Spray hole
The injection hole or suction hole ( Latin: Spiraculum = "air hole") is a converted gill opening in most sharks and all rays , which lies behind or below the animals' eyes. It is used to suck in respiratory water and guide it through a channel into the gills so that the oxygen it contains can be used for breathing .
Especially with the ground sharks and rays, which mostly live on the ground, the breathing water is almost exclusively absorbed through the spray holes, since otherwise it would consistently contain silt and sand due to the lower mouth . For this reason, the stingrays have the injection holes on the back, while the gill outlets are on the belly side.
Most lower bony fish also have a paired spiraculum , although not necessarily for inhalation, e.g. B. the sturgeon and the pike . (It usually contains a sense organ that is associated with hearing.) In real bony fish (Teleostei) it does not (“more”) occur.
The spiraculum of the frog is an unpaired gill hole on the belly or left side of the body of tadpoles .
literature
- Kuno Sch. Steuben , Gerhard Krefft: The sharks of the seven seas - species, way of catching and sporty catch . Paul Parey Verlag, Hamburg / Berlin 1989, ISBN 3-490-44314-4 .
- Lexicon of Biology. Volume 13, Spektrum Akademischer Verlag, Heidelberg 2004, ISBN 3-8274-0338-3 .