T. Harada et al., MIGRATORY SYNDROME IN THE WATER STRIDER AQUARIUS-PALUDUM (HETEROPTERA, GERRIDAE) REARED IN HIGH VERSUS LOW NYMPHAL DENSITIES, European journal of entomology, 94(4), 1997, pp. 445-452
The effect of crowding in nymphal stage on the induction of developmen
t of macropterous adults with high flight ability was studied in the l
aboratory in the water strider Aquarius paludum. High density induced
a higher proportion of macropterous morphs than low density. No brachy
pterous adults developed flight muscles in either experimental density
. When kept under high density, about 80% of adults kept indirect flig
ht muscles for 25-30 days after adult emergence, whereas only about 50
% or 60% of females and males, respectively, retained theirs when grow
n under low density. The remaining adults histolysed indirect flight m
uscles in both groups. Development during the fourth and fifth instars
only under high density may induce a higher proportion of macropterou
s adults than those under low density.