First report of the Chinese sleeper Perccottus glenii Dybowski, 1877 in the Drava River, Croatia

First record of highly invasive Chinese sleeperPerccottus gleniiDybowski, 1877 (Perciformes: Odontobutidae) in the Elbe River Basin, Czechia

“…The fish was collected on January 8, 2023, during fish harvest in the stream below the dam. The morphometric and meristic characteristics were consistent with the species delimitation according to Horvatić et al . (2022).…”

“…The fish was collected on January 8, 2023, during fish harvest in the stream below the dam. The morphometric and meristic characteristics were consistent with the species delimitation according to Horvatić et al (2022). The specimen had a standard length of 67 mm, a total length of 79 mm, and a weight of 8.1 g. Eight meristic features on the left side of the body matched the species description: six rays in the first dorsal fin, 13 rays in the second dorsal fin, 13 rays in the pectoral fin, 4 rays in the ventral fin, 9 rays in the anal fin, 38 scales in the lateral line, 14 scales in the transverse row, 9 scales in the circumpenducular row (Horvatić et al, 2022;Nikolić et al, 2021).…”

“…The person kept the fish alive until it was picked up by authors on January 13, 2023, and brought to the laboratory of the Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences in České Budějovice. There, the life of the specimen was sacrificed by an overdose of anaesthetics (MS −222) and morphometry (standard length, total length in mm, weight in g) and meristic counts were performed according to Horvatić et al (2022) following the guide for first records (Bello et al ., 2014). A picture was taken (Figure 1b) and the specimen was fixed in 40% formaldehyde solution and stored in the depository of the Institute of Hydrobiology.…”

“…(2022). The specimen had a standard length of 67 mm, a total length of 79 mm, and a weight of 8.1 g. Eight meristic features on the left side of the body matched the species description: six rays in the first dorsal fin, 13 rays in the second dorsal fin, 13 rays in the pectoral fin, 4 rays in the ventral fin, 9 rays in the anal fin, 38 scales in the lateral line, 14 scales in the transverse row, 9 scales in the circumpenducular row (Horvatić et al ., 2022; Nikolić et al ., 2021). To our knowledge, the Chinese sleeper has not yet been detected in the Czech Republic (Chobot & Němec, 2017; Froese & Pauly, 2000); however, its range includes almost all neighbouring countries, Germany, Poland, and Slovakia, except for Austria (Grabowska et al ., 2009; Koščo et al ., 2003; Reshetnikov & Schliewen, 2013) and thus its invasion was expected.…”

“…As for the situation in the identified occurrence area, three kilometres in the southwestern direction downstream is the Klabava Reservoir with an area of 39.2 ha and rich riparian vegetation. The Chinese sleeper prefers waters that either have weak flow or are stagnant, with well-developed aquatic vegetation, floodplains with well-developed vegetation, riparian zones of lakes, marshy waters, and even swamps (Horvatić et al ., 2022; Reshetnikov, 2004). Reaching this reservoir can support them with a suitable habitat for their establishment, where measures will be very difficult to implement.…”