S. Mpuru et al., Effect of age and sex on the production of internal and external hydrocarbons and pheromones in the housefly, Musca domestica, INSEC BIO M, 31(2), 2001, pp. 139-155
The epicuticular and internal waxes of male and female houseflies were exam
ined by capillary gas chromatography-mass spectrometry at closely timed int
ervals from emergence until day-6 of adulthood. New components identified i
ncluded tricosan-10-one, 9,10-epoxyheptacosane, heptacosen-12-one, a series
of odd-carbon numbered dienes from C31 to C39, several positional isomers
of monoenes including (Z)-9- and 7-pentacosene and a number of methyl- and
dimethylalkanes, (Z)-9-tricosene appears in internal lipids prior to appear
ing on the surface of the insect, suggesting that it is transported in the
hemolymph to its site of deposition on the epicuticle. The large increases
in the amount of (Z)-9-tricosene in females from day-2 until day-6 is compe
nsated for by a concomitant decrease in (Z)-9-heptacosene. The C23 epoxide
and ketone only appear in females after the production of (Z)-9-tricosene i
s induced, and are only abundant in epicuticular waxes, suggesting they are
formed after (Z)-9-tricosene is transported to the cells which are involve
d in taking them to the surface of the insect. Mathematical analysis indica
ted that the time shift between internal production and external accumulati
on in females is more than 24 h. The divergence between male and female lip
id production occurs at an early stage, when insects are less than one day
old. (C) 2001 Published by Elsevier Science Ltd.