Zlatni vijun (Sabanejewia balcanica)
Ovo je autohtona vrlo rijetka vrsta koja nastanjuje Kupu, srednji tok Save, Unu i donji tok Drave. Ova ribica naraste do 12 cm. Tijelo mu je zmijoliko, izduženo i bočno spljošteno. Na relativno maloj glavi su mala usta, koja okružuju tri para dugih brčića. Hrani se algama, sitnim beskralježnjacima i organskim ostacima sa dna.
Uzrok ugroženosti su onečišćenje gornjih tokova rijeka, pregrađivanje i regulacije vodotoka.
Golden loach (Sabanejewia balcanica)
This is an autochthonous, very rare species that inhabits the Kupa, the middle reaches of the Sava, the Una and the lower reaches of the Drava. This fish grows up to 12 cm. Its body is snake-like, elongated and flattened laterally. The back is brownish-green marbled, with 10–16 reddish spots, between which are light yellow spots. The sides are golden brown, with 12 to 16 dark brown spots. The dorsal and tail fins are spotted. On the relatively small head there is a small mouth, with three pairs of long barbels around it. It feeds on algae, small invertebrates and organic remains from the bottom.
The cause of endangerment is the pollution of the upper reaches of rivers, water barriers, and regulation of watercourses.