The Young Argentine Sea, Its Ichthyofaunistic Colonization and Its Traumatic Evolution

ROMAN, JORGE MARTIN; SABADIN, DAVID E.; FIGUEROA, DANIEL E.; CHIERICHETTI, MELISA; BARBINI, SANTIAGO A.; SCENNA, LORENA; BELLEGGIA, MAURO

Austin

Encuentro; Joint Meeting of Icthyologists and Herpetologists; 2017

Kansas State University

Atthe beginning of the Mesozoic Era (140mA), the Argentine Sea did notexist, the Gondwana was probably a set of united plates with shallowwater. In the middle of that Era (112Ma) the plates separate witheach other allowing shallow marine intrusions, where an endemic fishfauna develops, as some coelacanths. At the end of the Mesozoic Era,in the Cretaceous period (66 Ma), the south Protoatlantic joins withthe North Atlantic (Tethys Sea in part), and allows the fish fauna ofTethyan origin colonize the south, reaching Antarctica. The openingof the Drake Passage in the Oligocene period (33 Ma), in the CenozoicEra, enables the cold waters of the Pacific Ocean to penetrate in thesouth Atlantic, causing drastic effects on the thermophilic fauna.Successive glaciations in the Quaternary Period (2 Ma-10,000A),allowed the polar front to advance several times to lower latitudes,leaving the Argentine Sea within it. This traumatic development inthe constitution of the southwest Atlantic, is reflected in theheterogeneous composition of the Argentine marine ichthyofauna, withcosmopolitan, Tethyan, Pacific, Antarctic, Gondwanic and ownlineages.p { margin-bottom: 0.25cm; direction: ltr; color: rgb(0, 0, 0); line-height: 120%; }p.western { font-family: "Times New Roman", serif; font-size: 12pt; }p.cjk { font-family: "Times New Roman", serif; font-size: 12pt; }p.ctl { font-family: "Times New Roman", serif; font-size: 12pt; }a:link { color: rgb(0, 0, 255); }