Re: Abelisaur & Titanosaur migratory routes

[Thomas_R_HOLTZ@umail.umd.edu (th81)]

>In the lastest issue of The Dinosaur Report (Fall 1995) the article "The 
>Last Dinosaurs of India" by Sankar Chatterjee illustrates the migration 
>route of abelisaurs & titanosaurs from South America to India during the 
>Late Cretaceous.
>
Dammit!  I don't have this yet, either!  First, no most-recent-issue of JVP,
now this.  Grrr.

>The route illustrated (p.15, fig.3): South America to North America 
>(western half) to Asia via. Beringia to India and finally India to 
>eastern Africa to France.
>
>This doesn't seem right...
>1) No Abelisaur or Titanosaurs have been found in the northern parts of 
>North America and Asia with any certainity.

True, although Opisthocoeliacaudia seems to be from a linneage which is the
sister taxon to Titanosauria.

>2) Assumption made that Abelisaurs & Titanosaurs originated in South 
>America.

Which may be false, as you note.
>
>Alternative view...
>1) Titanosaurs originiated in Africa (lastest Jurassic or early Cretaceous) 
>and radiated to Europe, South America, and India via Madagascar.  The 
>titanosaur (Alamosaurus) invaded western North America (as far north as 
>Utah) via South America.

Titanosaurs are known from the Late Jurassic of Africa (& the Early & Late K
of Africa, for that matter).

>2) Abelisaurs originated in Europe and radiated to Africa then to South 
>America and India.
>
The oldest known abelisaurids, Carnotaurus and the unnamed abelisaur
recently found by Russell, are mid-K (Albian) age.

>Questions:
>1) When did Africa & South America become completely seperated?
>
Hard to say.  Many biogeographic reconstuctions show a Brazil-west Africa
connection into the Cenomanian.

>2) Is Titanosaurus falloti Hoffet, 1942 really a titanosaur or is it 
>something else?

Buffetaut thinks it is something else.
>
>3) Dravidosaurus blanfordi was recently determined to be a plesiosaur.
>What is the status of Brachypodosaurus gravis & Lametasaurus indicus (the
>non-theropod parts)? 

mmmm.  Maybe George or Tracy Ford have some insight into these.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist
Dept. of Geology
University of Maryland
College Park, MD  20742
Email:Thomas_R_HOLTZ@umail.umd.edu (th81)
Fax: 301-314-9661
Phone:301-405-4084