Abstract
Artemia franciscana is a native species to the New World, and became an exotic species to most parts of the world. The Egyptian hypersaline, continental Qaroun Lake (Fayoum Governorate, Middle of Egypt) is subjected to a gradually increasing salinity rates that approximate or exceed these of seawater. Artemia populations there are known to be parthenogenetic. Yet, these populations started to exhibit abnormal morphologies. Therefore, Qaroun Lake samples of Artemia were subjected to several morphological, biometric, and molecular phylogenetic analyses for accurate species identification and phylogeographic origin approximation. These analyses revealed the existence of the alien sexual species of brine shrimp A. franciscana in Qaroun Lake. The characteristics of the subspherical frontal knob with several spines on the top, ovisac lateral triangular lobe on both sides and its projection together with the biometrics confirmed this species morphotype. DNA barcoding and other molecular analyses based on PCR-based amplification and sequencing of the barcode region of the cytochrome oxidase subunit I gene (COI) exhibited that all the collected samples belong to five haplotypes. Egyptian A. franciscana COI sequences phylogeny and pairwise distances analysis exhibited closer proximity to Latin American strains than to the Northern American ones. A. franciscana presence may be ascribed to the migratory birds present in Qaroun Lake protectorate, since no marine aquaculture activity in Qaroun Lake is known. Therefore, and for the best of our knowledge, this is the first record of the invasive A. franciscana in Egypt.