The scarab beetle subfamily Scarabaeinae consists of species collectively called true dung beetles. Most of the beetles of this subfamily feed exclusively on dung. However, some may feed on decomposing matter including carrion, decaying fruits and fungi. Dung beetles can be placed into three structural guilds based on their method of dung processing namely rollers, dwellers and tunnelers Dung removal and burial by dung beetles result in ecological benefits such as soil aeration and fertilization; improved nutrient cycling and uptake by plants, increase in Pasture quality, biological control of pest flies and intestinal parasites and secondary seed dispersal. Well-known members include the genera Scarabaeus and Sisyphus, and Phanaeus vindex. Description Adult dung beetles have modified mouth parts which are adapted to feeding on dung. The clypeus is expanded and covers the mouth parts. The elytra, which cover the wings, expose the pygidium. They also have a space between their middle legs to allow for manipulation of the dung. Dung beetles can be large beetles of a few inches in size to small beetles which are only a few millimeters in size Guilds Dung beetles are classified into groups based on their method of processing the dung. Rollers are beetles that construct balls of dung from the main food source. They roll away this ball from the position of the original food source and use the dung for feeding or for reproduction. Tunnelers are beetles that dig tunnels beneath the food source creating nests. They relocate food into their nest for reproduction and feeding. Lastly, dwellers are beetles that live and reproduce inside the food source rarely creating nests. Reproduction Pheromones are thought to aid in dung beetle reproduction. Dung beetles copulate after which both parents dig a tunnel to lay the eggs. This tunnel may have different branches leading to varying egg chambers or may not be branched depending on species. Both parents take dung inside the tunnels in the form of brood balls and the females lay the egg inside the dung. When the larva hatches it feeds on the surrounding dung and forms a pupa undergoing several instars. After this stage the pupa hatches and the newly formed adult evades the tunnel and searches for a fresh dung supply for feeding. After approximately 2 weeks the new adult beetle will be able to reproduce. Ecology Dung beetle communities are dependent on vegetation and presence of mammalian dung resource.