The Katydid Spermatophore (Orthoptera: Tettigoniidae): Male Nutritional Investment and its Fate in the Mated Female

Abstract

In the katydid Requena verticalis Walker. radioactively labelled protein hydrolysate fed to males is incorporated into various parts of the body, but is more concentrated in the reproductive accessory glands that produce the large spermatophore. The spermatophore consists of two parts, only one of which contains sperm. Both parts are eaten by the female after mating. Females mated to these males had high concentrations of label in their spermathecae; this was most probably derived from label in the storedejaculate. Label in other parts of the body is acquired mainly from nutrients in the spermatophore eaten by the female. Ovaries and immature eggs of females at 3 days post-mating had higher concentrations of male-donated proteins than had somatic tissues, but females at 9-13 days post-mating did not show this difference. However, the older females had developed mature ovarian (and thus unfertil- ized) eggs which did have higher concentrations of label.