Description: The Heterostracans were a marvelously diverse group of agnathan fish. Typically there are two large bony plates protecting the body, one on the dorsal and one on the ventral side. They arose during the Silurian and achieved their greatest diversity during the Devonian. One of the most successful groups were the pteraspids, meaning wing shield, a term that refers to the spines that projected from the sides of the body of many of them. One feature that stands out (literally) is the rostrum. While early members had relatively short rostra, later ones developed exceptionally long ones for an as yet unknown purpose. This one is known as Rhinopteraspis, and has an exceptionally long rostrum. Seen here is the body shield, most of the rostrum, and a number of disarticulated scales forming a “rubble pile” to the rear. Note the growth rings evident in the armor plates. The matrix in which these are found is quite difficult to prepare, but most of the rostrum and head shield have been prepared substantially free of the entombing rock. The difficult in preparation and rarity commands a commensurate price, here less than the four figure values usually seen. I have included an artist’s rendition of the complete animal.