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> Subject: "Lizzie"
> Can anyone tell me about the characteristics of "Lizzie,"
> earliest reported reptile fossil, that distinguish it from other coeval
> tetrapods? "Lizzie" was found in the Early Carboniferous
> to North Americans) in East Kirkton, Scotland.
Don suggested that the rest of the group may like to read the abstract
from Tim Smithson's paper in the Transactions of the Royal Society of
Edinburgh Vol. 84 pp383-412.
'*Westlothiana lizzae* is known from the Brigantian of East Kirkton,
Scotland. The skull resembles that of later amniotes in the large size
of the paietal, the apparent loss of the intertemporal, and the absence
of a squamosal notch, palatal fangs and labyrinthine infolding of the
marginal teeth, but is primitive in the absence of a transverse flange
of the pterygoid. The individual trunk vertebrae resemble those of
amniotes; large intercentra are retained, but the neural arch is fused
to the centrum. A surprising feature is the presence of 36 presacral
vertebrae, as is the relative size of the very small but highly ossified
limbs. The humerus is much shorter than the femur, but similar in
configuration to that of early amniotes. There are three proximal
tarsals as in primitive tetrapods, but an amniote phalangeal count.
The presence of massive dorsal as well as ventral scales is a more
primitive feature than that of most anthracosaurs.
*Westlothiana* is 'reptiliomorph', and is judged to ba a stem-group
amniote on features of the skull roof, the absence of an otic notch, the
gastrocentrous vertebrae and the pedal phalangeal formula. It has
not, however, reached the amniote condition in the structure of the
tarsus, and the palate is more primitive than that of both early
amniotes and 'diadectomorphs'.
The other 'reptiliomorph' from East Kirkton is *Eldeceeon rolfei*
(named after LDC [Livingston Development Corporation] who helped
purchase the specimen for the museum in Edinburgh).
Curator of Palaeontology
University of Glasgow
The first law of Geology is the law of supposition.
(Geological Howlers - ed. WDI Rolfe)