O. gracilis may refer to: Obruchevichthys gracilis, an extinct tetrapod species from Latvia during the Late Devonian Oceanites gracilis, the Elliot's storm-petrel, a seabird species Oedipina gracilis, a salamander species found in Costa Rica and Panama Omphalotropis gracilis, a gastropod species endemic to Guam Ormosia gracilis, a legume species found only in Malaysia Oxidus gracilis, the "greenhouse millipede", a widely introduced millipede associated with agricultural areas worldwide Oxyopsis gracilis, the South American green mantis, a praying mantis species
See also Gracilis (disambiguation)