 Rauhut & Carrano (2016) listed several features which could be used to diagnose Elaphrosaurinae.Elaphrosaurine cervical vertebrae are amphicoelous, meaning that both their front and rear faces are concave, particularly the front face which is quite strongly concave.While strongly concave front faces are common among many archosaurs, they are quite rare in all but the most basal theropods.