Misgurnus fossilis (Linnaeus, 1758)

Iftime, Alexandru & Oţel, Vasile, 2025, An annotated systematical checklist of the Romanian ichthyofauna, Zootaxa 5654 (1), pp. 1-64 : 10

Misgurnus fossilis (Linnaeus, 1758)

A native, widespread freshwater species, living in slow-flowing or stagnant water (including the Razim lagoon), in both intra- and extra-Carpathian drainages ( Bănărescu 1964; Wilhelm et al. 2002; Oțel 2007; Imecs et al. 2011; Imecs & Nagy 2016; Cocan & MireȘan 2018; Năstase et al. 2022; Togor et al. 2022; Nagy et al. 2023). Has undergone severe decline/range reduction ( Wilhelm et al. 2002; Imecs et al. 2011; Imecs & Nagy 2016; Togor et al. 2022).

Fam. Nemacheilidae

Barbatula barbatula (Linnaeus, 1758)

A native, widespread freshwater species, found in rivers in the montane and hill areas, in both intra- and extra-Carpathian drainages ( Bănărescu 1964; Cocan & MireȘan 2018; Nagy et al. 2023); isolated populations in the Romanian Plain ( Nalbant 1976; Bănărescu & Nalbant 1980).

Fam. Cyprinidae

Carassius auratus (Linnaeus, 1758)

A widespread species, found in Romania under two forms, often described as (putative) species: Carassius gibelio (Bloch, 1783) , a native (at least for the Danube and its large tributaries; see discussion by Oțel 2019; Iftime & Iftime 2021, and literature quoted therein), partly gynogenetic, fresh- and brackish-water form, living in slow-flowing or stagnant waters, now widespread in lowland and hill areas, partly as a result of stocking ( Bănărescu 1964; Manea 1985; Oțel 2007; Cocan & MireȘan 2018; Oțe, 2019; Iftime & Iftime 2021; Nagy et al. 2023; Drăgan et al. 2024), and the Asian Carassius auratus , which is non-native, found in ornamental and other fishponds, and occasionally as an escape (Oțel 2019; Iftime & Iftime 2021).

The two putative Carassius species above might be regarded as forms of the same species: C. auratus , as they overlap morphologically (Oțel 2019; Comia & Morris 2024), they are not distinct in some phyletic analyses, and C. gibelio is not exclusively gynogenetic, but alternatively, reversibly gynogenetic and sexual, with evidence of gene flow between it (as the sexual form) and C. auratus ( Gu et al. 2022; Jacques et al. 2024, and literature quoted therein) in a context of recurrently variable intraspecific ploidy (Qin et al. 2013; Luo et al. 2014; Liu et al. 2017; Li et al. 2018).