharicus[1]

Ksar-es-Souk province, Morocco.[1]

A carcharodontosaurid theropod.

Deltadromeus

D. agilis

"Partial skeleton, isolated limb elements."[22]

A noasaurid ceratosaurian or possible neovenatorid carnosaur. May be synonymous with Bahariasaurus.

Dromaeosauridae indet.[20]

Indeterminate

Isolated teeth.[20]

An indeterminate dromaeosaurid.

cf. Elaphrosaurus

Indeterminate

Ksar-es-Souk province, Morocco.[1]

Fossils previously referred to cf. Elaphrosaurus are actually indeterminate theropod remains.

Noasauridae indet.[23]

Indeterminate

An anterior cervical vertebra[23]

Ornithischia indet.[2]

Indeterminate

An isolated tooth.[2]

A small-bodied ornithischian of uncertain phylogenetic placement, possibly a thyreophoran.[2]

Ornithopoda indet.[24]

Indeterminate

A large, clover-shaped, three-toed footprint.[2]

Comparable in size and shape to tracks typically attributed to Iguanodon.[24]

Rebbachisaurus

R. garasbae

Ksar-es-Souk province, Morocco.[1]

A rebbachisaurid.

Rugops

R. sp.

Left maxilla (MPUR NS 153/02) [23]

An abelisaurid theropod

Saurischia indet.[25]

Indeterminate

An isolated cervical vertebra.[25]

An indeterminate saurischian.

Sauroniops[26]

S. pachytholus

"An isolated and almost complete left frontal."[27]

A carcharodontosaurid distinct from Carcharodontosaurus.[26][27]

Sigilmassasaurus

S. brevicollis

Ksar-es-Souk province, Morocco.

Somphospondyli indet.[28]

Indeterminate

Anterior dorsal vertebra, partial right ischium[28]

The vertebra might belong to a basal titanosaurian, possibly distinct from Aegyptosaurus and Paralititan.[28] The ischium is not identifiable beyond Somphospondyli; it preserves numerous grooves and pits which might be feeding traces left by a very large non-avian theropod.[28]

Spinosaurus

S. aegyptiacus

Ksar-es-Souk province, Morocco.[1]

Theropoda indet.

Indeterminate

An ilium.[29]

A theropod dinosaur of uncertain phylogenetic placement. Originally classified as an abelisaur,[29] but subsequently argued to be a possible tetanuran,[30] or, specifically, a specimen of Spinosaurus aegyptiacus.[23]

Titanosauria indet.[31][2]

Indeterminate

Isolated teeth, caudal vertebrae, a partial humerus, a tarsal bone and the proximal end of an ulna.[2]

Fossil material pertaining to one or more titanosaurian sauropods. Some fossils are indicative of large body size comparable to Paralititan stromeri.[2]

Pterosaurs

Pterosaurs of the Kem Kem Beds
Genus Species Location Stratigraphic position Abundance Notes Images

Afrotapejara [32]

A. zouhri[32]

A fragment of bone originally interpreted as a fragment of anterior mandibular symphysis,[33] though it might pertain to the rostrum instead.[34]

A tapejarid pterosaur. Originally believed to belong to either the family Thalassodromidae[34] or an additional specimen of Alanqa saharica.[35]

Alanqa saharica

Alanqa[34]

A. saharica[34]

Anhanguera [36]

A. cf. piscator[36]

Partial mandibular symphysis[36]

Apatorhamphus[37]

A. gyrostega[37]

Partial rostrum and mandible[37]

A possible chaoyangopterid azhdarchoid pterosaur.[37] Originally believed to be a possible pteranodontid[34], a possible dsungaripterid[38], a possible non-azhdarchid azhdarchoid or nyctosaurid[38], or a specimen of Alanqa saharica.[35]

Azhdarchidae indet.[38]

Indeterminate[38]

Three middle cervical vertebrae.[38][34]

Averianov (2014) considered these vertebrae to pertain to Alanqa saharica,[35] although the vertebrae may be indicative of two taxa.[38]

Azhdarchoidea indet.[38]

Indeterminate[38]

Humerus.[38]

Averianov (2014) considered it to be a specimen of Alanqa saharica.[35]

Coloborhynchus[39] C. fluviferox[39]
C. sp. A.[36]
Hassi El Begaa Premaxillae fragment
Premaxillae fragment[36]

Ornithocheirus[36]

O. cf. simus.[36]

Premaxillae fragment[36]

Siroccopteryx[40]

S. moroccensis[40]

Classified by some authors as a species belonging to the genus Coloborhynchus.[34]

Xericeps X. curvirostra A mandible fragment

Turtles

Turtles reported from the Continental Red Beds
Genus Species Location Stratigraphic position Material Notes

Dirqadim

Dirqadim schaefferi

A Euraxemydid

Galianemys

G. emringeri

A Cearachelyin

G. whitei

Hamadachelys

Hamadachelys escuilliei

See also

  • Aoufous Formation, which lies within the Kem Kem Beds
  • List of dinosaur-bearing rock formations

References

  1. Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, Africa)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 604-605. ISBN 0-520-24209-2.
  2. Ibrahim, N.; Sereno, P.C.; Varricchio, D.J.; Martill, D.M.; Dutheil, D.B.; Unwin, D.M.; Baidder, L.; Larsson, H.C.E.; Zouhri, S.; Kaoukaya, A. (2020). "Geology and paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco". ZooKeys. 928: 1–216. doi:10.3897/zookeys.928.47517. PMC 7188693. PMID 32362741.
  3. Smith, Collin (2016-02-29). "Fossil find reveals just how big carnivorous dinosaur may have grown". Imperial News. Retrieved 2020-02-03.
  4. Cavin, Lionel; Boudad, Larbi; Tong, Haiyan; Läng, Emilie; Tabouelle, Jérôme; Vullo, Romain (2015). "Taxonomic Composition and Trophic Structure of the Continental Bony Fish Assemblage from the Early Late Cretaceous of Southeastern Morocco". PLOS One. 10 (5): e0125786. doi:10.1371/journal.pone.0125786. ISSN 1932-6203. PMC 4446216. PMID 26018561.
  5. https://palaeo-electronica.org/2011_1/239/239.pdf
  6. François J. Meunier; René-Paul Eustache; Didier Dutheil; Lionel Cavin (2016). "Histology of ganoid scales from the early Late Cretaceous of the Kem Kem beds, SE Morocco: systematic and evolutionary implications". Cybium. 40 (2): 121–132. doi:10.26028/cybium/2016-402-003.
  7. Samuel L.A. Cooper; David M. Martill (2020). "A diverse assemblage of pycnodont fishes (Actinopterygii, Pycnodontomorpha) from the mid-Cretaceous, continental Kem Kem beds of South-East Morocco". Cretaceous Research. 112: Article 104456. doi:10.1016/j.cretres.2020.104456.
  8. Alison M. Murray; Mark V. H. Wilson (2009). "A new Late Cretaceous macrosemiid fish (Neopterygii, Halecostomi) from Morocco, with temporal and geographical range extensions for the family". Palaeontology. 52 (2): 429–440. doi:10.1111/j.1475-4983.2009.00851.x.
  9. Martin Ebert (2018). "Cerinichthys koelblae, gen. et sp. nov., from the Upper Jurassic of Cerin, France, and its phylogenetic setting, leading to a reassessment of the phylogenetic relationships of Halecomorphi (Actinopterygii)". Journal of Vertebrate Paleontology. 38 (1): e1420071. doi:10.1080/02724634.2017.1420071.
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  15. Catherine G. Klein; Nicholas R. Longrich; Nizar Ibrahim; Samir Zouhri; David M. Martill (2017). "A new basal snake from the mid-Cretaceous of Morocco" (PDF). Cretaceous Research. 72: 134–141. doi:10.1016/j.cretres.2016.12.001.
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  18. Lio, G., Agnolin, F., Cau, A. and Maganuco, S. (2012). "Crocodyliform affinities for Kemkemia auditorei Cau and Maganuco, 2009, from the Late Cretaceous of Morocco." Atti della Società Italiana di Scienze Naturali e del Museo di Storia Naturale di Milano, 153 (I), s. 119–126.
  19. Jeremy E. Martin; France De Lapparent De Broin (2016). "A miniature notosuchian with multicuspid teeth from the Cretaceous of Morocco" (PDF). Journal of Vertebrate Paleontology. 36 (6): e1211534. doi:10.1080/02724634.2016.1211534.
  20. Ute Richter; Alexander Mudroch; Lisa G. Buckley (2013). "Isolated theropod teeth from the Kem Kem Beds (Early Cenomanian) near Taouz, Morocco". Paläontologische Zeitschrift. 87 (2): 291–309. doi:10.1007/s12542-012-0153-1.
  21. Alfio Alessandro Chiarenza; Andrea Cau (2016). "A large abelisaurid (Dinosauria, Theropoda) from Morocco and comments on the Cenomanian theropods from North Africa". PeerJ. 4: e1754. doi:10.7717/peerj.1754. PMC 4782726. PMID 26966675.
  22. "Table 4.1," in Weishampel, et al. (2004). Page 76.
  23. Robert S.H. Smyth; Nizar Ibrahim; Alexander Kao; David M. Martill (2019). "Abelisauroid cervical vertebrae from the Cretaceous Kem Kem beds of Southern Morocco and a review of Kem Kem abelisauroids". Cretaceous Research. 108: 104330. doi:10.1016/j.cretres.2019.104330.
  24. Nizar Ibrahim; David J. Varricchio; Paul C. Sereno; Jeff A. Wilson; Didier B. Dutheil; David M. Martill; Lahssen Baidder; Samir Zouhri (2014). "Dinosaur footprints and other ichnofauna from the Cretaceous Kem Kem beds of Morocco". PLOS ONE. 9 (6): e90751. doi:10.1371/journal.pone.0090751. PMC 3946209. PMID 24603467.
  25. B. McFeeters (2013). "Bone "taxon" B: Reevaluation of a supposed small theropod dinosaur from the mid-Cretaceous of Morocco". Kirtlandia. 58: 38–41.
  26. Andrea Cau; Fabio M. Dalla Vecchia; Matteo Fabbri (2012). "A thick-skulled theropod (Dinosauria, Saurischia) from the Upper Cretaceous of Morocco with implications for carcharodontosaurid cranial evolution". Cretaceous Research. 40: 251–260. doi:10.1016/j.cretres.2012.09.002.
  27. Andrea Cau; Fabio Marco Dalla Vecchia; Matteo Fabbri (2012). "Evidence of a new carcharodontosaurid from the Upper Cretaceous of Morocco". Acta Palaeontologica Polonica. 57 (3): 661–665. doi:10.4202/app.2011.0043. Archived from the original on 2012-11-08.
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  29. Slimane Zitouni; Christian Laurent; Gareth Dyke; Nour-Eddine Jalil (2019). "An abelisaurid (Dinosauria: Theropoda) ilium from the Upper Cretaceous (Cenomanian) of the Kem Kem beds, Morocco". PLOS One. 14 (4): e0214055. Bibcode:2019PLoSO..1414055Z. doi:10.1371/journal.pone.0214055. PMC 6445567. PMID 30939139.
  30. Elisabete Malafaia; José Miguel Gasulla; Fernando Escaso; Iván Narváez; José Luis Sanz; Francisco Ortega (2019). "A new spinosaurid theropod (Dinosauria: Megalosauroidea) from the late Barremian of Vallibona, Spain: Implications for spinosaurid diversity in the Early Cretaceous of the Iberian Peninsula". Cretaceous Research. 106: Article 104221. doi:10.1016/j.cretres.2019.104221.
  31. Nizar Ibrahim; Cristiano Dal Sasso; Simone Maganuco; Matteo Fabbri; David M. Martill; Eric Gorscak; Matthew C. Lamanna (2016). "Evidence of a derived titanosaurian (Dinosauria, Sauropoda) in the "Kem Kem beds" of Morocco, with comments on sauropod paleoecology in the Cretaceous of Africa". New Mexico Museum of Natural History and Science Bulletin. 71: 149–159.
  32. David M. Martill; Roy Smith; David M. Unwin; Alexander Kao; James McPhee; Nizar Ibrahim (2020). "A new tapejarid (Pterosauria, Azhdarchoidea) from the mid-Cretaceous Kem Kem beds of Takmout, southern Morocco". Cretaceous Research. 112: Article 104424. doi:10.1016/j.cretres.2020.104424.
  33. Peter Wellnhofer; Eric Buffetaut (1999). "Pterosaur remains from the Cretaceous of Morocco". Paläontologische Zeitschrift. 73 (1–2): 133–142. doi:10.1007/BF02987987.
  34. Ibrahim, N.; Unwin, D.M.; Martill, D.M.; Baidder, L.; Zouhri, S. (2010). "A New Pterosaur (Pterodactyloidea: Azhdarchidae) from the Upper Cretaceous of Morocco". PLOS ONE. 5 (5): e10875. Bibcode:2010PLoSO...510875I. doi:10.1371/journal.pone.0010875. PMC 2877115. PMID 20520782.
  35. Alexander Averianov (2014). "Review of taxonomy, geographic distribution, and paleoenvironments of Azhdarchidae (Pterosauria)". ZooKeys (432): 1–107. doi:10.3897/zookeys.432.7913. PMC 4141157. PMID 25152671.
  36. Megan L. Jacobs; David M. Martill; David M. Unwin; Nizar Ibrahim; Samir Zouhri; Nicholas R. Longrich (2020). "New toothed pterosaurs (Pterosauria: Ornithocheiridae) from the middle Cretaceous Kem Kem beds of Morocco and implications for pterosaur palaeobiogeography and diversity". Cretaceous Research. 110: Article 104413. doi:10.1016/j.cretres.2020.104413.
  37. James McPhee; Nizar Ibrahim; Alex Kao; David M. Unwin; Roy Smith; David M. Martill (2020). "A new ?chaoyangopterid (Pterosauria: Pterodactyloidea) from the Cretaceous Kem Kem beds of Southern Morocco". Cretaceous Research. 110: Article 104410. doi:10.1016/j.cretres.2020.104410.
  38. Taissa Rodrigues; Alexander W. A. Kellner; Bryn J. Mader; Dale A. Russell (2011). "New pterosaur specimens from the Kem Kem beds (Upper Cretaceous, Cenomanian) of Morocco". Rivista Italiana di Paleontologia e Stratigrafia. 117 (1): 149–160. doi:10.13130/2039-4942/5967.
  39. Jacobs, Megan L.; Martill, David M.; Ibrahim, Nizar; Longrich, Nick (March 2019). "A new species of Coloborhynchus (Pterosauria, Ornithocheiridae) from the mid-Cretaceous of North Africa". Cretaceous Research. 95: 77–88. doi:10.1016/j.cretres.2018.10.018. ISSN 0195-6671.
  40. Rodrigues, Taissa; Kellner, Alexander W. A (2008). "Review of the pterodactyloid pterosaur Coloborhynchus" (PDF). Zitteliana. B 28: 219–228.
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