The generation and propagation of double waves in mosquito (Aedes notoscriptus) sperm‐tails

In the mosquito Aedes notoscriptus nine accessory tubules develop from the doublets of the axoneme whose single central fibre forms late in spermiogenesis. The 9 + 9 + 1 mosquito sperm‐tail propagates two waves of differing frequency and amplitude. The structural basis for the movement is of interest. Mosquito sperm were demembranated until all movement ceased and were reactivated with a solution containing adenosine triphosphate (ATP). They immediately moved in a normal fashion. Like untreated sperm, they always propagated double waves. This indicates that the plasma membrane does not control the double wave. After sonicating sperm treated as above, the high‐frequency, low‐amplitude waves sometimes propagated alone beyond a damaged region of sperm‐tail, whereas the large‐amplitude, low‐frequency waves never propagated alone beyond a damaged region. This suggests that the latter waves are generated by an anterior site, possibly the centriole or centriole adjunct. The structure that propagates the large amplitude wave is not known; possibly the accessory tubules may slide against the axonemal doublets. Any region of the sperm‐tail is capable of generating and propagating the low‐amplitude, high‐frequency wave, for which the structure responsible is probably the axoneme.