Kem Kem Group

The Kem Kem Group (commonly known as the Kem Kem beds^[1]) is a geological group in the Kem Kem region of eastern Morocco, whose strata date back to the Cenomanian stage of the Late Cretaceous. Its strata are subdivided into two geological formations, with the lower Ifezouane Formation and the upper Aoufous Formation used for the strata on the eastern side of the Atlas Mountains (Tinghir), with the Gara Sbaa Formation and Douira Formation used in the southern Tafilalt region.^[2] It is exposed on an escarpment along the Algeria–Morocco border.

Kem Kem Group
Stratigraphic range: Cenomanian[1] ~100–95 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological group
Sub-units	Douira Formation, Gara Sbaa Formation
Underlies	Cenomanian-Turonian limestone platform (Akrabou Formation)
Lithology
Primary	Sandstone
Location
Coordinates	32°50′N 4°50′W
Approximate paleocoordinates	18.8°N 4.1°W / 18.8; -4.1
Region	Er Rachidia, Tafilalt
Country	Morocco
Extent	central and eastern Morocco north and south of the Pre-African Trough
Kem Kem Group (Morocco)

The unit unconformably overlies Paleozoic marine units of Cambrian, Silurian and Devonian ages and is itself capped by limestone platform rock of Cenomanian-Turonian age. It primarily consists of freshwater and estuarine deltaic deposits. The lower Gara Sbaa Formation primarily consists of fine and medium grained sandstone, while the Douira Formation consists of fining-upward, coarse-to-fine grained sandstones intercalated with siltstones, variegated mudstones, and occasional thin gypsiferous evaporites.^[1]

Dinosaur remains are among the fossils that have been recovered from the group.^[3] 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 have been separated by millions of years.^[4]

Although preserving a freshwater habitat located near a river delta (with some estuarine influence that increased over time as the sea level rose), the Kem Kem deposits were quickly submerged by the sea during the Cenomanian-Turonian boundary event, and are thus overlaid by the marine deposits of the younger latest Cenomanian and early-mid Turonian-aged Akrabou Formation, which was formerly also considered a member of the Kem Kem Group, but has been differentiated from it in more recent studies due to their differing paleoenvironments.^[1][5]

Vertebrate paleofauna

Cartilaginous fish

Cartilaginous fish
Genus	Species	Location	Material	Notes	Images
Acrodontidae indet.[1]	Indeterminate			Members of Hybodontoidea
Bahariyodon[1]	B. bartheli			A member of Hybodontoidea
Cenocarcharias[1]	C. tenuiplicatus		One tooth[1]	A member of the family Cretoxyrhinidae
Distobatus[1]	D. nutiae			A member of Hybodontoidea
Haimirichia[1]	H. amonensis		One tooth[1]	A mackerel shark
Marckgrafia[1]	M. lybica		13 teeth[1]	A member of Batoidea
Onchopristis	O. numida[6]			A rajiform ray[7]	Rostrum and teeth fossils from Onchopristis
Peyeria[1]	P. libyca		Three teeth[1]	A sawfish. Might be a junior synonym of Onchopristis numida.
Tribodus[1]	T. sp.			A member of Hybodontoidea

Ray-finned fish

Ray-finned fish
Genus	Species	Location	Material	Notes	Images
Adrianaichthys[1]	A. pankowskii		Isolated scales[8] and two skulls[9]	A member of Lepisosteiformes. Originally described as a species of Lepidotes, but subsequently transferred to a separate genus.[10]	Life restoration of Aidachar
Afrocascudo[11]	A. saharaensis			A neopterygiian fish, either an ancient loricariid catfish or a juvenile obaichthyid lepisosteiform.[12]
Agassizilia[13]	A. erfoudina			Possibly a member of the family Pycnodontidae.
Agoultichthys[1]	A. chattertoni			A long-bodied member of Actinopterygii of uncertain phylogenetic placement. Might be a member of the family Macrosemiidae[14] or Ophiopsiellidae.[15]
Aidachar	A. pankowskii			A member of Ichthyodectiformes
Bartschichthys[1]	B. sp.		Isolated pinnulae (spines that support each dorsal finlet)[1]	A cladistian
Bawitius	cf. B. sp.		Isolated scales and jaw fragments[8]	A cladistian
Calamopleurus[1]	C. africanus		A partial skull[1]	A member of Amiiformes
Concavotectum[1]	C. moroccensis			A member of Tselfatiiformes
Dentilepisosteus[1]	D. kemkemensis			A member of Lepisosteiformes
Diplomystus[1]	D. sp.			A deep-bodied teleost belonging to the group Clupeomorpha
Diplospondichthys[1]	D. moreaui			A member of Actinopterygii of uncertain phylogenetic placement, possibly a teleost
Erfoudichthys[1]	E. rosae		Isolated skull[1]	A small-bodied teleost of unknown affinity
Neoproscinetes[13]	N. africanus			A member of the family Pycnodontidae
Obaichthys	O. africanus		Isolated scales[8]	A member of Lepisosteiformes
Oniichthys	O. falipoui		Near complete skeleton including skull[8]	A member of Lepisosteiformes
Palaeonotopterus[1]	P. greenwoodi			A member of Osteoglossomorpha
Serenoichthys[1]	S. kemkemensis		Several articulated skeletons[1]	A small cladistian
Spinocaudichthys[1]	S. oumtkoutensis			An elongate freshwater acanthomorph
Stromerichthys	S. aethiopicus
Sudania[1]	S. sp.		An isolated pinnula[1]	A cladistian

Lobe-finned fish

Lobe-finned fish
Genus	Species	Location	Material	Notes	Images
Arganodus	A. tiguidiensis			A lungfish	Life restoration of Axelrodichthys The Queensland Lungfish, the only living member of Neoceratodus
Axelrodichthys[16]	A.? lavocati			A mawsoniid coelacanth; this species was previously assigned to Mawsonia, and its generic assignment is still not certain[17]
Neoceratodus	N. africanus			A lungfish

Amphibians

Amphibians
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Anura indet.[18]	Indeterminate		Douira Formation	Incomplete left ilium
Cretadhefdaa[18]	C. taouzensis		Douira Formation	Posterior portion of the skull, incomplete squamosal, incomplete maxilla, three incomplete presacral vertebrae, one incomplete sacral vertebra	A neobatrachian frog with possible hyloid affinities.
cf. Kababisha[19]	Indeterminate				A salamander belonging to the family Sirenidae
?Neobatrachia indet.[18]	Indeterminate		Douira Formation	Incomplete humerus	A frog, possibly a member of Ranoidea.
Oumtkoutia[19]	O. anae				A frog belonging to the family Pipidae

Lizards and snakes

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.

Lizards and snakes reported from the Continental Red Beds
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Bicuspidon	B. hogreli[20]				A polyglyphanodontid lizard.
Jeddaherdan[21]	J. aleadonta			Partial mandible with teeth.	An iguanian belonging to the group Acrodonta, possibly a relative of the uromastycine agamids. Argued by Vullo et al. (2022) to actually come from Quaternary beds, and to be based on a fossil material of a member of the genus Uromastyx.[22]
Lapparentophis	L. ragei[23]			Two isolated trunk vertebrae	An early snake.
Madtsoiidae indet.[19]	Indeterminate			Vertebrae[1]	An early snake.
?Nigerophiidae indet.[19]	Indeterminate			Dorsal vertebrae[1]	An early snake.
Norisophis[24]	N. begaa[24]			One posterior and two mid-trunk vertebrae	A stem-snake.
	Indeterminate[24]			A mid-trunk vertebra
Simoliophis[19]	cf. S. libycus			Vertebrae[1]	An early snake.

Plesiosaurs

Plesiosaurs
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Leptocleididae cf. Leptocleidus[25]	indeterminate

Turtles

Turtles reported from the Continental Red Beds
Genus	Species	Location	Stratigraphic position	Material	Notes
Dirqadim	D. schaefferi				A Euraxemydid
Galianemys	G. emringeri				A Cearachelyin
	G. whitei
Hamadachelys	H. escuilliei

Crocodylomorphs

A tooth enamel identified as cf. Sarcosuchus was discovered from the Ifezouane Formation.^[26]

Crocodylomorphs reported from the Continental Red Beds
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Aegisuchus	A. witmeri			"Partial braincase of a large individual with skull roof, temporal, and occipital regions."[27]	An aegyptosuchid that may be a synonym of Laganosuchus.[1]	Aegisuchus Araripesuchus Elosuchus cherifiensis Laganosuchus
Antaeusuchus[28]	A. taouzensis			Paired mandibles and a partial right mandible	A peirosaurid.
Araripesuchus	A. rattoides		Douira Formation
Elosuchus	E. cherifiensis		Gara Sbaa Formation Douira Formation		A pholidosaurid. The material may represent two different species.[1]
Hamadasuchus	H. rebouli		Gara Sbaa Formation Douira Formation?		A peirosaurid.
Kemkemia	K. auditorei	Errachidia Province, Morocco[29]		Known from an isolated caudal vertebra.[29]	Initially thought to be a neotheropod,[29] but subsequently discovered to be an indeterminate crocodyliform.[30]
Laganosuchus	L. thaumastos				A stomatosuchid.
Lavocatchampsa[31]	L. sigogneaurusselae			Anterior portion of a rostrum with mandible, with an almost complete dentition[31]	A candidodontid notosuchian.[31]

Dinosaurs

Indeterminate lithostrotian remains once misattributed to the Titanosauridae are present in the province of Ksar-es-Souk, Morocco.^[3]

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.

Ornithischians

Ornithischians reported from the Continental Red Beds
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Ankylosauria[1][32]	Indeterminate		Douira Formation	An isolated tooth.[1]	A probable ankylosaur[32]
Ornithopoda[33]	Indeterminate		Douira Formation	A large, clover-shaped, three-toed footprint.[1]	Comparable in size and shape to tracks typically attributed to Iguanodon.[33]

Sauropods

Sauropods reported from the Continental Red Beds
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Rebbachisaurus	R. garasbae	Ksar-es-Souk province, Morocco.[3]	Gara Sbaa Formation		A rebbachisaurid.	Rebbachisaurus garasbae
Somphospondyli[34]	Indeterminate			Anterior dorsal vertebra, partial right ischium[34]	The vertebra might belong to a basal titanosaurian, possibly distinct from Aegyptosaurus and Paralititan.[34] 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.[34]
Titanosauria[35][1]	Indeterminate		Ifezouane Formation Douira Formation	Isolated teeth, caudal vertebrae, a partial humerus, a tarsal bone and the proximal end of an ulna.[1]	Fossil material of one or more titanosaurian sauropods. Some fossils are indicative of large body size comparable to Paralititan stromeri.[1]

Theropods

Theropods reported from the Continental Red Beds
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Abelisauridae[36]	Indeterminate			Isolated teeth.[36][37] Partial right femur.[4] Partial right maxilla.[1] A cervical vertebra.[38] Left maxilla.[1]	Abelisaurid material belonging to one or two distinct taxa.[1]	Carcharodontosaurus saharicus Deltadromeus agilis Sigilmassasaurus Spinosaurus aegyptiacus reconstruction
Carcharodontosaurus[3]	C. saharicus[3]	Ksar-es-Souk province, Morocco.[3]	Douira Formation	Partial skull, including braincase, nasals, postorbitals, jugals, left lacrimal and right maxilla with most teeth.[39]	A carcharodontosaurid theropod.
Carcharodontosauridae[40]	Indeterminate	Southeast of Taouz, Errachidia Province	Ifezouane Formation	partial maxilla and partial jugal	A carcharodontosaurid theropod different from C. saharicus
Deltadromeus	D. agilis		Gara Sbaa Formation	"Partial skeleton, isolated limb elements."[41]	A noasaurid ceratosaurian or possible neovenatorid carnosaur. May be synonymous with Bahariasaurus.
Dromaeosauridae[36]	Indeterminate			Isolated teeth.[36]	Originally described as teeth of indeterminate dromaeosaurids. Hendrickx et al. (2024) reinterpreted this fossil material as teeth of abelisauroid theropods, including noasaurids and juvenile abelisaurids.[37]
cf. Elaphrosaurus	Indeterminate	Ksar-es-Souk province, Morocco.[3]			Fossils previously referred to cf. Elaphrosaurus are actually indeterminate theropod remains.
Noasauridae[38]	Indeterminate			An anterior cervical vertebra[38] Isolated teeth[37]
"Osteoporosia"[42]	"O. gigantea"[42]			A tooth and a possible neural arch from another specimen.[42]	A theropod, possibly synonymous with Sauroniops.[43]
Saurischia[44]	Indeterminate			An isolated cervical vertebra.[44]	An indeterminate saurischian.
Sauroniops[45]	S. pachytholus		Ifezouane Formation	"An isolated and almost complete left frontal,[46] and a possible tooth and neural arch from two other specimens."[43]	A carcharodontosaurid thought to be distinct from Carcharodontosaurus,[45][46] considered a nomen dubium by Kellerman et al.[47]
Sigilmassasaurus	S. brevicollis	Tafilalt Oasis region, Morocco.	Kem Kem Formation	A single neck vertebrae.	A controversial spinosaurid theropod.
Spinosaurus	S. aegyptiacus	Ksar-es-Souk province, Morocco.[3]	Douira Formation	Partial skeleton, including parts of the skull, neck, torso, and most of the tail and hind limbs. [48] Numerous isolated bones.	A spinosaurid theropod.

Pterosaurs

Pterosaurs of the Kem Kem Beds
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Afrotapejara[49]	A. zouhri[49]	Takmout	Ifezouane Formation	A fragment of bone interpreted as a fragment of anterior mandibular symphysis,[50] and additional jaw fragments that pertain to the rostrum as well as indeterminate jaw fragments.[2]	A tapejarid pterosaur. Originally believed to belong to either the family Thalassodromidae[51] or an additional specimen of Alanqa saharica.[52]	Afrotapejara zouhri Akharhynchus martilli Alanqa saharica Anhanguera Coloborhynchus Leptostomia Ornithocheirus
Akharhynchus[53]	A. martilli	Tafilalt	Ifezouane Formation	A fragment of the anterior part of the premaxillae	A tropeognathine anhanguerian.
Alanqa[51]	A. saharica[51]		Ifezouane Formation	The holotype is a mandibular symphysis, of different parts of the jaw	A pterosaur of uncertain phylogenetic placement, probably an azhdarchid.[2]
Anhanguera[54]	A. cf. piscator[54]		upper Ifezouane Formation	Partial mandibular symphysis[54]
Apatorhamphus[55]	A. gyrostega[55]		Ifezouane Formation	Partial rostrum and mandible, with additional referred jaw fragments[2]	A possible chaoyangopterid azhdarchoid pterosaur.[55] Originally believed to be a possible pteranodontid,[51] a possible dsungaripterid,[56] a possible non-azhdarchid azhdarchoid or nyctosaurid,[56] or a specimen of Alanqa saharica.[52]
Azhdarchidae indet.[56][2]	Indeterminate[56][2]			Numerous middle cervical vertebrae and a femur.[56][51][2]	Indicative of multiple taxa.[56] Some of these vertebrae may pertain to Alanqa saharica.[52][57]
Azhdarchoidea indet.	"Jaw morphotype A"[2]			Two jaw fragments[2]	Different from all named Kem Kem pterosaur taxa[2]
	"Jaw morphotype B"[2]			Partial mandible fragment[2]	Probably had a similarly long jaw to Leptostomia[2]
	"Jaw morphotype C"[2]			Partial jaw fragments[2]	May belong to Apatorhamphus or Xericeps[2]
	Indeterminate[2]			Five cervical vertebrae, a scapulocoracoid, two humeri, two ulnae, a metacarpal IV, and a tibiotarsus[2]
Coloborhynchus[54]	C. sp. A.[54]	Hassi El Begaa		Premaxillae fragment[54]	Possibly a specimen of Nicorhynchus fluviferox.[58]
Leptostomia[59]	L. begaaensis[59]	Aferdou N’ Chaft	upper Ifezouane Formation	Partial rostrum and partial mandibular synthesis[59]	A small, long-beaked pterosaur, likely a member of Azhdarchoidea.[59]
Nicorhynchus[58]	N. fluviferox[60][58]	Possibly Aferdou N’Chaft, Hassi El Begaa[58]	Ifezouane Formation	An anterior portion of the rostrum.[58]	Originally described as a species of Coloborhynchus[60] but subsequently transferred to the genus Nicorhynchus.
Ornithocheirus[54]	O. cf. simus.[54]		upper Ifezouane Formation	Premaxillae fragment[54]
Siroccopteryx[61]	S. moroccensis[61]			Anterior part of a rostrum	Classified by some authors as a species belonging to the genus Coloborhynchus.[51]
Xericeps	X. curvirostra	Aferdou N'Chaft	Ifezouane Formation	Mandibular symphysis and partial mandible[2]	An indeterminate azhdarchoid, possibly a chaoyangopterid.[2]

See also

• Earth sciences portal
• Paleontology portal
• Dinosaurs portal

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