On the taxonomy of the Lepidonotothen squamifrons group (Pisces, Perciformes, Notothenioidei)

The Lepidonotothen squamifrons group has been described to be comprised of 3 species: L squamifrons (Günther, 1880). L kempi (Norman, 1937) and L macrophthalma (Norman, 1937). All 3 species closely resemble each other and morphological and meristic characters utilized to distinguish between species are overlapping. Enzyme electrophoresis of enzyme polymorph isms has been applied to specimens morphologically recognized as L squamifrons and L kempi from various localities in the Scotia Arc region and the Kerguelen Islands to assist in clarifying their taxonomic status. Results suggest that both 'species' represent only populations of one species. Evidence is presented that the third species of the group, L macrophthalma, may also be identical with L squamifrons and that the L squamifrons 'group' is comprised of only one species, Lepidonotothen squamifrons (Günther, 1880). We found no statistically significant difference in allele frequencies between specimens from geographically isolated shelf areas of the Scotia Arc. This does not necessarily mean that the Scotia Arc region is inhabited by a single population but suggests some gene flow between shelf areas via larval drift for which evidence exists.