Sunday, June 14, 2015

The forgotten Xinghesaurus

Some dinosaurs, like Tyrannosaurus, get far too much attention. Many others get much less, but still get attention. And there's the obscure.

Xinghesaurus is one of the most obscure dinosaurs ever named. It's not even formally described! So far, the palaeocommunity has ignored the very existence of this mysterious sauropod. There is no single raw measurement or even a single mention in a survey.

A Xinghesaurus mount was displayed in a Tokyo museum exhibit, one which also contains a mounted skeleton of the enormous Mamenchisaurus sinocanadorum(supposedly claimed to have a mass upwards of 70 tonnes, but is likely closer to 50 tonnes).


A closer look, perhaps?



Much better. Seems to be a nemegtosaurid with similarities to Huabeisaurus.

Here's one from the rear:


This is what we have of it so far. A mounted skeleton without a description paper or a single bone measurement. We don't even know how much of it is reconstructed.

But maybe we can estimate it's size based on these pictures?

Well, we can, but we have to take the results with a grain of salt. For starters, the bones can be compared with something close in proximity to it as to minimize the impact of perspective, such as the people surrounding the mounted skeleton.


Using that man bending down just beside the Xinghesaurus' hindlimb as a guide, the femur is around 2/3 of the man's height. Assuming that the man is at the average human height of ~165 centimeters, the Xinghesaurus femur would be about ~110 centimeters long. If we use the average height for Japanese males instead, which is about ~170.7 centimeters, the Xinghesaurus femur ends up at ~113.8 centimeters long.

Using the picture of the Xinghesaurus' rear, the resulting femur length could be used to estimate the hip height and possibly body width.

 
The hip height, which is approximately ~2.379 times the femur length, would be about ~2.617 meters based on the ~110-centimeter femur, or ~2.708 meters based on the ~113.8-centimeter femur.

The width at the hips(~75% of femur length) would be about ~82.5 centimeters based on the ~110-centimeter femur and ~85.35 centimeters based on the ~113.8 centimeter femur.

Based on the very limited information we have to date, Xinghesaurus seems to be a small sauropod, although you still don't want it to step on your toes.

But how large is it overall, at least based on the mount? We'll see in the next post.