Here's "Chapi". That is the nickname of an armoured titanosaur found at Lo Hueco (Cuenca Spain) with remains of its dermal armor associated.
Me and my supervisors (Francisco Ortega and José Luis Sanz) have studied the osteoderms from the Upper Cretaceous of Europe. The study has concluded that the most primitive lithostrotians, as those would only have osteoderms of the bulb and root morphotype. This morphotype is highly variable, with rounded flat osteoderms and elongated, spiny osteoderms.
In order to draw it, as we do not have enough data on this sauropod, except for its osteoderms we have drawn a quite robust sauropod (armoured animals appear to be more robust) with an elongated manus (recently presented at the EAVP) and the skull of Tapuisaurus (a beautiful titanosaur).
I would like to thank for letting me use his skeletal drawing of Malawisaurus as a guide for positioning the dermal armor.
Vidal D, Ortega F, Sanz JL (2014) Titanosaur Osteoderms from the Upper Cretaceous of Lo Hueco (Spain) and Their Implications on the Armor of Laurasian Titanosaurs. PLoS ONE 9(8): e102488. doi:10.1371/journal.pone.0102488
Congratulations for both Carlosdinos and Danny Vidal
But please I need some explanations.
I don’t understand the long spines on the tail. According to your paper, the size of the longest osteoderm is caused by the very elongate "root". The "bulbous" part of this osteoderm being of normal size and concave. So in this illustration, the longest spines on the tail are osteoderms upside down, the root forming the spine ? Or the concave bulb (without bony spine) like HUE-01330, support a fully keratinized spine longer than the one of the osteoderms with convex bulb (with a bony spine) such HUE-02000 or MDE-C3-192 ? In both cases, it's rather strange. Anyway, it seems that the appearance of these animals were even more extraordinary than previously thought.
By the way, maybe one of the two titanosaur from Lo Hueco is the same genera with the new titanosaur from Cruzy.
The roots do not form the spike, but rather the bulb would support a fully keratinous spike. Like Rhinoceros. Here's why we think it could be:
The longer osteoderms indeed do not have a bony spine, but rather are concave. Nevertheless, their cingulum is the thickest of all osteoderms (in relation to the diameter of the bulb). The surface texture of the bulb, pitted and radiated, is very similar to that of a Rhinoceros horn insertion area.
We thought that while it seemed reasonable that titanosaurs had flat, not very separated keratinous scutes (the rounded osteoderms, with bulbs sub equal in length to the roots), it would be weird if they had small, concave scutes separated forty five centimetres from each other. We thought a keratinous spine would work better, as it would be anchor to that well developed cingulum. Large keratinous spines would have the long, bony root as a counterbalance as well (so they could project caudo laterally) and would be separated by forty or more centimetres, which would allow them to be that long at the very least, so they could be a passive defence covering the 45 cm of root that separated each spine.
Those osteoderms with larger bony spine (convex bulbs) like HUE-02326 or MDE-C3-192 present very different ornamentation: radiating fibers, like those of cattle bony horns. Their cingulums are as well not as developed as in very elongated osteoderms. Cattle horns have just thin keratin sheaths that cover the bony core, so we thought those osteoderms with radial fibbers would work the same way.
This is just pure speculation without any hard evidence, but IMHO what you could say would be the "most likely way". Indeed, the appearance of these sauropods would have been spectacular.
About that last question, we know both morphotypes found at Lo Hueco have autapomorphies not present in French titanosaurs (even the remains at Cruzy). More on that will (soon) be published, so please be patient
Thank you very much for the comments.
That's what I thought but I was not sure of the coexistence of bony spines with fully keratinous spines. Titanosaurs having plates, spines with a bony core, and long spines fully keratinized. This seems plausible indeed, what a remarquable variety of armors. I love even more these sauropods, that were probably more dangerous preys for the predators.
Well, the two titanosaurs from Lo Hueco, the one from Cruzy, and maybe the titanosaurs skeletons from the Arcovenator quarry, if all are news for the science, the titanosaur diversity of the Ibero-Armorican Island will more than double. Beside the differences in the body proportions and the shape of their teeth, suggesting differents ecological adaptations, may explain the coexistence of some species, it is probable that all these titanosaurs don’t lived at the same time. In southern France, the titanosaurs genera have been found in differents regions without stratigraphic correlations. It not sure if Ampelosaurus, Atsinganosaurus and the Cruzy titanosaur were contemporary, or if they lived at different times inside the middle to late Campanian interval. I think the sole exception is in Provence where titanosaurs skeletons are known in two successive formations of the same area : the Atsinganosaurus quarry is much older (maybe middle Campanian or early-late Campanian) than the one where found the yet undescribed titanosaurs skeletons of the Arcovenator site (probably younger level of the late Campanian).
The knowledge of the succesive fauna of this island is still incomplete but new discoveries are ongoing and are really exciting.
Oh, I love you too! XD