Lesothosaurus

Name: Lesothosaurus ‭(‬Lesotho lizard‭)‬.
Phonetic: Leh-so-foe-sore-us.
Named By: Peter M.‭ ‬Galton‭ ‬-‭ ‬1978.
Synonyms: Stormbergia‭?
Classification: Chordata,‭ ‬Reptilia,‭ ‬Dinosauria,‭ ‬Ornithischia,‭ ‬Genasauria,‭ ‬Lesothosauridae.
Species: L.‭ ‬diagnosticus‭ (‬type‭)‬.
Diet: Herbivore.
Size: About‭ ‬1‭ ‬meter long.
Known locations: South Africa‭ ‬-‭ ‬Upper Elliot Formation.
Time period: Hettangian/Sinemurian of the Jurassic.
Fossil representation: Remains of several individuals.‭

       Although only a very small dinosaur,‭ ‬Lesothosaurus has raised a lot of questions as to exactly what it was and how the genus was related to other ornithischian dinosaurs.‭ ‬When first described by Galton in‭ ‬1978,‭ ‬Lesothosaurus was proposed to be an ornithopod.‭ ‬However the genus has also been considered to be a very primitive member or the ornithischia,‭ ‬a primitive neornithischian as well as a very primitive thyreophoran‭ (‬the group that stegosaurian and ankylosaurian dinosaurs stem from‭)‬.‭
       Lesothosaurus has also been considered to be a synonym to the genus‭ ‬Fabrosaurus that was named earlier in‭ ‬1964.‭ ‬However,‭ ‬since Fabrosaurus was based upon the description of a jawbone and three teeth,‭ ‬it has been extremely hard to establish this with certainty.‭ ‬Another genus called Stormbergia that was named in‭ ‬2005‭ ‬has also been speculated to be the fully grown form of Lesothosaurus.‭ ‬If true then Stormbergia would actually be a synonym to Lesothosaurus.
       In terms of being a living dinosaur,‭ ‬Lesothosaurus had rear legs that were very long in proportion to their body size,‭ ‬something that leads to the assumption that Lesothosaurus relied upon small size,‭ ‬speed and agility to evade predators such as larger theropod dinosaurs of the saurischian line.‭ ‬The fore limbs were short by comparison to the legs and with small hands,‭ ‬however each hand possessed five fingers,‭ ‬four of which were well developed.
       In life Lesothosaurus would have had a keratinous beak formed on the anterior of the upper and lower jaws,‭ ‬and this would have been of use for snipping off plant parts.‭ ‬Within the mouth there were two kinds of teeth,‭ ‬twelve fang-like one in the upper jaw,‭ ‬and leaf-shaped shearing teeth behind them and in the lower jaw.‭ ‬It would be the combination of the horny beak and the up/down shearing action of the teeth which would have been the main food processing areas before food was swallowed.

Further reading
-‭ ‬Fabrosauridae,‭ ‬the basal family of ornithischian dinosaurs‭ (‬Reptilia:‭ ‬Ornithischia‭) ‬-‭ ‬Paläontologische Zeitschrift‭ ‬52‭(‬1/2‭)‬:138-159‭ ‬-‭ ‬Peter M.‭ ‬Galton‭ ‬-‭ ‬1978.
-‭ ‬The‭ '‬fabrosaurid‭' ‬ornithischian dinosaurs of the Upper Elliot Formation‭ (‬Lower Jurassic‭) ‬of South Africa and Lesotho‭ ‬-‭ ‬Zoological Journal of the Linnean Society‭ ‬145:‭ ‬175-218‭ ‬-‭ ‬R.‭ ‬J.‭ ‬Butler‭ ‬-‭ ‬2005.
-‭ ‬Ontogenetic change and adult body size of the early ornithischian dinosaur Lesothosaurus diagnosticus:‭ ‬implications for basal ornithischian taxonomy‭ ‬-‭ ‬Gondwana Research.‭ ‬online‭ ‬17‭ (‬1‭)‬:‭ ‬171‭ ‬-‭ ‬F.‭ ‬Knoll,‭ ‬K.‭ ‬Padian‭ & ‬A.‭ ‬de Ricqles‭ ‬-‭ ‬2009.



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