Male accessory secretions, their use and replenishment in Glossina (Diptera, Glossinidae)

Abstract

The male accessory glands of Glossina austeni Newst. contain an apical secretion-a dense, opaque, whitish secretion at the apical end of the gland, and a diffuse secretion-a bulkier, more mobile, translucent, whitish secretion occupying nearly all the remainder of the gland. There is also a plug of clear solidified accessory material preventing the outflow of secretions from the resting gland. By immersing the whole accessory gland in a saline medium at pH 2-2, and then transferring the specimen to distilled water, the apical secretion can be separated manually from the rest of the gland, as an apical body. Measurements of the apical body in virgin male flies show that the apical body increases in width according to the equation: Age = constant X width 2 -5 , but individual deviations from this relation were considerable. Immediately after mating the apical body is long and thin; recovery to approximately the resting condition is complete after 48 h, but, on average, mated males have thinner apical bodies than virgin males of the same age. The use of apical secretion measurements to assess mating frequency under field conditions might be possible if adequate samples of males were available.

Sexual receptivity and age in Glossina pallidipes Austen (Dipt., Glossinidae)

“…There was much individual variation in the development of apical bodies and it would be difficult to use apical body widths as a measure of male maturity. In G. m. morsitans , accessory gland secretions have been implicated in protecting sperm (P OLLOCK , 1974) and if re‐mating is truly rare in G. pallidipes (L EEGWATER VAN DER L INDEN and T IGGELMAN , 1984) then the accessory fluid may play a role in modifying female behaviour. The true role of accessory gland secretions in tsetse still needs to be determined.…”

“…Studies on the spermatophore formation in females and the changes in the accessory glands of males (apical body) after mating, suggested that the spermatophore precursor secretions are derived from male accessory glands (P OLLOCK , 1970). These observations suggested that measurements of the apical body width may be used to indicate the mating frequency of the males in the field (P OLLOCK , 1974), a phenomenon that could be important in monitoring mating in released sterile males.…”

The Effects of a Tsetse DNA Virus Infection on the Functions of the Male Accessory Reproductive Gland in the Host Fly Glossina morsitans centralis (Diptera; Glossinidae)

“…Late in the copulation period the sperm migrate from the spermatophore to the spermathecae [17]. Accessory gland diameter in G. morsitans males increases only after feeding, and this increase appears to be due to accumulation of accessory gland fluid [13]. The influence of blood meals and neurosecretion on the synthesis of accessory gland secretions in tsetse flies has been demonstrated [14], and a positive correlation between spermatophore formation and insemination in G. morsitans has also been shown [17], thus insemination can only occur with the agency of the spermatophore.…”

Some aspects of sexual receptivity and refractory behaviour in female Glossina morsitans morsitans Westwood

“…We have shown that the duration of copulation does not affect refractory behaviour once mating is between a sexually mature male and female. It has been shown that the development of the male accessory gland is dependent on the age of the fly (Pollock, 1974;Foster, 1976;Samaranayaka-Ramasamy, 1981). It has been shown that the development of the male accessory gland is dependent on the age of the fly (Pollock, 1974;Foster, 1976;Samaranayaka-Ramasamy, 1981).…”