The life cycles of Philonema spp. resemble those of other dracunculoids (Brackett 1938; Furuyama 1934; Moorthy 1938; Thomas 1929) in the requirement of a copepod intermediate host and in its initial development in the connective tissues of the definitive host.

Life Cycle Example: P. conorhynchi, a parasite of the body cavity of the salmon host.:
The female nematodes are fully grown and gravid with fully developed first-stage larvae when thc salmon spawn. The nematodes are probably passed out with the fish eggs into the redd (a depression in the river or lake bottom gravel created by the upstroke of the female salmon's body and tail).  After about 1 minute in the river or lake water,  the female nematodes burst, liberating many thousands of larvae. The  larvae tend to remain in suspension which makes them readily available as food for copepods, Cyclops bicuspidatus, their intermediate host in which they become infective. The copepods are the main food supply for young samon which hatched from the eggs deposited in the redd. Infection of the young salmon occurs mainly in January and February in Canada, and the young salmon have accumulated a substantial nematode burden by April when they migrate to the sea. The nematode larvae infect the swim bladder of the fish (Platzer and Adams, 1967)..