First recording of molluscs larvae from Southern Iraq

The study focused on the diagnosis of gastropods and pelecypods classes species, mostly in the planktonic larvae stage, to be used as evidence of marine transgression of mid-Holocene in Southern Iraq. Three biofacies were identified depending on microfossils (planktonic larvae) primarily as well as the nature of sediments. They were defined as Biofacies1 (B1), Biofacies2 (B2) and Biofacies3 (B3). Three biofacies were identified depending on microfossils (planktonic larvae) primarily as well as the nature of sediments. They were defined as Biofacies1 (B1), Biofacies2 (B2) and Biofacies3 (B3). where Biofacies1 (B1) can be placed within the marine transgression unit that occurred in middle of the Holocene, While Biofacis2 (B2) can be considered within the marine regression unit, which is approximately 4000 Yr BP, and the Biofacies3 (B3) may indicate that the occurrence of fluctuation in the sea level at the end of Holocene.