Gemuendina stuertzi, ray-like Placoderm Stegosaurus and few museum replicas are

and few museum replicas are more beautiful or intriguing than the Berlin specimen of Archaeopteryx

All Arthropods have a chitinous exoskeleton and jointed limbs

About 125 million years ago

9---Mixopterus

Gemuendina stuertzi, ray-like Placoderm Stegosaurus and few museum replicas areGemuendina stuertzi is a placoderm of the order Rhenanida, of the seas of Early Devonian Germany. In life, Gemuendina resembled a scaly ray with an upturned head, or a large finned stargazer. G. stuertzi is often invoked as an example of convergent evolution with its flat body and huge, wing like pectoral fins it has a strong, albeit superficial similarity to rays. Unlike rays, however, both Gemuendina`s eyes and nostrils were placed atop the head,