The fine structure of developing sarcoplasmic reticulum and tracheoles of the flight muscle of Locusta migratoria L. (Orthopetra, Acrididae)‎

الملخص EN

The present study is concerned with developmental changes of sarcoplasmic reticulum (SR) and tracheoles of Locusta migratoria flight during the first week after post ecdysis.

The relative volume of the SR and T-system decreased with age.

The decrease was associated with the formation of dyadic junctions and the separation of adjacent myofibrils by sheet of SR.

In the first few days of post ecdysis, dyadic junctions are situated near the Z-bands or at an oblique angle to the adjacent myofibrilis.

In contrast, the dyadic junctions of fully developed flight muscles are situated in the region of the A-bands and run parallel to the myofibrils.

The distribution of the SR and T-system was affected by the penetration of tracheoles into the muscle fibre.

Muscle tracheation was more or less fully developed by the third day of post ecdysis.

The relative volume of tracheoles decreased with age after the third day of post ecdysis.