Kype

A kype is a hook-like secondary sex characteristic which develops at the distal tip of the lower jaw in some male salmonids prior to the spawning season.^[1]^[2] The structure usually develops in the weeks prior to, and during, migration to the spawning grounds. In addition to the development of the kype, a large depression forms in the two halves of the premaxilla in the upper jaw, allowing the kype to fit into the premaxilla when the mouth is closed.^[3]

The kype functions as a secondary sexual characteristic and influences the formation of dominance hierarchies at the spawning grounds. The size of the kype is believed to determine male spawning frequency.

^ "Kype". FishBase. Retrieved April 26, 2016.
^ Cite error: The named reference Jarvi was invoked but never defined (see the help page).
^ Cite error: The named reference Witten was invoked but never defined (see the help page).

[Fishbase-1] "Kype". FishBase. Retrieved April 26, 2016.

[Jarvi-2] Cite error: The named reference Jarvi was invoked but never defined (see the help page).

[Witten-3] Cite error: The named reference Witten was invoked but never defined (see the help page).

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