Gonopodium
The term gonopodium ( Greek gon "procreation" or gonos "birth", "descent" and podion " little feet"; plural gonopods) is a general term for a transformed extremity that is used for copulation. The term is common both with different groups of the arthropods (Arthropoda), such as the crustaceans (Crustacea) and the Myriapoda , and with bone and cartilaginous fish . In the arthropods are in the gonopods to the converted first pair of legs of the abdomen (abdomen).
Gonopodia in bony fish
The gonopodium or the copulation fin of fish is an organ that consists of the transformed rays of the anal fin ( anal ). With this organ, the fertilization of the germ cells in the body of the female and thus live birth is possible. One finds this among other things in viviparous tooth carps . The gonopodium ends in most species with a more or less distinct hook or claw.
In other species one finds similar organs with the same task, such as the andropodium in the half- beaked pike ( Hemirhamphodon ) or the highland carfish (Goodeidae).
During mating , the male briefly inserts the gonopodium into the genital opening of the female. With the hook or the claw, it can hold on better during the transfer of the sperm in order to increase the success of fertilization.
literature
- Alfonso L. Rojo: Dictionary of Evolutionary Fish Osteology . CRC Press, Boca Raton (Florida) 2018, p. 88 (on Google Books )
- Margaret E. Brown: The Physiology of Fishes: Behavior . Academic Press, New York City 1957, p. 292 ff. (On Google Books )
Individual evidence
- ↑ Volker Blüm: Comparative reproductive biology of vertebrates . Springer-Verlag, Berlin / Heidelberg 1985, p. 73 ff. (On Google Books )
- ^ Anne E. Houde: Sex, Color, and Mate Choice in Guppies . Princeton University Press, Princeton (New Jersey) 1997, p. 32 ff. (On Google Books )