Two types: indirect and direct.
The indirect muscles
- do not directly effect wing
- attach to the tergum
- distort the thoracic box when contracted
- distortion transmits forces to the wing.
- two bundles of indirect muscles:
dorsolongitudinal (DLM)
dorsoventral (DVM)
- dorsolongitudinal span the length of the tergum
- dorsoventral extend from the tergum to the
sternum