Abstract

Paleobiogeographic distribution within the larger, trematophore miliolids was evaluated using presence/absence (Parsimony Analysis) patterns and distributional extension of 7 genera and 47 species from the Coniacian to the Oligocene. The oldest group of larger miliolids (from late Cretaceous), represented by four parallel genera (Periloculina, Lacazina, Pseudolacazina, Idalina) from the southern Pyrenean province exhibits an endemic character. Later periods of the Senonian with uniform distribution of miliolids over the shallow-marine carbonate environments in the western and central Neotethys are characterized by reduction in generic diversity and in abundance of individuals. The morphological analysis indicated four major biogeographic regions for the Eocene larger Miliolids: 1) the Caribbean, 2) the “European” Neotethys (western, central and eastern), 3) the North African Neotethys (southern) and 4) the Indo-Pacific. The morphological biogeographic pattern corresponds to the circum-global Eocene current ocean system and the prevailing temperature sea surface gradient along tropical-subtropical paleolatitudes. A tendency to endemism can be observed for Fabulariids in the Caribbean during the Middle and Upper Eocene, and for Lacazinella during the Middle and late Eocene to Oligocene in the New Guinea and Molucca regions.

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