A new species of the genus Omicrus Sharp, 1879, O. vanini spec. nov., from the Santa Catarina State in South Brazil is described and illustrated. The species is very similar to few other Brazilian species, but may be clearly diagnosed by the combination of external characters and male genitalia.
All specimens of the new species were collected from the detritus accumulated in the rosettes of the ground-growing bromeliads of the genera Hohenbergia, Nidularium and Canistrum. It is the second known bromeliad-inhabiting species of the genus Omicrus.