Longfinned Triplefin
Ruanoho decemdigitatus
- Least concern
- Card rarity: Common
- Fish

Ruanoho decemgitatus, the longfinned triplefin, is a species of fish in the family Tripterygiidae. It is endemic to New Zealand. It is marine fish that occurs in shallow water on rocks and cobbles on silty reefs in semi-sheltered areas. It can grow to 12 cm (4.7 in) total length.
Classification
- Class
- Actinopterygii
- Order
- Blenniiformes
- Family
- Tripterygiidae
- Genus
- Ruanoho