Neogene ostracods from the Solimões Formation (Atalaia do Norte, Amazonas State, Brazil), with the description of two new species

Abstract

The analysis of the ostracods from three boreholes (1AS-7D-AM, 1AS-8-AM, and 1AS-31-AM) drilled in Atalaia do Norte town, Amazonas State, Brazil, allowed to recognize 30 species and nine genera. Cyprideis is the most abundant and diverse genus and is represented by 19 species already identified for the Solimões Formation, besides two new species described herein: Cyprideis atalaiensis sp. nov. and Cyprideis dictyon sp. nov. Intraspecific morphological variability, as well as the presence of nodes and tubercles, are observed in some species of Cyprideis and interpreted as a response to the paleoenvironmental changes during the Neogene in western Amazon region. Keywords: Cyprideis, morphological variability, paleoenvironmental changes, western Amazonia.