"X" is for X-Ray Tetra
The X-Ray Tetra sounds like a science fiction character in a Japanese anime film. Actually, they are a small species of schooling fish mostly found in the Amazon River's coastal waters in South America and Africa.
This fish has a faint (slight , a little) golden color of its tanslucent (see through) skin, so because of this, they are also known as the "Water Goldfinch".
Because of their electric-like flashy color, almost like a neon light, they have become the most commonly kept freshwater fish in aquariums around the world. They have hard bodies and are easy to care for.
In the wild, they travel in schools, hundreds of them swimming together in a group. They do this for protection and to find food. There are more than 150 kinds of tetra, of various neon-like colors, reds, blues, green and yellows.
Due to their small size, they fall prey (become eaten by other animals) to larger fish, eels, and other sea life. Of course, their bright colors make them easy to spot in the clean freshwater of rivers and streams.
They do, however, make beautiful fish pets. ! (V.C)
X-ray tetra プリステラ（淡水熱帯魚）
schooling fish 群れを成して泳ぐ魚
flashy color けばけばしい色合い
travel in schools 群れをないして移動する
fall prey 餌になる