X-ray Tetra

Pristella maxillaris, the only species in the genus Pristella, is commonly known as the X-ray fish or X-ray tetra because of its translucent body. It is a widely distributed and adaptable fish, found in the Amazon and Orinoco basins, as well as coastal rivers in the Guianas in both acidic and alkaline waters. Unlike most other characins, it is tolerant of (and sometimes found in) slightly brackish water. It is small (up to around 5 cm or...