Name: Keichousaurus hui
Age: Lower Triassic, Spathian Stage (~242 m.y.a.)
Size: (25.4 mm = 1 inch): 202 mm long (tip of skull to tip of tail along backbone) Matrix: 235 mm by 116 mm
Location: Huxia Formation, Guanglin, Guizhou Proovince of China
Code: KH004
Price: $725.00 - Sold
 Description:
This is a fine example of a semiaquatic reptile from the Triassic
of China known as Keichousaurus hui. The Keichosaurs were members
of the Pachypleurisauridae, and as such were related to their contemporaries
the Nothosaurs (indeed, at one point they were referred to the Nothosauridae).
They are thought to have been a bridge between the Placodonts and
the later Plesiosaurs. The genus derives its name from the 1957 location
in Keichow Province where they were first discovered. With a maximum
size of ~ 300 mm, this one is an adult. The Keichousaurs were thought
to be able to make their way on land by virtue of their strong limbs
(note the robust ulna). Some believe they lived in a marshy environment.
The Pachypleurosaurs are believed to have evolved in China, making
their way to Europe via the northern border of the Tethys Sea. None
of the later European members of the family had the massive limb bones
seen in Keichousaurus. There are actually two morphotypes known, a
robust and a gracile one, presumably an expression of sexual dimorphism.
Two recently described specimens of the gracile type were found to
have several embryos inside. Based upon their positions within the
adult and their orientation, they were indubitably embryos being carried
by the mother. As a consequence, the ones with the more robust forelimbs
are presumed to be males (see my other offerings for a fine example).
This specimen is shown in dorsal aspect. Unlike many offered, this
one is quite 3_D, without the flattened bones often due to preparation
with a wire brush. Notice the fine details to the skull, including
the teeth. |
