Potamotrygonidae, which I'm sure most of you are familiar with, is the only family of freshwater stingrays, other than certain Dasyatidae species. Well, what some of you might know is that it contains but one marine genus - Styracura.
![1637419795614.png 1637419795614.png](https://www.monsterfishkeepers.com/forums/data/attachments/1234/1234734-e6d0c3e33fa9bc5b89348b7fbca0ceba.jpg)
![1637419687646.png 1637419687646.png](https://www.monsterfishkeepers.com/forums/data/attachments/1234/1234733-35c4dc5dbe9370513c60495f4fbe4085.jpg)
Pictured above are the Pacific whiptail stingray, Styracura pacifica, (left) and the Caribbean whiptail stingray, Styracura schmardae. (Right)
These are essentially marine motoro rays, only much larger. You can see the family resemblance. Schmardae is capable of tolerating low salinities, and even enter the Amazon's estuary from time to time.
![1637419795614.png 1637419795614.png](https://www.monsterfishkeepers.com/forums/data/attachments/1234/1234734-e6d0c3e33fa9bc5b89348b7fbca0ceba.jpg)
![1637419687646.png 1637419687646.png](https://www.monsterfishkeepers.com/forums/data/attachments/1234/1234733-35c4dc5dbe9370513c60495f4fbe4085.jpg)
Pictured above are the Pacific whiptail stingray, Styracura pacifica, (left) and the Caribbean whiptail stingray, Styracura schmardae. (Right)
These are essentially marine motoro rays, only much larger. You can see the family resemblance. Schmardae is capable of tolerating low salinities, and even enter the Amazon's estuary from time to time.