The Monotypic Sardines, Sardina and Sardinops: Their Taxonomy, Distribution, Stock Structure, and Zoogeography

Abstract

This paper reviews the taxonomy, distribution, stock structure, biochemical genetics and zoogeography of the world's two subtropical sardines, Sardina and Sardinops. We conclude that both genera are monotypic and that the differences between populations of Sardinops in different current systems are not large enough to consider them distinct subspecies. Analysis of biochemical genetics information, fossil evidence, and present and paleo-climatic conditions suggests that Sardinops did not achieve its present distribution until the Pleistocene and that westward exchange of sardines via the northern and southern west wind drift regions is possible with present climatic conditions. Transequator exchange appears to be possible only during glacial maxima and only in the eastern tropical Pacific.