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Twenty fishes Lepidonotothen macrophthalma (Norman) caught at the North Scotia Ridge were examined. They harboured four digenean species - the opecoelids, Macvicaria antarctica (Kovalyova et Gaevskaya, 1974) and M. skorai sp. n., the lepocreadiid, Neolepidapedon magnatestis (Gaevskaya et Kovalyova, 1976), and the unnamed hemiurid (presently not described). The total prevalence of Digenea (four species) was 55%, intensity range 2-21 and relative density 3.50. M. skorai sp. n., which occurs sympatrically with M. antarctica, is described. M. skorai sp. n. is characterised by the cirrus sac reaching posterior to the ventral sucker, sucker ratio based on mean diameter 1:1.50-1.92 (mean 1.74), oblique arrangement of testes, egg length 0.043-0.055 mm (usually 0.045-0.051 mm) and testes usually obscured dorsally by vitelline follicles. This species is compared with all Antarctic and sub-Antarctic Macvicaria occurring in Perciformes. N. magnatestis is redescribed from the nototheniids L. macrophthalma and L. squamifrons (Gunther) and compared with N. trematomi Prudhoe et Bray, 1973. Specimens previously reported by Zdzitowiecki (1990b) as N. magnatestis collected from Trematomus hansoni and T. bernacchii in the South Shetland Islands area and from Dissostichus eleginoides collected off the Shag Rocks (South Georgia area) are considered N. trematomi.