Re: "Lizzie"

[NEIL CLARK <NCLARK@museum.gla.ac.uk>]

> Subject:       "Lizzie"

> Greetings,
>       Can anyone tell me about the characteristics of "Lizzie,"  
the
> earliest reported reptile fossil, that distinguish it from other coeval
> tetrapods?  "Lizzie" was found in the Early Carboniferous 
(Mississippian
> 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).


Neil Clark
Curator of Palaeontology
Hunterian Museum
University of Glasgow
email: NCLARK@museum.gla.ac.uk

The first law of Geology is the law of supposition.
(Geological Howlers - ed. WDI Rolfe)