Clarias gariepinus (Burchell, 1822)

Clarias gariepinus View in CoL X Heterobranchus longifilis Valenciennes, 1840

A non-native freshwater hybrid, introduced deliberately in aquaculture ( Iftime & Iftime 2021; Năstase & Năvodaru 2023).

Fam. Ictaluridae

Ictalurus punctatus (Rafinesque, 1814)

A non-native freshwater species, introduced deliberately in aquaculture and spreading from introductions beyond the country, found in some fishponds and in the Prut river ( Iftime & Iftime 2021). Also recorded in recent years in the Danube arms in the Delta (Bălan, M., Sevastian, A., Togor, A., unpublished records via Ichthyology of Romania Facebook group, with our [V. Oțel] contribution to identification).

ORD. SALMONIFORMES

Fam. Coregonidae

Coregonus peled (Gmelin, 1789)

A non-native freshwater species, deliberately introduced and grown in aquaculture, also introduced in a few alpine lakes (Retezat) and reservoirs; its present-day survival is unclear, but highly unlikely ( Iftime & Iftime 2021).

Fam. Salmonidae

Salvelinus umbla (Linnaeus, 1758)

A non-native freshwater species, deliberately introduced (from Austria —Togor, A. pers. comm.) and grown in aquaculture ( Iftime & Iftime 2021 [as S. alpinus (Linnaeus, 1758—but see discussion in Kottelat 1997; Kottelat & Freyhof 2007]); also found in free waters, namely in the BeliȘ-Fântânele reservoir on the SomeȘul Cald river, where it was, presumably, illegally introduced ( Nagy et al. 2023 [as S. alpinus (Linnaeus, 1758]); there are more undocumented introductions—Togor, A. pers. comm.

ORD. CYPRINODONTIFORMES

Fam. Poecilidae

Subfam. Poeciliinae

Poecilia reticulata Peters, 1860

A non-native species, transiently found in thermal water (Băile Felix, 1 Mai), event reproducing for some time, e.g. in 1991 (Freyhof, J., pers. comm.) and other urban ponds (Bucharest) as an aquarium release, but not established ( Iftime & Iftime 2021) .