El Mers Group

{{Short description|Geological group in the Middle Atlas of Morocco}}

{{Infobox rockunit

| name = El Mers Group

| period = Bathonian

| age = Bajocian-Callovian
~{{fossil range|168|161}}

| image = {{Multiple image

| perrow = 2/2/2

| width = 135

| caption_align = center

| image1 = El Mers I Formation Thaghzout river canyon.jpg

| caption1 = El Mers I Formation at Thaghzout river canyon

| image2 = El Mers II Formation El Mers river bed 1.jpg

| caption2 = El Mers II along the El Mers river

| image3 = El Mers II Formation El Mers river bed 2.jpg

| caption3 = El Mers II along the El Mers river

| image4 = Thyreosaurus excavation site.jpg

| caption4 = El Mers III Dinosaur Bearing beds

| border = infobox

}}

| imagesize =

| caption =

| type = Group

| prilithology = Marl, gypsum (only in unit 3)

| otherlithology = Sandstone, limestone

| unitof =

| subunits = El Mers Formations 1–3

| underlies = Unconformity with Barremian or Plio-Pleistocene sediments

| overlies = Ich Timellaline–Bou Akrabene Formation

| thickness = Over {{convert|500|m|ft|abbr=on}}

| area =

| map = {{Location map+ | Morocco

| relief = 1

| width = 250

| float = center

| places =

{{Location map~ | Morocco

| lat_deg = 33.5

| lon_deg = -4.3

| mark = Blue pog.svg

| marksize = 12

}}

| map_caption =

| location =

| coordinates = {{coord|33.5|N|4.3|W|display=inline,title}}

| paleocoordinates = {{coord|28.3|N|2.0|W|display=inline}}

| region = Boulemane and Azilal Provinces

| country = Morocco

| extent = Middle Atlas

| namedfor =

| namedby =

| year_ts =

| location_ts =

| coordinates_ts =

| paleocoordinates_ts =

| region_ts =

| country_ts =

| thickness_ts =

}}

The El Mers Group is a geological group in the Middle Atlas of Morocco. It is subdivided into three formations named the El Mers I, II, and III Formations, respectively. It is a marine deposit primarily consisting of marl, with gypsum present in the upper part of unit 3. It is the lateral equivalent of the terrestrial Guettioua Sandstone. Dinosaur remains are among the fossils that have been recovered from the group, most notably those of sauropods and the unusual thyreophorans Adratiklit, Thyreosaurus, and Spicomellus. This formation records a series of coastal to shallow marine settings of Middle Jurassic (with an age of Bajocian-Bathonian for El Mers 1 and a Bathonian-Callovian? for El Mers II-III), based on detailed stratigraphical biomarkers such as ammonites or Foranimifera.{{Cite journal |last=Khaffou |first=Hanane |last2=Hssaida |first2=Touria |last3=Oukassou |first3=Mostafa |last4=Maatouf |first4=Wafaa |last5=Afenzar |first5=Abdelkrim |last6=Zafaty |first6=Omar |last7=Chakir |first7=Sara |last8=Jaydawi |first8=Soukaina |last9=Chafai |first9=Khaoula |last10=Charrière |first10=André |date=2023 |title=Bajocian–Bathonian dinoflagellate cyst assemblages from the Middle Atlas, Morocco: Palynostratigraphic and paleoenvironmental implications |url=https://doi.org/10.1016/j.revpalbo.2023.104862 |journal=Review of Palaeobotany and Palynology |volume=312 |pages=104862 |doi=10.1016/j.revpalbo.2023.104862 |issn=0034-6667}}

Paleoenvironment

File:Staying Still 110 - Coorong.jpg.]]

The El Mers formations are composed primarily of marls with intermittent layers of limestone and sandstone, characterized by abundant organic matter and benthic fauna.{{Cite journal|last1=Oukassou|first1=M.|last2=Boumir|first2=Kh.|last3=Benshili|first3=Kh.|last4=Ouarhache|first4=D.|last5=Lagnaoui|first5=A.|last6=Charrière|first6=A.|date=June 2019|title=The Tichoukt Massif: a Geotouristic Play in the Folded Middle Atlas (Morocco)|journal=Geoheritage|volume=11|issue=2|pages=371–379|doi=10.1007/s12371-018-0287-y|bibcode=2019Geohe..11..371O |s2cid=134800520 |issn=1867-2477}} It is delineated into five distinct members, each exhibiting diverse lithological characteristics. The three members comprise a combination of layers of marls, sandstones, and limestones, marked by various unique fossils and organic materials. Sedimentary discontinuities reveal deltaic sequences that exhibit varying sedimentary structures and lithological compositions, reflecting dynamic depositional environments ranging from subtidal to continental. The facies associations within the El Mers Group are organized into elementary and mesosequences, delineating the transition from prodelta to deltaic plain environments. These sequences capture the evolution of tidal regimes and depositional dynamics.{{Cite journal |last1=Soufiani |first1=N. |last2=Fedan |first2=B. |date=2002 |title=Les dépôts bathoniens du synclinal d'El Mers (Moyen Atlas, Maroc): unités formationnelles, analyse et cadre géodynamique |url=http://www.israbat.ac.ma/wp-content/uploads/2015/03/01-%20Soufiani%20et%20al.%20(01-14).pdf |journal=Bulletin de l'Institut scientifique |volume=24 |issue=6 |pages=1–14}}{{Cite journal |last=Dresnay |first=Renaud du |date=1963-01-01 |title=Donnees stratigraphiques complementaires sur le Jurassique moyen des synclinaux d'El Mers et de Skoura (Moyen-Atlas, Maroc) |url=https://pubs.geoscienceworld.org/sgf/bsgf/article-abstract/S7-V/6/883/518424/Donnees-stratigraphiques-complementaires-sur-le |journal=Bulletin de la Société Géologique de France |volume=S7-V |issue=6 |pages=883–900 |doi=10.2113/gssgfbull.S7-V.6.883 |issn=0037-9409}}

During the Bajocian-Bathonian transition the local faices paint a picture of a dynamic paleoenvironment, where the interplay between land and sea was pronounced. This setting oscillated between a proximal continental shelf, marked by significant terrestrial input, and episodic marine incursions that suggest fluctuating sea levels. The lower parts of the section hint at shallow, sometimes oxygen-deprived, stagnant waters, much like modern lagoon or restricted bays where circulation is limited. Upwards there are signs of marine influence growing stronger, particularly at the base of "Interval C", where a notable sea-level rise seems to have occurred, akin to what we might see on today's outer continental shelves, like those in the North Sea, where marine life diversity peaks, specially Bivalves and Ammonites. However, this marine dominance is not consistent, reverting back to a more coastal, land-influenced environment towards the top, similar to modern deltaic regions where riverine and marine waters mix, such as the Louisiana coast or the Coorong National Park. The environment would have experienced variable salinity, much like estuaries where fresh and marine waters blend, affecting the types of biota that could thrive.

The shifts in facies and microfauna evolution in the area revelated intriguing patterns, from the establishment of initial supratidal environments characterized by charophytic marls and ostracod limestones followed by a resurgence of marine conditions, evident from the reappearance of coastal facies and the diversification of ostracod faunas, indicating a significant transgressive phase during the Upper Bathonian–Lower Callovian period. While in the Central High Atlas marine influences ceased by the Upper Bajocian–Lower Bathonian giving way to continental red layers, in the Middle Atlas marine influences persisted until the Upper Bathonian–Lower Callovian boundary, indicating a diachronic filling of the Atlas gulfs towards the Tethyan domain from west to east.{{Cite journal |last1=Charrière |first1=André |last2=Dépêche |first2=Françoise |last3=Feist |first3=Monique |last4=Grambast-Fessard |first4=Nicole |last5=Jaffrezo |first5=Michel |last6=Peybernès |first6=Bernard |last7=Ramalho |first7=Miguel |date=1994 |title=Microfaunes, microflores et paléoenvironnements successifs dans la formation d'El Mers (Bathonien-?Callovien) du synclinal de Skoura (Moyen-Atlas, Maroc) |url=http://dx.doi.org/10.1016/s0016-6995(94)80002-2 |journal=Geobios |volume=27 |issue=2 |pages=157–174 |doi=10.1016/s0016-6995(94)80002-2 |bibcode=1994Geobi..27..157C |issn=0016-6995}}

Fossils

= Foraminifera =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#D1FFCF;" |Bullopora

| style="background:#D1FFCF;" |

B. tuberculata

| style="background:#D1FFCF;" |

SW part of the Skoura syncline

| style="background:#D1FFCF;" |Tests/Shells

| style="background:#D1FFCF;" |A benthic foraminiferan of the family Polymorphinidae

| style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Pfenderella

| style="background:#D1FFCF;" |

P. cf. arabica

| style="background:#D1FFCF;" |

SW part of the Skoura syncline

| style="background:#D1FFCF;" |Tests/Shells

| style="background:#D1FFCF;" |A benthic foraminiferan of the family Pfenderininae

| style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Praekurnubia

| style="background:#D1FFCF;" |

P. crusei

| style="background:#D1FFCF;" |

SW part of the Skoura syncline

| style="background:#D1FFCF;" |Tests/Shells

| style="background:#D1FFCF;" |A benthic foraminiferan of the family Pfenderinidae; a genus found in the Tethys between Bajocian and Oxfordian-aged layers

| style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Pseudocyclammina

| style="background:#D1FFCF;" |

P. maynci

| style="background:#D1FFCF;" |

SW part of the Skoura syncline

| style="background:#D1FFCF;" |Tests/Shells

| style="background:#D1FFCF;" |A benthic foraminiferan of the family Hauraniidae

| style="background:#D1FFCF;" |

= Dinoflajellates =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#D1FFCF;" |Aldorfia

| style="background:#D1FFCF;" |

A. aldorfensis

| style="background:#D1FFCF;" |

FD section, Skoura Syncline

| style="background:#D1FFCF;" |Cysts

| style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

| style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Cribroperidinium

|style="background:#D1FFCF;" |

C. crispum
C. venustum

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Ctenidodinium

|style="background:#D1FFCF;" |

C. combazii
C. continuum
C. cornigerum

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate, incertae sedis

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Dichadogonyaulax

|style="background:#D1FFCF;" |

D. sellwoodii

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate, incertae sedis

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Korystocysta

|style="background:#D1FFCF;" |

K. gochtii
K. pachyderma

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Meiourogonyaulax

|style="background:#D1FFCF;" |

M. caytonensis
M. reticulata
M. valensii

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Nannoceratopsis

|style="background:#D1FFCF;" |

N. deflandrei

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Nannoceratopsiaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Pareodinia

|style="background:#D1FFCF;" |

P. ceratophora

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Pareodiniaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Rhynchodiniopsis

|style="background:#D1FFCF;" |

R. cladophora

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Trichodinium

|style="background:#D1FFCF;" |

T. scarburghense

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Tubotuberella

|style="background:#D1FFCF;" |

T. dangeardii

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Wanaea

|style="background:#D1FFCF;" |

W. acollaris
W. indotata
W. verrucosa

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate of the family Gonyaulacaceae

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Willeidinum

|style="background:#D1FFCF;" |

W. spp.

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Cysts

|style="background:#D1FFCF;" |A Dinoflajellate, incertae sedis

|style="background:#D1FFCF;" |

= Brachiopoda =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

Formosarhynchia

F. (Rhynchonella?) dumortieri

El Mers

|Isolated shells

|A branchipod of the family Rhynchonellidae

|File:Rhynchonella sp.4 - Jurasico.JPG

= Ostracoda =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

Cytherella

C. index

Ait Hammou

|Valves

|A freshwater/brackish ostracod of the family Cytherellidae

Fastigatocythere

F. aff. brentonensis

Ait Hammou

|Valves

|A freshwater/brackish ostracod of the family Progonocytheridae

Kinkelinella

K. aff. triangula

Ait Hammou

|Valves

|A freshwater ostracod of the family Progonocytheridae

Metacypris

M. spp.

Ait Hammou

|Valves

|A freshwater ostracod of the family Limnocytheridae. Local members of the genus genus would not be confined to limnic environments, but would be euryhaline or brackish, since they disappear when faunal diversity is at its maximum.

Procytheridea

P. ihopyensis

Ait Hammou

|Valves

|A freshwater ostracod of the family Schulerideidae

= Xiphosura =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#FEF6E4;" |Selenichnites{{Cite journal|last1=Oukassou|first1=Mostafa|last2=Charrière|first2=André|last3=Lagnaoui|first3=Abdelouahed|last4=Gibb|first4=Stacey|last5=Michard|first5=André|last6=Saddiqi|first6=Omar|date=April 2016|title=First occurrence of the Ichnogenus Selenichnites from the Middle Jurassic Strata of the Skoura Syncline (Middle Atlas, Morocco); Palaeoecological and palaeoenvironmental context|journal=Comptes Rendus Palevol|volume=15|issue=5|pages=461–471|doi=10.1016/j.crpv.2015.09.013|bibcode=2016CRPal..15..461O |doi-access=free}}

| style="background:#FEF6E4;" |

S. tesiltus
S. isp.

| style="background:#FEF6E4;" |

Skoura Syncline
Taferdouste

| style="background:#FEF6E4;" |Isolated crescent-shaped trace fossils

| style="background:#FEF6E4;" |Traces of xiphosurans, representing the second occurrence of this ichnogenus in Morocco

| style="background:#FEF6E4;" |File:Horseshoe crab (62577).jpg

= Mollusca =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

Cadomites

C. bremeri
C. cf. bremeri

East Skoura syncline

|Isolated shells

|An ammonite of the family Stephanoceratidae and indicator of the Bathonian age

|File:31 - Muséum de Toulouse - Cadomites deslongchampsii - Bayeux Calvados France.jpg

Cercomya

C. undulata

El Mers

|Isolated shells

|A marine clam of the family Laternulidae

Choffatia

C. cf. urinacensis

East Skoura syncline

|Isolated shells

|An ammonite of the family Perisphinctidae and indicator of the Callovian age

Corbula

C. pectinata

Aït Kermouss

|Isolated shells

|A marine clam of the family Corbulidae

Clydoniceras

C. discus

Tamguert n'Tarit
Tizi n'Juillerh

|Isolated shells

|An ammonite of the family Clydoniceratidae

Eomiodon

E. angulatus

El Mers

|Isolated Shells

|A marine clam of the family Neomiodontidae

Isognomon

I. (Mythiloperna) murchisoni

El Mers

|Isolated shells

|A marine oyster of the family Malleidae

|File:Isognomon dunkeri 02.jpg)]]

Lima

L. (Plagiostoma) subcardiformis

Aït Kermouss

|Isolated shells

|A marine file clam of the family Limidae

|File:Lima (YPM IZ 049863).jpeg)]]

Lopha

L. costata

Aït Kermouss

|Isolated shells

|A marine oyster of the family Ostreidae

|File:Lopha cristagalli.jpg)]]

Modiolus

M. imbricatus
M. cf. bipartitus

Aït Kermouss
El Mers
Tamguert n'Tarit

|Isolated shells

|A marine mussel of the family Mytilidae

|File:Modiolus sp. - Tromsø, Norway 2023-07-09 (01).jpg

Morphoceras

M. macrescens

East Skoura syncline

|Isolated shells

|An ammonite of the family Morphoceratidae and indicator of the Bathonian age

Mytilus

M. (Falcimytilus) tumidus

Aït Kermouss

|Isolated shells

|A marine mussel of the family Mytilidae

|File:Miesmuscheln Mytilus 2.jpg

Nucula

N. (Paleonucula) waltoni

El Mers

|Isolated shells

|A marine nut clam of the family Nuculanidae

|File:Nucula delphinodonta (YPM IZ 032764).jpeg)]]

Oraniceras

O. sp.

East Skoura syncline

|Isolated shells

|An ammonite of the family Parkinsoniidae and indicator of the Bathonian age

Orionoides

O. cf. pseudorion

East Skoura syncline

|Isolated shells

|An ammonite of the family Perisphinctidae

Ostrea

O. sandalina
O. (Liostrea) hebridica

Aït Kermouss
El Mers
Tamguert n'Tarit

|Isolated shells

|A marine oyster of the family Ostreidae

|File:Oyster.jpg

Paracenoceras

P. sp.

Aït Kermouss

|Isolated shells

|A Nautilidan of the family Paracenoceratidae

|File:Paracenoceras sp.jpg

Parkinsonia

P. sp.

Skoura syncline

|Isolated shells

|An ammonite of the family Parkinsoniidae and indicator of the Bajocian age for the lower portions of the Group

|File:Parkinsonia parkinsoni NHM.jpg

Protocardia

P. tikechkachensis

El Mers
Tamguert n'Tarit

|Isolated shells

|A marine cockle of the family Cardiidae

= Echinoderms =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

Acrosalenia

A. spinosa

El Mers
Ich Timellaline

|Isolated Individuals

|An Echinoidean of the family Acrosaleniidae

Hemicidaris

H. jauberti
H. cf. icaunensis

Ich Timellaline

|Isolated Individuals

|An Echinoidean of the family Hemicidaridae

|File:Hemicidaris crenularis FOS 2333 - 1.jpg

= Fishes =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

Lepidotes{{Cite journal |last=Beltan |first=Laurence |date=1957-01-01 |title=Etude d'un neurocrane de Lepidotes du Bathonien du Maroc |url=http://dx.doi.org/10.2113/gssgfbull.s6-vii.8-9.1091 |journal=Bulletin de la Société Géologique de France |volume=S6-VII |issue=8–9 |pages=1091–1106 |doi=10.2113/gssgfbull.s6-vii.8-9.1091 |issn=1777-5817}}

L. spp.

Ait Hammou
Djmila
Oued El Mers
Tizi n'Juillerh

|Cranial material, isolated teeth and scales

|A marine/brackish bony fish of the family Lepidotidae

|File:Lepidotes sp. - Naturhistorisches Museum, Braunschweig, Germany - DSC05183.JPG

Scheenstia

S. cf. mantelli

Oued El Mers

|Partial specimen wirth cranial material

|A marine/brackish bony fish of the family Lepidotidae

|File:Scheenstia maximus.jpg

= Testudinata =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

Testudinata{{Cite journal |last=Lapparent |first=A. F. d. |date=1955 |title=Étude paléontologique des vertébrés du Jurassique d'El Mers (Moyen Atlas) [Paleontological study of the Jurassic veretebrates from El Mers (Middle Atlas)] |url=https://search.worldcat.org/es/title/Etude-paleontologique-des-vertebres-du-jurrassique-d'El-Mers-(Moyen-Atlas)/oclc/17293965 |journal=Notes et Mémoires du Service Géologique du Maroc |volume=124 |issue=1 |pages=1–36}}{{Cite journal |last1=Termier |first1=H. |last2=Gubler |first2=J. |last3=Lapparent |first3=A. F. |date=1940 |title=Reptiles et Poissons du Bathonien d'El-Mers (Moyen-Atlas marocain) [Reptiles and fishes from the Bathonian of El Mers (Moroccan Middle Atlas)]. |url=https://naturalhistory.si.edu/sites/default/files/media/translated_publications/Termier%26amp%3B_40a.pdf |journal=Comptes Rendus de l'Académie des Sciences de Paris |volume=210 |issue=3 |pages=768–770}}

Indeterminate

Tamguert n'Tarit
Tizi n'Juillerh

|Very numerous debris: escutcheons, plates, vertebrae, ribs, long bones

|Turtle remains of uncertain affinity

= Crocodylomorpha =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#FEF6E4;" |Hatcherichnus{{Cite journal |last1=Amzil |first1=Mustapha |last2=Oukassou |first2=Mostafa |last3=Lallensack |first3=Jens N. |last4=Klein |first4=Hendrik |last5=Zafaty |first5=Omar |last6=Saber |first6=Hafid |last7=Charrière |first7=André |last8=Meyer |first8=Christian |last9=Gierliński |first9=Gerard D. |date=2024 |title=New dinosaur tracks from the Middle Jurassic red beds of the Middle Atlas (Morocco): Application of photogrammetry to ichnology and conservation of geological heritage |url=https://www.sciencedirect.com/science/article/pii/S0016787824000373 |journal=Proceedings of the Geologists' Association |volume=22 |issue=3 |pages=12–31|doi=10.1016/j.pgeola.2024.06.004 }}

| style="background:#FEF6E4;" |

H. ispp.

| style="background:#FEF6E4;" |

Inzar O'Founass

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Indeterminate Crocodrylomorph Tracks

| style="background:#FEF6E4;" |

style="background:#fbdddb;" |

"Megalosaurus"

| style="background:#fbdddb;" |

"M." mersensis

| style="background:#fbdddb;" |

Botane
Tizi n'Juillerh

| style="background:#fbdddb;" |

Isolated teeth and vertebra

| style="background:#fbdddb;" |

A marine crocodylomorph of the family Teleosauridae. Mistaken as Theropod remains in the past.{{Cite journal |last=Chabli |first=S. |date=1986 |title=Données nouvelles sur un «Dinosaurien» jurassique moyen du Maroc: Megalosaurus mersensis Lapparent 1955, et sur les Megalasaurides en Sénégal |url=https://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=8370587 |journal=Les dinosaures de la Chine à la France |volume=1 |issue=2 |pages=65–72}}

| style="background:#fbdddb;" |

Steneosaurus?

S.? spp.

Bou Iferaoun
Botane
Darak
Djmila
Oued Tamemecht
Tamguert r'Tane
Tirardine
Tissenfelt

Isolated teeth, cranial and postcranial material, both isolated and semi-articulated

A marine crocodylomorph of the family Teleosauridae. The referral to the genus Steneosaurus should be taken with caution, as this genus was overlumped.

=Dinosauria=

== Theropoda ==

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#FEF6E4;" |Carmelopodus

| style="background:#FEF6E4;" |

cf.C. isp.

| style="background:#FEF6E4;" |

Tassmante O'Moche

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Theropod tracks of uncertain affinity, suggested to come from Ceratosauria members

| style="background:#FEF6E4;" |

style="background:#FEF6E4;" |Grallator?

| style="background:#FEF6E4;" |

G.? isp.

| style="background:#FEF6E4;" |

Ifri N'Tfrane

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Theropod Tracks, referred usually to small-medium sized Genera

| style="background:#FEF6E4;" |

style="background:#FEF6E4;" |Hispanosauropus?

| style="background:#FEF6E4;" |

H.? isp.

| style="background:#FEF6E4;" |

Ifri N'Tfrane

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Theropod tracks of uncertain affinity, different from Megalosauripus in the larger metatarsophalangeal region

| style="background:#FEF6E4;" |

style="background:#FEF6E4;" |Megalosauripus{{Cite journal |last1=Hadri |first1=M. |last2=Lorente |first2=F. P. |date=2012 |title=Historia de yacimientos con huellas de dinosaurio, desde su descubrimiento hasta su primer estudio: alrededores de El Mers (Marruecos) |url=https://dialnet.unirioja.es/descarga/articulo/4118092.pdf |journal=Zubia |volume=30 |issue=6 |pages=93–147}}

| style="background:#FEF6E4;" |

M. ispp.
cf.M. ispp.

| style="background:#FEF6E4;" |

El Mers
Tasra
Tasra Westbank
Tassmante O'Moche
Oued Tamghilt

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Traces of theropods; members of the ichnofiber family Eubrontidae, incertae sedis within Theropoda

| style="background:#FEF6E4;" |

Averostra

Indeterminate

Oued Botane

|Isolated Teeth

|Isolated teeth of unidentified or undescribed/studied theropods. Teeth associated with the Teleosaur "Megalosaurus" mersensis have recently been suggesting to come from indeterminate Averostrans. Other remains need revision.{{Cite web |title=Non-theropods |url=https://theropoddatabase.github.io/Non-theropods.htm#Megalosaurusmersensis |access-date=2024-10-05 |website=theropoddatabase.github.io}}{{Cite web |title=Neotheropoda |url=https://theropoddatabase.github.io/Neotheropoda.htm#Averostra |access-date=2024-11-01 |website=theropoddatabase.github.io}}

style="background:#FEF6E4;" |Theropodipedia{{Cite journal |last1=Jenny |first1=Jacques |last2=Le Marrec |first2=Alain |last3=Monbaron |first3=Michel |date=1981 |title=Les empreintes de pas de Dinosauriens dans le Jurassique moyen du Haut Atlas central (Maroc): Nouveaux gisements et precisions stratigraphiques |url=http://dx.doi.org/10.1016/s0016-6995(81)80186-6 |journal=Geobios |volume=14 |issue=3 |pages=427–431 |doi=10.1016/s0016-6995(81)80186-6 |bibcode=1981Geobi..14..427J |issn=0016-6995}}

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Indeterminate

| style="background:#FEF6E4;" |

El Mers
Inzar O'Founass
Ifri N'Tfrane
Laach O'Medda
Oulad Ali
Tasra
Tasra Westbank
Tassmante O'Moche

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Theropod tracks of uncertain affinity, suggested to come from "allosaurs or megalosaurs"

| style="background:#FEF6E4;" |

== Sauropoda ==

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#FEF6E4;" |Breviparopus

| style="background:#FEF6E4;" |

B. isp.

| style="background:#FEF6E4;" |

El Mers
Oued Tamghilt

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Traces of sauropods typical of the ichnofamily Parabrontopodidae, incertae sedis within Sauropodomorpha. Includes traces with pes similar to Diplodocoidea.

| style="background:#FEF6E4;" |

style="background:#E6E6E6;" |

Cetiosaurus{{Cite journal|last1=Allain|first1=Ronan|last2=Aquesbi|first2=Najat|date=2008|title=Anatomy and phylogenetic relationships of Tazoudasaurus naimi (Dinosauria, Sauropoda) from the late Early Jurassic of Morocco |url=http://sciencepress.mnhn.fr/sites/default/files/articles/pdf/g2008n2a5.pdf |journal=Geodiversitas |volume=30 |issue=2 |pages=345–424}}

| style="background:#E6E6E6;" |

"C." mogrebiensis

| style="background:#E6E6E6;" |

Aîn ou N'Jourh
Taghrout
Tamguert r'Tane
Tamguert n'Tarit
Tich Niouine
Oued Botane

| style="background:#E6E6E6;" |

Complete skeleton and referred co-types of partially complete and incomplete specimens

| style="background:#E6E6E6;" |

A eusauropod of the family Cetiosauridae, currently awaiting revision and likely not a member of the genus Cetiosaurus{{Cite journal |last=Läng |first=E. |date=2008 |title=Les Cétiosaures (Dinosaura, sauropoda) et les sauropodes du Jurassique moyen: revision systématique, nouvelles découvertes et implications phylogénétiques |journal=(Doctoral dissertation, Paris, Muséum national d'histoire naturelle) |pages=1–223|s2cid=160327994 }}

| style="background:#E6E6E6;" |

Sauropoda{{Cite journal |last=Termier |first=Henri |date=1942-01-01 |title=Donnees nouvelles sur le Jurassique rouge a dinosauriens du Grand et du Moyen-Atlas (Maroc) |url=http://dx.doi.org/10.2113/gssgfbull.s5-xii.4-6.199 |journal=Bulletin de la Société Géologique de France |volume=S5-XII |issue=4–6 |pages=199–207 |doi=10.2113/gssgfbull.s5-xii.4-6.199 |issn=1777-5817}}{{Cite journal |last1=Charroud |first1=M. |last2=Fedan |first2=B. |date=1992 |title=Données préliminaires sur la découverte du gisement de Boulahfa à dinosauriens (SW de Boulemane, Moyen Atlas central) |url=https://naturalhistory.si.edu/sites/default/files/media/translated_publications/Charroud%26amp%3BFedan_92.pdf |journal=Notes et Mémoire du Service géologique du Maroc |volume=366 |issue=5 |pages=448–449}}

Indeterminate

Aït Tamjout
Boulahfa
1 km east of Taguelft

|Isolated and articulated bones

|Indeterminate or undescribed sauropod remains

style="background:#FEF6E4;" |Sauropodina{{Cite journal |last1=Meyer |first1=C. A. |last2=Thüring |first2=B. |date=2005 |title=Mind the Middle Jurassicgap-bone versus track record in dinosaurs |url=https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=a981e7967716fc9a9e1cb27c47ad5ca308a1efae |journal=Abstracts 3rd Swiss Geoscience Meeting Zurich |volume=3 |issue=1 |pages=59–60}}

| style="background:#FEF6E4;" |

Indeterminate

| style="background:#FEF6E4;" |

El Mers
Tasra
Tasra Westbank
Oulad Ali

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Sauropod tracks of uncertain affinity. There are both small and enormous sauropod tracks, including some among the largest known worldwide, with a pes track length of up to 130 cm.

| style="background:#FEF6E4;" |

== Ornithischia ==

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

Adratiklit{{Cite journal|last1=Maidment|first1=Susannah C.R.|last2=Raven|first2=Thomas J.|last3=Ouarhache|first3=Driss|last4=Barrett|first4=Paul M.|date=January 2020|title=North Africa's first stegosaur: Implications for Gondwanan thyreophoran dinosaur diversity|journal=Gondwana Research|volume=77|pages=82–97|doi=10.1016/j.gr.2019.07.007|bibcode=2020GondR..77...82M |doi-access=free|hdl=10141/622706|hdl-access=free}}

A. boulahfa

Boulahfa

|NHMUK PV R37366 (A dorsal vertebra), three cervical vertebrae (NHMUK PV R37367; R37368), a dorsal vertebra (NHMUK PV R37365), and a left humerus (NHMUK PV R37007)

|A dacentrurine stegosaur

|frameless

Cerapoda{{Cite journal |last1=Maidment |first1=Susannah |author-link1=Susannah Maidment |last2=Ouarhache |first2=Driss |last3=Butler |first3=Richard J |last4=Boumir |first4=Khadija |last5=Oussou |first5=Ahmed |last6=Ech-charay |first6=Kawtar |last7=El Khanchoufi |first7=Abdessalam |last8=Barrett |first8=Paul M |author-link8=Paul Barrett (palaeobiologist) |date=2025-03-12 |title=The world's oldest cerapodan ornithischian dinosaur from the Middle Jurassic of Morocco |journal=Royal Society Open Science |language=en |volume=12 |issue=3 |doi=10.1098/rsos.241624 |issn=2054-5703|pmc=11896692 }}

Indeterminate

Boulahfa

|USMBA 001, a partial left femur

|The oldest known cerapodan dinosaur

style="background:#FEF6E4;" |Ornithopodichnus?

| style="background:#FEF6E4;" |

O.? ispp.

| style="background:#FEF6E4;" |

Ifri N'Tfrane

| style="background:#FEF6E4;" |Footprints

| style="background:#FEF6E4;" |Ornithichian tracks, referred to short-toed forms such as Gilmoreosaurus

| style="background:#FEF6E4;" |

Spicomellus{{Cite journal|last1=Maidment|first1=Susannah C. R.|last2=Strachan|first2=Sarah J.|last3=Ouarhache|first3=Driss|last4=Scheyer|first4=Torsten M.|last5=Brown|first5=Emily E.|last6=Fernandez|first6=Vincent|last7=Johanson|first7=Zerina|last8=Raven|first8=Thomas J.|last9=Barrett|first9=Paul M.|date=2021-09-23|title=Bizarre dermal armour suggests the first African ankylosaur|url=https://www.nature.com/articles/s41559-021-01553-6|journal=Nature Ecology & Evolution|volume=5 |issue=12 |language=en|pages=1576–1581|doi=10.1038/s41559-021-01553-6|pmid=34556830 |bibcode=2021NatEE...5.1576M |s2cid=237616095 |issn=2397-334X}}

S. afer

Boulahfa

|NHMUK PV R37412, a partial rib bearing four co-ossified spines

|An early ankylosaurian

|frameless

Thyreosaurus{{Cite journal |last1=Zafaty |first1=O. |last2=Oukassou |first2=M. |last3=Riguetti |first3=F. |last4=((Company)) |first4=J. |last5=Bendrioua |first5=S. |last6=Tabuce |first6=R. |last7=Charrière |first7=A. |last8=Pereda-Suberbiola |first8=X. |date=2024 |title=A new stegosaurian dinosaur (Ornithischia: Thyreophora) with a remarkable dermal armour from the Middle Jurassic of North Africa |journal=Gondwana Research |volume=131 |pages=344–362 |issue=In press |doi=10.1016/j.gr.2024.03.009|bibcode=2024GondR.131..344Z }}

T. atlasicus

Boulahfa North

|HIIUC-BN00, a partial postcranial skeleton that includes nine dorsal vertebrae and 21 dorsal rib remains, a limb bone (fibula?), and six dermal elements

|A dacentrurine stegosaur with unusual recumbent osteoderms

|frameless

= Dasycladales =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#D1FFCF;" |Heteroporella

| style="background:#D1FFCF;" |

H. lusitanica

| style="background:#D1FFCF;" |

SW part of the Skoura syncline

| style="background:#D1FFCF;" |Calcareous imprints

| style="background:#D1FFCF;" |A dasycladacean algae of the family Dasycladaceae

| style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Sarfiatella

| style="background:#D1FFCF;" |

S. dubari

| style="background:#D1FFCF;" |

SW part of the Skoura syncline

| style="background:#D1FFCF;" |Calcareous imprints

| style="background:#D1FFCF;" |A dasycladacean algae, associated in adjacent regions with Aalenian–Bajocian faunas

| style="background:#D1FFCF;" |

= Charophyta =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#D1FFCF;" |Porochara

| style="background:#D1FFCF;" |

P. hians

| style="background:#D1FFCF;" |

Ait Hammou

| style="background:#D1FFCF;" |Oogonia

| style="background:#D1FFCF;" |A characean algae of the family Porocharaceae; charophytes are abundant in lower levels, associated with freshwater ostracods

| style="background:#D1FFCF;" |File:CharaFragilis.jpg

= Plantae =

class="wikitable"

!Genus

!Species

!Stratigraphic position

!Material

!Notes

!Images

style="background:#D1FFCF;" |Araucariacites

|style="background:#D1FFCF;" |

A. australis

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Pollen

|style="background:#D1FFCF;" |Affinities with Araucariaceae inside Coniferae.

| rowspan="2" style="background:#D1FFCF;" |File:Araucaria cunninghamii cones.jpg cones]]

style="background:#D1FFCF;" |Callialasporites

|style="background:#D1FFCF;" |

C. dampieri
C. segmentatus
C. turbatus
C. spp.

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Pollen

|style="background:#D1FFCF;" |Affinities with Araucariaceae inside Coniferae.

style="background:#D1FFCF;" |Classopollis

|style="background:#D1FFCF;" |

C. (Corollina) spp.

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Pollen

|style="background:#D1FFCF;" |Affinities with Cheirolepidiaceae inside Coniferae.

|style="background:#D1FFCF;" |

style="background:#D1FFCF;" |Cyathidites

|style="background:#D1FFCF;" |

C. ssp.

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Spores

|style="background:#D1FFCF;" |Affinities with the family Cyatheaceae inside Cyatheales. Arboreal Fern Spores

|style="background:#D1FFCF;" |File:Cyathea arborea.JPG, Cyathidites come probably from similar genera]]

style="background:#D1FFCF;" |Densoisporites

|style="background:#D1FFCF;" |

D. spp.

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Spores

|style="background:#D1FFCF;" |Affinities with the Selaginellaceae in the Lycopsida.

|style="background:#D1FFCF;" |File:Selaginella_erythropus_kz02.jpg. Densoisporites probably come from a similar Plant]]

style="background:#D1FFCF;" |Lycopodiumsporites

|style="background:#D1FFCF;" |

L. austroclavatidites
L. spp.

|style="background:#D1FFCF;" |

FD section, Skoura Syncline

|style="background:#D1FFCF;" |Spores

|style="background:#D1FFCF;" |Affinities with the family Lycopodiaceae in the Lycopodiopsida. Lycopod spores, related to herbaceous flora common in humid environments.

|style="background:#D1FFCF;" |File:Lycopodium_annotinum_161102.jpg. Lycopodiumsporites probably come from a similar plant]]

style="background:#D1FFCF;" |Protocupressinoxylon{{Cite journal |last1=Philippe |first1=M. |last2=Bamford |first2=M. |last3=McLoughlin |first3=S. |last4=Alves |first4=L.S.R. |last5=Falcon-Lang |first5=H.J. |last6=Gnaedinger |first6=S. |last7=Ottone |first7=E.G. |last8=Pole |first8=M. |last9=Rajanikanth |first9=A. |last10=Shoemaker |first10=R.E. |last11=Torres |first11=T. |last12=Zamuner |first12=A. |date=2004 |title=Biogeographic analysis of Jurassic–Early Cretaceous wood assemblages from Gondwana |url=http://dx.doi.org/10.1016/j.revpalbo.2004.01.005 |journal=Review of Palaeobotany and Palynology |volume=129 |issue=3 |pages=141–173 |doi=10.1016/j.revpalbo.2004.01.005 |bibcode=2004RPaPa.129..141P |issn=0034-6667}}

| style="background:#D1FFCF;" |