Cuticular plasticization induced by copulatory stimuli in female Haemaphysalis longicornis (Acari:Ixodidae).

Partially engorged adult female ticks, Haemaphysalis longicornis Neumann, received complete, incomplete, or no copulatory stimuli. Subsequently, they were inflated with physiological saline by injection into the haemocoel. Ticks that copulated received both preinseminational and inseminational stimuli and increased their body volume > 10-fold. Ticks that incompletely copulated received only preinseminational stimuli and expanded slightly, whereas ticks that did not copulate did not expand. These results show that the soft integument of H. longicornis only expanded after complete copulation. Therefore, copulatory stimuli induced cuticular plasticization.