> Since recent psittacosaur discoveries include skeletons
associated with gastroliths, it is also
> suggested that they may have been omnivorous.
Well, described in 1924 is kind of recent :-) . Who
suggested lithophagy was associated with omnivory?
During their May-June 2001 expedition to
Inner-Mongolia, Sereno and his team also reported a psittacosaur specimen
associated with gastroliths.
> On the other hand, there are several other dinosaur
genera that have remains associated with
> gastroliths;
Syntarsus, Poekilopleuron and Lourinhanosaurus (the
allosauroid, not Lourinhasaurus the camarasaurid) have been found with
gastroliths. In fact, a wide range of animals are known to be
lithophagous, including obviously carnivorous species like Protorosaurus and
certain snakes.
You're correct in pointing out that it's the
allosauroid Lourinhanosaurus that was associated with gastroliths, when I
launched a query in my dinosaur database, the record popped up right
below Dinheirosaurus (I had sauropods on my mind at that moment and
misread it). Together with the 2 other theropod taxa you mention, it seems
like gastroliths are now well represented in the theropod fossil record; from
the coelophysid Syntarsus, megalosaur Poekilopleuron, allosauroid
Lourinhanosaurus, to ornithomimosaurs and the advanced maniraptoran
Caudipteryx (and extant Neornithes).
Regards,
Gunter Van
Acker