I don't know whether any hybids have been made with American species, but the South African Hypoxis parvula has been crossed with Rhodohypoxis baurii with success. The hybrids are correctly called Rhodoxis, though more commonly are still sold as "Rhodohypoxis hybrid" or similar. The best known ones which easily available over here in the UK are the "Hebron farm" series which have cultivar names such as 'Hebron Farm Biscuit', 'Hebron Farm Cerise' and 'Hebron Farn Red Eye'. I don't have pictures of any of these but a web search will turn up a few pictures. Paul Cumbleton Berkshire U.K. Zone 8