Marsilius minnow
(Phoxinus marsilii)

Image source: Fero Bednar | inaturalist.org
Classification
Species:
Phoxinus marsilii
Genus:
Phoxinus - Eurasian minnows
Family: Leuciscidae - Chub family
Order: Cypriniformes - Carps
Superclass: Osteichthyes - Bony fishes