Stratton, 2005 has and extensive phylogenetic array of the genus which includes many macroscopic traits. Since the more recent additions to the ocreata group are defined primarily by behaviors, traditional means are often inconclusive. Also, there appears to be enough regional variation that finding an exact match in her chart may be impossible and finding the closest match may be as good as it gets. I spent a lot of time with two smaller spring species in Texas that are common in wooded floodplains. They are subtly separable by appearance, altitude within the floodplain, and about a month in season peak. There was no exact match for either in her chart but retrorsa and rovneri came closest. Both species share a minimal amount of sexual dimorphism. The main point I'd like to make is that extensive knowledge of local populations is important.