Origin and development of the tergotrochanteral muscle in Chironomus (Diptera: Nematocera).
The origin and the development of the tubular tergo-trochanteral muscle (TTD) was studied by light and electron microscopy in Chironomus (Diptera: Nematocera). Unlike the flight muscles, the TTD was found to develop from myoblasts located around a larval axon, without contribution from a larval muscle. The myoblasts fuse together to form myotubes. Innervation of the TTD arises from the larval axon. The myotubes send out sarcoplasmic extensions towards the axon branches issued from the larval axon. The first differentiated synapses are described. The TTD begins to grow later than the flight muscles. The implications of this developmental lag are discussed.
Lebart-Pedebas
M C
MC
Université P. et M. Curie, Institut des Neurosciences, Département de Cytologie, 7 Quai Saint Bernard, Paris, France.