Andesaurus new version

This is a revised version of my Andesaurus skeletal. This is a more rigorous version, with both pairs of limbs shown, an elevated neck, as well as some changes to the (unknown) sternal plates and ribs.

Also, here's the spiel I said about this animal last time:

Andesaurus delgadoi is a poorly known titanosaur sauropod from the Mid-Cretaceous (Albian-Cenomanian) of the Rio Limay Formation in Neuquen Province, Argentina.

Often considered one of the largest dinosaurs in the 60+ tonne range and around 25-30 meters long, a re-description of the specimen by Mannion and Calvo (2011) shows that it was quite a bit smaller than often thought. As restored here, it is about 16 (~52 ft) meters long from the tip of the skull to the end of the tail and probably would have massed about 8-19 tonnes. The mass estimate is much more approximate than for, say, Malawisaurus due to the fragmentary nature of its remains.

The preserved remains include 25 partial to complete caudal (tail) vertebrae, 2 sacral vertebrae, 4 posterior dorsal vertebrae (only 3 of which are complete enough to illustrate), a partial femur and a partial humerus, as well as a pubis and ischium, and some metacarpals.

The rest of the skeletal reconstruction is based primarily on Huabeisaurus due to the extreme similarity of the overlapping remains between it and Andesaurus. Parts of Huabeisaurus that were used for comparison were the nature of dorsal and caudal vertebrae, as well as the pelvic elements. The restored ilium (hip bone), scapula, cervical vertebrae and anterior caudal neural spines were all drawn directly from the description of Huabeisaurus. In the case of the anterior caudal neural spines (which are missing from the first seven caudal vertebrae in Andesaurus) the neural spines were slightly modified from the condition seen in Huabeisaurus.

Some interesting things to note about that anatomy of Andesaurus is that it appears to have a very long, but shallow, torso, a proportionally short tail and a relatively high humerus to femur ratio compared to other titanosaurs. Also interesting is the extremely high neural spines of the dorsal vertebrae.

Oh, and as usual, preserved material that was illustrated in the description is white, while everything else is left in gray (meaning unknown, or in some cases, non-photographed material) .

Refs--

MANNION, P. D. and CALVO, J. O. , Anatomy of the basal titanosaur (Dinosauria, Sauropoda) Andesaurus delgadoi from the mid-Cretaceous (Albian–early Cenomanian) Río Limay Formation, Neuquén Province, Argentina: implications for titanosaur systematics. Zoological Journal of the Linnean Society, no. doi: 10.1111/j.1096-3642.2011.00699.x

Calvo, J.O. & Bonaparte, J.F. 1991. [Andesaurus delgadoi n. g. n. sp. (Saurischia, Sauropoda) a titanosaurid dinosaur from the Río Limay Formation (Albian-Cenomanian), Neuquén, Argentina.] Ameghiniana. 28: 303-310. [In Spanish]

Qiqing, P. and Zhengwu, C. (2000), A New Family of Sauropod Dinosaur from the Upper Cretaceous of Tianzhen, Shanxi Province, China. Acta Geologica Sinica - English Edition, 74: 117–125. doi: 10.1111/j.1755-6724.2000.tb00438.x