In nomenclature the word homonym is used for identical but independently proposed names for the same or different taxa. For exampe: Ochromyia Lehrer, 2005 is a homonym of Ochromyia Macquart, 1835. As a rule, the junior (more recent) name (in this case Ochromyia Lehrer, 2005) is invalid.
Tried to attach an image to a forum post. jpg, 32kB, 72dpi, no blanks, ... File name is correctly displayed, but when I click "Preview Thread" it just vanishes. Help!