AN OPLEGNATHID FISH FROM THE EOCENE OF ANTARCTICA

The oldest remains of the teleost family Oplegnathidae are reported fr om Antarctica. Fragmentary beaks with the typical coalesced teeth have been discovered. The Antarctic material presents characteristic featu res of members of the extant Oplegnathidae: jaws lacking lateral canin es, distinctly crenulate cutting margins, teeth with narrow cutting ed ges that show evidence of a bipartite structure; there are also large rounded molariform teeth on the medial face of the jaws. This record c onfirms that the seawater was temperate when rocks of Telms 4-5 (middl e Eocene) of La Meseta Formation were deposited. Oplegnathids had at t hat time a wider geographical distribution than today.