#dicraeosauridae

[makairodonx]

As the breeding season arrives 145 million years ago at the beginning of the Cretaceous in what is now Argentina, a male Bajadasaurus pronuspinax flashes off his brightly-colored and high-spined neck sail to another male as a warning to stay out of his territory. If not a violent necking contest might ensue with some occasional biting at the necks.

[suryp]

Castellasaura

heavily armored, but often fairly small for their overall clade, these sauropods make up a majority of the adult herbivores on Demeter, especially within their cousins gardens.

Castellasaurus makes up a majority of the species, with Tchakaur and especially the Bauraur being the most common. other species are identified mostly with their spines, some having branching, antler-like spikes, others curling them in like an ibex, and one with almost horizontal spines that can splay out more than a meter in bulls. Bauraur, despite being the most numerous, stand out amongst these relatives, with only two species, possibly populations, which diverge in color and song, one focusing on volume and the other on dynamics.

Kla'Rabaur and Kla'aur are close relatives to Castellasaurus, but even the latter is generally recovered as outside the genus, with their macuahuitl in place of a whip. both are quite rare, and generally solitary, but their weaponry generally means they don't need numbers, and only XherSahd will hunt adults.

XherAbaur is only included here for scale. generally considered a close relative, and with adults often developing bone armor as they reach competitive size, they can closely resemble their smaller cousins. in their early years, though, all their calories are invested in size, not armor. this can make them fairly easy prey, but at nearly 2 tonnes a year, with whelps defending smaller whelps, they out-grow most carnivores by age 5, and only XherAtaur will take adults, and only when they are alone and sick.

[alphynix]

Amargasaurus cazaui was a sauropod dinosaur with a very distinctive-looking skeleton, sporting a double row of long bony spines along its neck and back. It lived in what is now Argentina during the Early Cretaceous, about 129-122 million years ago, and was fairly small compared to many other sauropods, reaching about 10m in length (~33') with a proportionally short neck compared to its body size.

And despite being known from fairly complete skeletal remains there's still a lot we don't know about this dinosaur – especially what was actually going on with those vertebral spines. While it's sometimes been depicted with skin sails over the spines, for the last couple of decades the general opinion has trended towards them being more likely to have been covered by spiky keratinous horn-like sheaths.

But recently that's been brought back into question. A detailed study of the microscopic bone structure of Amargasaurus' spines shows no evidence for keratin attachment and instead found textures associated with skin coverings, along with an extensive web of ligaments connecting the spines to each other along each row.

So maybe it had big flashy sails after all!

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[mesozoicmarket]

A dinosaur tooth of an indeterminate sauropod, possibly a diplodocoid from the Isalo III Formation in Ambondromamy, Madagascar. Although likely undiagnostic beyond Diplodocoidea at most, the morphology is similar to those seen in dicraeosaurid teeth from other deposits such as Dicraeosaurus itself. It's unknown if any of these dicraeosaurid sauropods could have been present in the Middle Jurassic deposits of Madagascar.

[justgoji]

Brachytrachelopan mesai, probably one of the most miserable sauropods in the fossil record.

With Hatsune Miku for scale:

[roygattero]

Brachytrachelopan

Commission for a line-art tattoo design.

Vector illustration.

[fundinofactoftheday]

Dinofact #113

Small in size for a sauropod, Brachytrachelopan had an exceptionally short neck - 40% shorter than any other dicraeosaurid and the shortest of any known sauropod. Brachytrachelopan measured only 10–11 metres (33–36 ft) in length and weighed only 5 metric tons (5.5 short tons).

Source: Wikipedia

[sargassos]

I am super SUPER pleased with how this turned out. I like this one. I like this one a lot.

Bajadasaurus, for day 17 of Dinovember!