Pristella maxillaris, commonly known as the X-ray tetra, is renowned for its translucent body, allowing a view of its internal structure. This small freshwater fish is native to South America's Amazon basin. It thrives in schools, exhibiting peaceful behavior, and plays a crucial role in aquatic ecosystems by controlling insect populations.

Pristella maxillaris, commonly known as the X-ray tetra, is native to the coastal rivers of South America. Its natural distribution includes parts of the Amazon and Orinoco River basins, primarily found in Brazil, Guyana, and Venezuela.

The X-ray tetra inhabits clear rivers and streams with a moderate to slow current. These waters are typically warm, with temperatures ranging from 22 to 28 degrees Celsius (72 to 82 degrees Fahrenheit), and slightly acidic to neutral pH levels, around 6.0 to 7.5. The environment is often well-oxygenated, with abundant aquatic vegetation.

Pristella maxillaris is a small schooling fish that thrives in freshwater environments with dense plant life. It plays a role in the ecosystem as both a prey species for larger piscivores and a consumer of small invertebrates and plant matter. The presence of aquatic vegetation provides shelter and breeding grounds, making it an important component of its ecological niche.