Identification of natural hybrids of gibel carp Carassius auratus gibelio (Bloch) and crucian carp Carassius carassius (L.) from lower Dyje River floodplain (Czech Republic)

Morphometric and genetic variation were examined in parental Carassius auratus gibelio and Carassius carassius individuals, and their natural hybrids. Of meristic traits, only the number of gill rakers clearly distinguished hybrids (39.4 +/- 1.4) from parental C. a. gibelio (48.3 +/- 0.7) and C. carassius (28.6 +/- 1.1). MtDNA sequences showed that the hybrids were descendants of female C. a. gibelio. Microsatellite analysis confirmed the presence in hybrids of variants typical of C. a. gibelio and C. carassius.(C) 2008 The Authors (C) 2008 The Fisheries Society of the British Isles.