''Adratiklit'' (meaning "mountain lizard") is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

stegosauria Stegosauria is a group of herbivorous ornithischian dinosaurs that lived during the Jurassic and early Cretaceous periods. Stegosaurian fossils have been found mostly in the Northern Hemisphere, predominantly in what is now North America, Euro ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

that lived on the supercontinent

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final st ...

during the

Middle Jurassic The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations ...

period (168–164 million years ago). The genus contains a single species, ''Adratiklit boulahfa''. Its remains were found in the

El Mers Group The El Mers Group is a geological group in the Middle Atlas of Morocco. It is subdivided into 3 formations named the El Mers 1, 2 and 3 Formations respectively. It is a marine deposit primarily consisting of marl, with gypsum present in the upper ...

, probably in the El Mers II Formation (

Bathonian In the geologic timescale the Bathonian is an age and stage of the Middle Jurassic. It lasted from approximately 168.3 Ma to around 166.1 Ma (million years ago). The Bathonian Age succeeds the Bajocian Age and precedes the Callovian Age. St ...

), near Boulahfa, south of Boulemane, Fès-Meknes, north

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria ...

Eurypoda Thyreophora ("shield bearers", often known simply as "armored dinosaurs") is a group of armored ornithischian dinosaurs that lived from the Early Jurassic until the end of the Cretaceous. Thyreophorans are characterized by the presence of body ...

n dinosaurs, in particular stegosaurs, were diverse and abundant in

Laurasia Laurasia () was the more northern of two large landmasses that formed part of the Pangaea supercontinent from around ( Mya), the other being Gondwana. It separated from Gondwana (beginning in the late Triassic period) during the breakup of Pan ...

(nowadays the northern continents) during the Jurassic, but their remains are extremely rare in deposits of Gondwana, (nowadays the southern continents). Nevertheless, the existence of fragmentary remains and trackways in the deposits of Gondwana indicate the presence of eurypodan taxa there. ''Adratiklit'' is the first described eurypodan taxon from

North Africa North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in t ...

, as well as the second oldest known stegosaur (being slightly younger than ''

Bashanosaurus ''Bashanosaurus'' (meaning "Bashan lizard", after an ancient name for Chongqing) is a genus of stegosaur dinosaur recovered from the Bajocian (Middle Jurassic)-aged Shaximiao Formation of Yunyang, Chongqing, China. The type species is ''Bashan ...

''), with the possible exception of ''

Isaberrysaura ''Isaberrysaura'' is a genus of stegosaurian ornithischian dinosaur from the Middle Jurassic Los Molles Formation of Patagonia, Argentina. The genus contains a single species, ''I. mollensis'', described by Salgado ''et al.'' in 2017 from a sin ...

'' and "

Ferganastegos This list of informally named dinosaurs is a listing of dinosaurs (excluding Aves; birds and their extinct relatives) that have never been given formally published scientific names. This list only includes names that were not properly published ...

",Ulansky, R. E., (2014). Evolution of the stegosaurs (Dinosauria; Ornithischia). Dinologia, 35 pp.

n Russian N, or n, is the fourteenth letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''en'' (pronounced ), plural ''ens''. History ...

OWNLOAD PDFttp://dinoweb.narod.ru/Ulansky_2014_Stegosaurs_evolution.pdf. which may be as old as ''Adratiklit''.

Discovery and naming

''Adratiklit boulahfa'' was described by Susannah C.R. Maidment, Thomas J. Raven, Driss Ouarhache and Paul M. Barrett on 16 August 2019 in an article published online in paleontological journal ''

Gondwana Research ''Gondwana Research'' is a peer-reviewed scientific journal with an "all earth science" scope and an emphasis on the origin and evolution of continents. It is part of the Elsevier Elsevier () is a Dutch academic publishing company speciali ...

''; the article was published physically in January 2020. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

of ''Adratiklit boulahfa'' is a dorsal vertebra,

NHMUK The Natural History Museum in London is a museum that exhibits a vast range of specimens from various segments of natural history. It is one of three major museums on Exhibition Road in South Kensington, the others being the Science Museum (Lo ...

PV R37366. Referred specimens include three cervical vertebrae (NHMUK PV R37367 and NHMUK R37368, the latter specimen consisting of a series of two articulated bones), a dorsal vertebra (NHMUK PV R37365) and a left humerus (NHMUK PV R37007). The specimens were acquired by the Natural History Museum in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

from fossil traders. They represent multiple individuals, probably five. While the second dorsal vertebra shares traits with the holotype, the other referrals are merely based on the fact that the material is stegosaurian. An attempt in 2018 to locate the site did not produce any relevant fossils but led to a deeper insight into the geology. The generic name ''Adratiklit'' is derived from the

Berber Berber or Berbers may refer to: Ethnic group * Berbers, an ethnic group native to Northern Africa * Berber languages, a family of Afro-Asiatic languages Places * Berber, Sudan, a town on the Nile People with the surname * Ady Berber (1913–1 ...

words "adrar", meaning "mountain", and "tiklit", meaning lizard. The specific name, ''boulahfa'', refers to the area of Boulahfa near where the specimen was said to be found.

Description

While the holotype for ''Adratiklit'' only includes a dorsal vertebra, a few other remains are known, including an upper arm bone and additional vertebrae. The fossilized humerus is long. The describers established two

autapomorphies In phylogenetics, an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa, not even those most closely related to t ...

, or unique derived traits. With the dorsal vertebrae, the

prezygapophysis The articular processes or zygapophyses ( Greek ζυγον = " yoke" (because it links two vertebrae) + απο = "away" + φυσις = " process") of a vertebra are projections of the vertebra that serve the purpose of fitting with an adjacent ver ...

has a small triangular rough protrusion on top, behind the front articulation facet of the vertebral body. With the dorsal vertebrae, the centroparapophysal laminae being drawn on the anteriorly-projecting rugosities that are located on either side of the neural canal in dorsal vertebrae, the ridges between the vertebral body and the parapophyses, the contact facets for the lower rib heads, end in rough areas protruding to the front on both sides of the front opening of the

neural canal In the developing chordate (including vertebrates), the neural tube is the embryonic precursor to the central nervous system, which is made up of the brain and spinal cord. The neural groove gradually deepens as the neural fold become elevated, a ...

. These traits are unique for the Stegosauria as a whole and are diagnostic to this taxa. The size of ''Adratiklit'' is not known due to a lack of fossil remains.

Classification

''Adratiklit'' is a basal

n. It is more closely related to the European stegosaurs ''

Dacentrurus ''Dacentrurus'' (meaning "tail full of points"), originally known as ''Omosaurus'', is a genus of stegosaurian dinosaur from the Late Jurassic to Early Cretaceous (154 - 140 mya) of Europe. Its type species, ''Omosaurus armatus'', was named in 1 ...

'' and ''

Miragaia Miragaia () is a former civil parish in the municipality of Porto, Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwe ...

'' than it is to the southern African taxa ''

Kentrosaurus ''Kentrosaurus'' ( ; ) is a genus of stegosaurid dinosaur from the Late Jurassic in Lindi Region of Tanzania. The type species is ''K. aethiopicus'', named and described by German palaeontologist Edwin Hennig in 1915. Often thought to be a "pri ...

'' and ''

Paranthodon ''Paranthodon'' ( ) is a genus of stegosaurian dinosaur that lived in what is now South Africa during the Early Cretaceous, between 139 and 131 million years ago. Discovered in 1845, it was one of the first stegosaurians found. Its only rem ...

''.

References

{{Taxonbar, from=Q66553039 Middle Jurassic dinosaurs of Africa Stegosaurs Fossil taxa described in 2019 Ornithischian genera

Discovery and naming

Description

Classification

See also

References