A spermatophore or sperm ampulla is a capsule or mass created by
males of various animal species, containing spermatozoa and
transferred in entirety to the female's ovipore during
copulation. It may contain nourishment for the female, in which
case it is called a nuptial gift, although in many species the
"gift" provides little nutrient value (one group in which it
usually is nutritious are the bush crickets). The alternative
hypothesis of its usefulness is that the process of eating the
spermatophore prevents the female from subsequent copulation,
thereby giving the male's sperm more time to fertilize.
Spermatophores are the norm in arachnids. In various insects,
such as bush crickets, the spermatophore is often surrounded by
a proteonaceous spermatophylax. The function of the
spermatophylax is to cause the female to relinquish some of her
control over the insemination process allowing full sperm
transfer from the spermatophore. Some vertebrates also reproduce
via spermatophores. Males of many salamander and