Radiolarians with "prunoid" morphologies (here defined as spumellarians with distinct external, generally ellipsoidal shells, usually bearing a pylome and having a lithelid, pylonid or spongy internal structure) are very common in polar Neogene sediments. Use of these taxa would improve resolution in Antarctic Neogene biostratigraphic and paleoceanographic studies significantly, but the taxonomy of prunoids is poorly known. This paper reviews the existing literature of generic names commonly used for prunoids, mostly dating from the nineteenth century. With the exception of Larcopyle Dreyer 1889, these names are either assigned to other, non-prunoid groups or are considered to be nomina dubia. Fourteen species, subspecies or varieties--most of them new--of Larcopyle from Antarctic Neogene sediments are described, illustrated with full plates and stratigraphic range data are provided: L. augusti n. sp., L. buetschlii Dreyer, 1889, L. eccentricum n. sp., L. hayesi Chen, 1975 hayesi n. variety, L. h. irregularis n. variety, L. labryinthusa n. sp., L. nebulum n. sp., L. peregrinator n. sp., L. polyacantha (Campbell & Clark 1944) n. comb. polyacantha n. subsp., L. p. titan n. subsp., L. p. amplissima n. subsp., L. titan (Campbell & Clark, 1944) n. comb., L. pylomaticus (Riedel, 1958) n. comb. and L. weddellium n. sp. J. Micropalaeontol. 24(2): 97-121, October 2005.