Loganellia (Thelodonti, Agnatha) from the Lower Silurian of North Greenland

Abstract

Isolated thelodont scales from several Lower Silurian samples from North Greenland are re-described and compared with European forms, to assess their taxonomical, stratigraphical and palaeogeographical significance. Loganellia scotica s. s. (TRAQUAIR, 1898) scales, described from the Lafayette Bugt Formation, are more restricted than commonly supposed, being found only in Scotland and North Greenland. Reassignment of some thelodont scales from L. scotia to L. grossi (FREDHOLM, 1990) suggest a middle Wenlock age for the Kap Morton Formation.