Motor Neurons of the Indirect Flight Muscles of Dysdercus fulvoniger1,2

Abstract

The indirect flight muscles of D. fulvoniger (Hemiptera: Pyrrhocoridae) consist of paired dorsal longitudinal, dorsal oblique, and dorsoventral muscles. These are innervated by branches of nerves coming from the mesothoracic component of the pterothoracic ganglion. Five motor neurons are associated with each dorsal longitudinal muscle; the somata of 4 of these are ipsilateral in the prothoracic ganglion and one is contralateral in the mesothoracic region of the pterothoracic ganglion. The somata of the 3 motor neurons of the dorsal oblique muscle are ipsilateral in the prothoracic ganglion. Each dorsoventral muscle is apparently innervated by 2 neurons and their somata are ipsilateral in the mesothoracic ganglionic region. In addition, a dorsal unpaired median neuron in the pterothoracic ganglion is associated with the dorsal longitudinal muscle, but its function is unknown. There are no conspicuous changes in the appearance of the flight motor neurons following the histolysis of the flight muscles.