Movie 3

Opening reaction of the inner valve lids of the mesothoracic spiracle on a tactile stimulus (filter trichomes are partly removed). The opening is quicker than the closing. Opening starts from ventral and closing starts from dorsal.

Structure of the thoracic spiracular valves and their contribution to unidirectional gas exchange in flying blowflies Calliphora vicina

Lutz T. Wasserthal, and Anja S. Fröhlich

Journal of Experimental Biology 2017. 220:208-219; doi: 10.1242/jeb.149013