Ossa Aliena

Okay, so as kindly pointed out, my previous manifestation of the Vectilian skeleton was not quite biomechanically correct. If such an articulated animal existed and jumping was a mode of locomotion, then the forces acting on the body would not allow for forward and upward motion. The center of mass is too far forward, and the animal would tumble onto its face. In jumping animals on earth, such as frogs, fleas, and grasshoppers, the center of mass is almost directly in the middle of the long axis.

So to counter this I have made a few changes, as well as added a few other bones, such as the Uncus, which is involved in moving the Costal PLate backward to pump air through the respiratory system. As well, the Sagittal Plate is now divided into two, with the Abdominal Axis added to give the animal a little more flexibility (though loricates are by design not the most flexible animals, and their lack of axial flexion is the main reason why loricates have lost out to chiridopods as the dominant terrestrial megafaunal phylum). Most important are the virgae, two partially ossified rods that stretch posteriorly and have varying functions in different species, but their primary function is as a counterweight when jumping. In the air they are also used to adjust the yaw and pitch of the body for greater accuracy when landing.

I have included a silhouette of the fleshed out animal (not necessarily the same species as represented by the skeleton), showing the typical splayed out stance, misrepresented as upright in the skeleton. When jumping, the fulcimentum is a major component, lifting the body at an angle while the bracchia position themselves off the ground, much like a jumping spider, giving the first push into the air to make the angle, whereupon the vectis and the jumping legs take over.