Article: An oplegnathid fish from the Eocene of Antarctica

The oldest remains of the teleost family Oplegnathidae are reported from Antarctica. Fragmentary beaks with the typical coalesced teeth have been discovered. The Antarctic material presents characteristic features of members of the extant Oplegnathidae: jaws lacking lateral canines, distinctly crenulate cutting margins, teeth with narrow cutting edges that show evidence of a bipartite structure; there are also larg rounded molariform teeth on the medial face of the jaws. This record confirms that the seawater was temperate when rocks of Telms 4—5 (middle Eocene) of La Meseta Formation were deposited. Oplegnathids had at that time a wider geographical distribution than today.