New discoveries of Devonian Vertebrates from South America, and implications for Gondwana-Euramerica contact

A new fossil fish fauna from western Venezuela provides the first South Ame rican Devonian record of antiarch and phyllolepid placoderms, and sarcopter ygians including lungfishes, groups widely distributed on other continents. Endemic elements in the fish fauna indicate Gondwana affinities, and the a ge of the phyllolepid placoderm occurrence is consistent with a model of bi otic dispersal between Gondwana and Euramerica near the Frasnian-Famennian boundary. A narrow marine barrier separating northern and southern landmass es is indicated, in contrast to the wide equatorial ocean for the Late Devo nian postulated from palaeomagnetic data. (C) 2000 Academie des sciences / Editions scientifiques et medicales Elsevier SAS.