In males, the anal fin is shaped into a grooved, rod-shaped organ called a gonopodium used to deliver sperm to females.
12.
Male goodeids like the redtail splitfin have a notched anal fin that gives the fish the name " splitfin ", instead of the gonopodium of poeciliids.
13.
:In the guppy, the male's anal fin is folded to form a gonopodium through which sperm is egected directly into the female, who bears live young.
14.
The male has specialized anal rays which are greatly elongated and fused into a tube called a gonopodium associated with the sperm duct which he uses as an intromittent organ to deliver sperm to the female.
15.
""'Xiphophorus " "'is a genus of euryhaline and freshwater fishes in the family Poeciliidae of Greek words ????? ( dagger ) and ????? ( bearer ), referring to the gonopodium.
16.
Male guppies ( " Poecilia reticulata " ) have been observed to forcefully copulate with females by trying to insert their gonopodium ( male sex organ ) into female s genital pores, whether or not they are accepting.
17.
This is main distinguishing feature between fish of the genus " Neoheterandria " and fish of the genus " Xenophallus ", whose males have gonopodia that project either to the right or to the left . Unlike some male livebearer, which court the females they wish to breed with, male " Neoheterandria elegans " copulate by thrusting his gonopodium at the female's vent.
