ANTENNAL MUSCLES AND FAST ANTENNAL MOVEMENTS IN ANTS

The antennal movements of eight ant species (subfamilies Ponerinae, My rmicinae, and Formicinae) are examined by high-frequency videography. They show a wide range of antennal velocities which is generated by an tennal muscles composed of particularly diverse muscle fibers. Fiber d iameter, sarcomere length and histochemically assessed myosin ATPase a ctivity suggest that some thin fibers are fairly slow, while the bulk of antennal muscle fibers show intermediate or fast properties. These morphological, properties correlate with the antennal movement velocit ies measured for the respective species. Based on their morphology, th e fibers that generate the fast antennal retraction in some trap-jaw a nts appear particularly fast and comprise the shortest sarcomeres yet described (1.1 mu m).