Squamation of the thelodont agnathan Phlebolepis

The study of more than 250 articulated specimens of the thelodont Phlebolepis elegans (Upper Silurian, Estonia) has shown how the morphology and sculpture pattern of scales depend upon their position on the body. Five morphological scale varieties are distinguished for several Silurian thelodonts. Phlebolepis ornata n.sp. from the Estonian Upper Silurian (lower Ludlow) is described.