Fifty specimens of Harpagifer antarcticus Nybelin, 1947 caught off
King George Island in Admiralty Bay (44) and off Elephant Island (6), were
examined for endoparasitic worms. Fifteen or sixteen species and larval
forms were found, including three species of Digenea (Macvicaria
georgiana, Genolinea bowersi and Gonocerca phycidis),
four forms of larval Cestoda (three tetraphyllidean cercoids and
diphyllobothriid plerocercoid), five species of
Acanthocephala (Aspersentis megarhynchus, Metacanthocephalus
dalmori, Corynosoma arctocephali cystacanth, C.
hamanni cystacanth and C. pseudohamanni
cystacanth) and three or four species of Nematoda, Ascarophis
nototheniae, Pseudoterranova decipiens third stage larva
(L3) and Contracaecum sp. L3 = ?C. osculatum and
Only some of the specimens of the two digenean species, M. georgiana and G. bowersi, were fully mature (containing eggs). No one form is specific for Harpagifer, eight have not previously been reported from H. antarcticus. The total prevalence of infection was 68% with a maximum intensity 19 worms. The most numerous parasite in Admiralty Bay was G. bowersi (67 specimens) occurring with a prevalence of 23%; A. megarhynchus was less numerous (19 specimens), but occurred with a higher prevalence, 25%. A list of internal parasitic worms of H. antarcticus (according to present and literature data, probably 17 forms) is compared with that of Notothenia coriiceps occurring in the similar (partly the same) environment at King George Island (27 forms); this is 63% of forms recorded in H. antarcticus. All parasites of H. antarcticus occur in N. coriiceps. A list of parasitic worms recorded in three harpagiferid species is given. The role of harpagiferids as intermediate or paratenic hosts of parasitic worms appears to be more important than a role as definitive hosts.