The specific name nitida was originally used by Desmarest (1817) with resepct to a fossil specimen (no longer extant) and the genus Goneplax. In 1822 he shifted this fossil to the genus Gelasmius as well as applying it to an extant species. H. Milne Edwards (1837) cites Desmarest's fossil and use of the name with Gelasmius.
Dana (1851) apparently independently used the identical name for a fiddler crab from Fiji (specimen no longer extant). Dana's use of the name is the one subsequently followed by most authors for the century following its publication, including H. Milne Edwards (1852) who referenced Dana and made no mention of the Desmarest fossil. Today Dana's species is known as Uca excisa Nobili, 1906.
As things currently stand, Gelasimus nitida Dana, 1851, is considered a junior homonym of Gonexplax nitida Desmarest, 1817. If Desmaret's fossil specimen were found and turned out not to be a fiddler crab, then Dana's use of nitida would no longer be a homonym and would have priority over excisa.