Tetra Head & Tail Light (Hemigrammus ocellifer)

Hemigrammus ocellifer is a South American freshwater fish, also described by the synonyms Hemibrycon ocellifer and Tetragonopterus ocellifer. Common names include beacon fish, beacon tetra, head-and-tail light tetra and head-and-taillight tetra. It is found in the rivers of Guyana, Suriname, French Guiana, and the Amazon Basin of Brazil and Peru.

Most specimens offered for sale in the aquatics trade are tank-raised.

It has a maximum size of 5 centimetres (2.0 in); the sexes are distinguished by mature females being fuller-bodied.