Grajau Darter
Characidium grajahuense
- Critically endangered
- Card rarity: Legendary
- Fish

Characidium grajahuense is a fish in the family Crenuchidae. It is native to South America and is found in the coastal streams between Guanabara Bay and the Mangaratiba, in Rio de Janeiro, Brazil.
Classification
- Class
- Actinopterygii
- Order
- Characiformes
- Family
- Crenuchidae
- Genus
- Characidium