Friday, December 18, 2015

The Giving of December. Lapparentosaurus

  The type fossil material was originally assigned to the sauropod genus Bothriospondylus.‭ ‬However,‭ ‬not only is Bothriospondylus considered a dubious genus of sauropod because of the lack of identifiable features upon the type material,‭ ‬but the type material came from England,‭ ‬a long way from Madagascar.‭ ‬For this reason the palaeontologist Jose Bonaparte renamed the Madagascan material as a new genus‭; ‬Lapparentosaurus.
       Lapparentosaurus is represented by several individuals,‭ ‬though the exact number is hard to determine.‭ ‬However,‭ ‬the individuals that do represent Lapparentosaurus are of different growth stages,‭ ‬allowing‭ ‬palaeontologists to get an idea of how Lapparentosaurus grew to adulthood.‭ ‬There is some uncertainty about whether Lapparentosaurus was a primitive member of the macronarian sauropods or a distinct brachiosaurid.‭ ‬Cladistic analysis has supported the idea Lapparentosaurus was a primitive macronarian,‭ ‬and this also ties in to the appearance of Lapparentosaurus in the Bathonian stage of the Jurassic,‭ ‬roughly where we would expect primitive macronarian sauropods to be.‭ ‬Brachiosaurids however,‭ ‬while still classed as macronarians themselves,‭ ‬are more advanced in form and do not become common until the late Jurassic‭ (‬going by brachiosaurid fossil appearances in the fossil record‭)‬.

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