The life cycle of the gyrocotylids is poorly understood. Like many marine parasites they are known mainly from their definitive hosts. If larval forms are found that might belong to that species, it can be difficult to confirm by the traditional route of experimental infection, since many marine hosts are difficult to rear parasite-free and maintain in captivity.
Gyrocotyle lives in the intestine of deep sea ratfish. Eggs are released and hatch to produce a lycophore larva. It is not known whether an intermediate host is required, or whether the lycophore simply penetrates or is eaten by another ratfish.