 The winter flounder is one of five species in the genus Pseudopleuronectes along with the Yellow-striped flounder, Cresthead flounder, Marbled flounder, and Dark flounder.It is the only congener to inhabit the Atlantic Ocean.Winter flounder can be differentiated from the commonly co-occurring Summer flounder (Paralichthys dentatus) by their small teeth and eyes nearly always positioned on the right side of their bodies.