Chrysophyte algae live predominantly in freshwater habitats, therefore marine chrysophyte stomatocysts are less common and poorly documented. Here we report on the occurrence of two unknown chrysophycean stomatocysts in a complex epizoic biofilm formed on a carapace of a loggerhead sea turtle (Caretta caretta) found injured on the southeastern coast of the Adriatic Sea and admitted to the Sea Turtle Rescue Centre in Aquarium Pula, Croatia. Stomatocyst #1 is characterized by a thickened circulus giving the cyst an asymmetrical outlook whereas stomatocyst #2 has a thick, wide, irregularly shaped collar. Detailed morphological investigations based on scanning electron microscopy observations and comparison with known chrysophyte stomatocysts worldwide, showed that both should be described as new to science following the guidelines of the International Statospore Working Group (ISWG).