Juravenator

Name: Juravenator ‭(‬Jura hunter‭)‬.
Phonetic: Jooh-ah-ven-ah-tor.
Named By: Göhlich‭ & ‬Chiappe‭ ‬-‭ ‬2006.
Classification: Chordata,‭ ‬Reptilia,‭ ‬Dinosauria,‭ ‬Saurischia,‭ ‬Coelurosauria,‭ ‬Compsognathidae.
Species: J.‭ ‬starki‭ (‬type‭)‬.
Diet: Carnivore/Insectivore.
Size: 70‭ ‬centimetres long.
Known locations: Germany,‭ ‬Jura‭ ‬Mountains.
Time period: Kimmeridgian of the Jurassic.
Fossil representation: Single specimen of a juvenile,‭ ‬and a skin impression.

       Juravenator was a small predatory dinosaur active‭ ‬in‭ ‬the late Jurassic of Europe.‭ ‬It appears to have been a fleet footed hunter that specialised in either invertebrates or small vertebrates like lizards.‭ ‬The scleral rings of Juravenator show similarities with nocturnal birds strongly suggesting that Juravenator was most active at night.
       The holotype specimen of Juravenator was assumed to have a covering of primitive protofeathers,‭ ‬something that gave rise to the nickname Borsti‭ (‬after bristle haired dogs‭)‬.‭ ‬However when skin impressions belonging to Juravenator were initially described they were found to have no clear indication of protofeathers just scales.‭ ‬This is markedly different from other members of the Compsognathidae such as Sinosauropteryx which are known to have had them.‭ ‬Other longer known members of the group such as Compsognathus neither confirm or deny the presence of feathers,‭ ‬but Compsognathus itself is morphologically similar to the‭ ‘‬dino-bird‭’ ‬Archaeopteryx in its skeletal make up.‭ ‬This means that the Compsognathidae group may either end up being re-shuffled into feathered and non-feathered,‭ ‬or it should be accepted that small dinosaurs being feathered is not a hard and fast rule that can be applied to all genera.‭
       Of course further fossil discoveries may yet reveal a completely different realisation,‭ ‬and a follow up study in‭ ‬2010‭ ‬by Xu Xing reported that when viewed under Ultraviolet light a light covering of protofeathers are visible.‭ ‬It‭’‬s possible that as a juvenile its covering of feathers was not fully developed.‭ ‬However it is also possible that Juravenator had protofeathers upon hatching which then disappeared when it grew older.‭ ‬Alternatively the type specimen may have been in a moult when it died resulting in the appearance of reduced feathers for the living animal.

Further reading
- A new carnivorous dinosaur from the Late Jurassic Solnhofen archipelago. - Nature 440:329-332. - U. B. Göhlich & L. M. Chiappe - 2006.
- Juravenator starki (Reptilia, Theropoda) ein neuer Raubdinosaurier aus dem Oberjura der Suedlichen Frankenalb (Sueddeutschland): Skelettanatomie und Weichteilbefunde. - Archaeopteryx 24: 1–26. - U. B. Goehlich, H. Tischlinger & L. M. Chiappe - 2006.
- Anatomy of Juravenator starki (Theropoda: Coelurosauria) from the Late Jurassic of Germany. - Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 258 (3): 257–296. - L. M. Chiappe & U. B. Göhlich - 2010.
- Re-evaluating Moodie's Opisthotonic-Posture Hypothesis in fossil vertebrates. Part I: Reptiles - The taphonomy of the bipedal dinosaurs Compsognathus longipes and Juravenator starki from the Solnhofen Archipelago (Jurassic, Germany). - Palaeobiodiversity and Palaeoenvironments 92 (1): 119–168. - A. G. Reisdorf & M. Wuttke - 2012.



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