Studies on Gyrocotyle rugosa Diesing, 1850, A Cestodarian Parasite of the Elephant Fish, Callorhynchus milii
Gyrocotyle rugosa is a common parasite of the elephant fish in New Zealand, G. urna also occurs in the elephant fish, but less commonly. A description is given of the adult G. rugosa and its lycophore larva. Very small postlarval stages are common in the mucus scraped from the spiral valve of the host, although not more than six adults were found in one host.
Eggs of G. rugosa taken from the uterus of adult worms hatch almost immediately in sea water. They did not infect a snail (Buccinulum), a bivalve (Aulacomya), or a hermit crab. They do penetrate, in large numbers, scrapings of mucus from the spiral valve of an elephant fish. They also penetrate pieces of the wall of the spiral valve, usually entering the muscular layers, and may reach and enter blood vessels within an hour.