The Male Reproductive System

Male nematodes also may have one gonad, called monorchic and this may be reflexed anteriorly (A, B). A diorchic male system has two gonads, typically oriented in opposing directions, but joining at a shared duct (6C).

Fig. 6. Basic orientation of male reproductive tract. A. Monorchic (one gonad) B. Monorchic and reflexed. C. Dicorchic (two gonads).

The male reproductive system is equipped with complex accessory structures for mating. These include a pair of cuticularized spicules which are protrusible by a complex set of muscles (A). Together the spicules form a conduit, visible in cross section, thorugh which sperm pass (B). The spicules move in a channel that posteriorly may have a heavy cuticular lining, the gubernaculum.

Click here to see some clips of male tails.

Fig. 8. Male copulatory stuctures. A. Lateral view. B. Ventral cross section showing the relationship of spicules to the gubernaculum. A is redrawn from Coomans,1962.