Micropaleontological study of the Moroccan Mediterranean western coastline foraminifera and their morphological abnormalities

摘要

In order to contribute to the identification of the current faunistic composition of the Moroccan Mediterranean western coastline foraminifera, sediment from 4 stations have been analyzed, along with some abiotic parameters (pH, dissolved oxygen, temperature, and salinity), In order to characterize their populations, different Ecological indices were calculated and compared in the various samples. A total of 3451 individuals belonging to 14 species were recognized (90,26% hyaline, 9,74% porcelaneous, and none agglutinated test was found), all assemblages were dominated mainly by Elphidium crispum, Ammonia beccarii , and subordinately by Quinqueloculina sp1 and Heterolepa dutemplei . All sampling sites showed remarkable similarity in the Foraminiferal assemblages, and the Oued Nigro station is considered the wealthiest and densest site, whereas Oued Martil records the lowest values of those parameters. On the other hand, the Sample from M'diq presents the lowest diversity index even if it is the second in terms of density. The faunistic analysis had also allowed the observation of some morphological abnormalities only found in the Oued Nigro station, affecting some individuals' tests. A small-sized chamber mainly manifests the abnormal appearances in the spiral whorls and calcification defects in the calcareous wall.