Weberian Apparatus

Also found in: Wikipedia.

Weberian apparatus

[vā′bir·ē·ən ‚ap·ə‚rad·əs]
(vertebrate zoology)
A series of bony ossicles which form a chain connecting the swim bladder with the inner ear in fishes of the superorder Ostariophysi.

Weberian Apparatus


in fishes, an apparatus that senses, transforms into mechanical displacement, and transmits (by means of the movable element of the first vertebra and the cerebrospinal fluid) to the inner ear vibrations of the walls of the air bladder (sound resonator). It consists of four pairs of bones, movably articulated to one another, that connect the air bladder with the inner ear. The bones of the Weberian apparatus are modified parts of the first vertebrae and the third rib. The Weberian apparatus is named for the German anatomist E. Weber, who first described it in 1820. The degree of development of hearing in fishes is associated with the presence or absence of the Weberian apparatus. Fishes that have the Weberian apparatus (Cyprinidae, Siluridae, Characinidae, Gymnotidae) are capable of perceiving sounds with a frequency up to 13 kilohertz; fishes without the Weberian apparatus perceive sounds with a frequency up to 2.5 kilohertz.


Protasov, V. R. Bioakustika ryb. Moscow, 1965.


References in periodicals archive ?
This feature, termed the Weberian apparatus (WA), is an accessory hearing organ that transduces sound from the swim bladder to the inner ear.
vertebral counts included the four vertebrae of the Weberian apparatus and the terminal vertebral centrum was counted as a single element.
In the Catfish species the number of vertebrae fused to conform the Weberian apparatus is about five or six (BUITRAGO, 2006) so this skeleton character may be confuse when used to define their numeric relation with myomeres number.
A separate chapter traces the origin and evolution of the Weberian apparatus, and compares the use of mycological versus osteological structures in phylogenetic reconstructions.