Baraposaurus tagorei
Toarcian of Gondwanaland
illustration by Steve Kirk - Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals
More on Barapasaurus
Vulcanodon karibaensis Raath 1972
Vulcanodon beds, Mashonaland North, Zimbabwe
Partial skeleton 6 meters long, missing neck and
head
Estimated total length around 8 metres; Weight several
tonnes
Lifestyle: Very large terrestrial herbivore
Age: Sinemurian
Vulcanodon is the most primitive known sauropod dinosaur, and retains a number of prosauropod features. Yet some of the characteristics of the skeleton, such as the pubis, are anatomically more advanced than in larger and later sauropods like Barapasaurus. This is a good example of what is called "mosaic" evolution, the presence of both primitive and advanced characteristics within transitional organisms (Archaeopteryx is a good example of this, displaying both theropod ("prmitive") and bird ('advanced") characteristics.)
Somewhat contradictory dates have been given for the "Vulcanodon Beds". Although reported from the earliest Jurassic, close to the Triassic boundary (i.e. early Hettangian), pollen analysis indicates a date no older than the Sinemurian, and possibly younger [Paul E. Olsen & H-D Sues, "The Triassic-Jurassic tetrapod transition", p.329 n.; in The Beginning of the Age of Dinosaurs, ed. K.Padian]. I have tentatively dated Vulcanodon as Sinemurian. In any case it seems that the Vulcanodontids and their descendents quickly supplanted the Plateosaurs as large terrestrial herbivores, althogh smaller prosauropods continued up until the Toarcian.
Kunmingosaurus wudingensis Zhao, 1985
nearly complete skeleton
Overall length: 6 metres
Chinshakiangosaurus zhongheensis Yeh, 1975
fragmentary skeleton
Overall length: ?12 - ?13 metres
Reference is made to a sauropod dinosaur from the Wudin basin
in Yunnan, China. Although the horizon is thought equivalent to the
adjacent famous prosauropod-dominated Lower Lufeng formation (Hettangian),
there is no evidence for sauropods in the Lufeng beds [A.L.Sun and K.H.Cui,
"The Lower Lufeng Saurischian fauna", p.278, and Peter M. Galton, "Herbivorous
adaptions of dinosaurs, p.208; in The Beginning of the Age of Dinosaurs,
ed. K.Padian] and it is likely that Kunmingosaurus and Chinshakiangosaurus
comes from a later period, perhaps close in time to Vulcanodon.
A Sinemurian
age is tentatively suggested. (The Dinosauricon entry for 
Chinshakiangosaurus
has the date as late Jurassic, but this is most probably an error.)
Damalosaurus spp. Zhao 1983
Yet another brief reference to a far-east Asian early Jurassic
sauropod, this one from Tibet [Peter M. Galton, "Herbivorous adaptions
of dinosaurs, p.208; in The Beginning of the Age of Dinosaurs, ed.
K.Padian]. As the Sinemurian
Scelidosaurus also has been supposedly reported from Tibet
[unfortunately my only reference here is David Lambert's Field Guide
to Dinosaurs], these two may possibly have been contemporary.
Mike Keesey [Damalasaurus
page] gives the age as Middle Jurassic, the locality as China
(tsk tsk!), and suggests this genus may possibly be a Brachiosaur.
Of course it might also be a distinct lineage of primitive sauropod.
D. laticostalis Zhao, 1985
D. magnus
Both these species are now considered invalid [nomen
nudum].
Zizhongosaurus chuanchengensis Dong, Zhou, and Zhang 1983
Da'znzhai Formation, Sichuan, China
Some post-crania
estimated length: 9 meters
references:
The Dinosauria, p.78
Zizhongosaurus
page [Dinosauricon]
Ohmdenosaurus liasicus Wild, 1978
Posidonienschiefer, Baden-Wurttemberg, Germany
Age: Middle Toarcian
Limb bone
Estimated overall length: 4 metres
This very small, primitive sauropod is known only from a single
limb bone, once thought to belong to a plesiosaur.
Although classified under the family Vulcanodontidae it may instead belong
to a distinct group, which might be called family Ohmdenosauridae.
It had no clear descendents, and may have been one of the many types of
dinosaur that were wiped out by the terminal Toarcian extinction event.
Øyvind
M. Padron)Barapasaurus tagorei Jain, Kutty, Roy-Chowdhury, & Chatterjee,
1975
Kota Formation, Andhra Pradesh, India
Length: 14.5 to 18 metres; Weight: 13 to
25 tonnes
Remains of 6 partial skeletons (missing skull & feet)
Toarcian
The first of the really big sauropods, Baraposaurus equalled in size the giants of the later Jurassic. In structure however it was much more primitive, resembling Vulcanodon in many features of the skeleton. As befits its transitional nature, it is sometimes included under the Vulcanodontidae, sometimes under the Cetiosauridae, and sometimes in its own family. Barapasaurus is another example of "mosaic evolution" among transitional forms. According to the Argentine palaeontologist Jose Bonaparte the dorsal vertebrae of Barapasaurus are of the standard Cetiosaur grade, with a tall neural arch and zygapophyses far above the neural canal; much more advanced the vertebrae of Vulcanodon.
references:
Jose
Bonaparte, 1986, "The early radiation and phylogenetic relationships of
the Jurassic sauropod dinosaurs, based on vertebral anatomy", in The
Beginning of the Age of Dinosaurs, ed. K.Padian]
Kotasaurus yamanpalliensis Yadagiri, 1988
Kota Formation, Andhra Pradesh, India
Length: 6 metres
partial skeletons
Toarcian
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