Re: Richardostesia teeth

[Michael Mortimer <mickey_mortimer111@msn.com>]

Jaime A. Headden wrote-

> Michael Mortimer (mickey_mortimer111@msn.com) wrote:
>
> <Because they both have very tiny serrations.  So does Nuthetes, which I
> believe falls into the range of Richardoestesia morphotypes.>
>
>   It is not so much the size of the serrae as the shape of the serrae, 
> being
> low, and nearly quandrangular, along with size distribution along the 
> carinae.
> The shapes oft he teeth are also very coincident, with all teeth attributed 
> to
> this genus being relatively straight with minimal recurvature. The *R.
> isoceles* teeth are just less recurved and in fact less recumbent than the
> teeth attributed to *R. gilmorei*.

Denticle shape is not uniform/distinct in the genus, as noted by Sankey et 
al. (2002) for R. gilmorei- "Denticle tips can be slightly pointed, rounded, 
or flattened."  While she describes R. isosceles as- "Denticle tips are 
straight or slightly rounded, but not pointed."
Similarly, all teeth referred to Richardoestesia are not relatively 
straight.  Again, describing R. gilmorei- "Isolated teeth vary in curvature 
from almost completely straight (0.1 mm curvature) to strongly recurved (0.7 
mm curvature)."
The denticle size distribution along the carinae for R. gilmorei ("Denticle 
size varies slightly along the carinae, with smaller ones at the base and 
tip.") is not distinct from Saurornitholestes ("Denticle size varies along 
the carina, they tend to be smaller at the base and tip of teeth.").  R. 
isosceles has a different size distribution though- "Posterior denticles are 
... uniformly-sized along tooth,"

Indeed, Sankey later states "Richardoestesia isosceles is included in the 
genus Richardoestesia
because of the presence of small denticles. However, the shape of the 
denticles in Richardoestesia gilmorei and isosceles is different."

Mickey Mortimer