定義: A habitat that is in or on a sea or ocean containing high concentrations of dissolved salts and other total dissolved solids (typically >35 grams dissolved salts per litre).
定義: a type of pectoral-fin-based swimming, also known as mobuliform locomotion. Lower frequency than fin undulation; can be described as the production of less than half a wave on the fin, similar to a bird wing flapping. Pelagic stingrays use oscillatory locomotion.
定義: length from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body