Features of Inner Ear Morphology of Gibel Carp Carassius gibelio (Cyprinidae)

— The mutual arrangement of the inner ear structures (membranous labyrinth) and their localization in the neurocranium are studied in gibel carp Carassius gibelio . The upper anterior part of the labyrinth (pars superior) is located at a substantial distance from its lower posterior part (pars inferior). The ventral region of the pars superior is freely located in the depression of the upper part of the prootic. The pars inferior including the sacculus and lagena is enclosed in a bone capsule of the basioccipital and bounded from above by a thin bony membrane (tectum basioccipital). The pars inferior structures that participated into the reception of vibrations of the swim bladder wall are located at the same level as the elements of the Weberian apparatus. The crus communis of the pars superior transits into the elongated ductus utriculus-sacculus, which enters the bony capsule through the medial opening in the tectum basioccipital. An updated scheme of the gibel carp inner ear is illustrated. The morphological and functional properties of the membranous labyrinth of the representatives of the group Otophysi are discussed.