Sunday, the ROV spied this awesome beast, a weird sea urchin in the genus Aspidodiadema. Although there's at least one species known in this area, A. hawaiiensis, I'm not sure that this is the same thing.
I've talked about this urchin before. The spines bow out from the central body and touch the bottom rather than simply projecting outward as they do in other species. They are unusual in that they use their spines to "walk" along the sea bottom.
Here's a diagram of another species but with the "walking tips" clearly deployed on the bottom
On Sunday, they spied ANOTHER Aspidodiadema sp. But the video actually captured the unusual TIPS of the walking spines!!!
Look at the red arrows below pointing to the "walking cups" on the spines that the urchin uses to move!
Think of the spines like the long legs on the spider robot from Johnny Quest!
This all makes sense though. Spines are how these animals interact with their environment. In these deep-sea habitats where you have a lot of water currents and unstable bottoms, these spines help them. Either as support or to help move efficiently where a soft tube foot might not.
Weird. But I love figuring out strange sh*t like this!!