I have people get these two beetles confused all the time, so I took a picture of them together so everyone could see the difference. In the photo, the Hercules beetle is the one on top. Most of the time people think the Hercules beetle is the Rhinoceros beetle. The Rhinoceros beetle’s horn is a little harder to notice and is not as large as the Hercules beetle. From the side, the Rhinoceros beetle’s horn looks very much like the head and horns of a Rhinoceros. The side view of the Hercules beetle looks a lot like the shape of a bottle or can opener. Both of these beetles only have the horns on the male of the species. Another difference is the Rhino beetle adults do not feed, while the Hercules beetle feeds on the sap of trees.