Наң қоректі қоңыздар: түрлері мен экологиялық ролі

Subfamily of beetles

The scarab beetle subfamily Scarabaeinae consists of species collectively called true dung beetles (there are also dung beetles in other subfamilies and families). 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 (telecoprids), dwellers (endocoprids) and tunnelers (paracoprids). 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.

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

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. A decline in dung beetle diversity associated with the conversion of native forests to open pastures is known to occur. However, some species are able to utilize dung in open pasture conditions. Tunneler species are able to utilize dung in less optimal condition because they tunnel beneath the dung and utilize it from bottom up. As desiccation occurs on the top of the dung pad, the middle and lower regions may still be suitable for the dung beetle. Also, smaller species are able to survive in such conditions as they require less dung. Larger beetles require larger amounts of dung which may not be available due to the fast desiccation of the dung pads in these conditions. Soil hardness and dryness negatively affect the tunnelers. Species able to tolerate open pasture conditions were extremely abundant. The reduction in the number of dung beetles affected the efficiency of their ecological roles and it was found that dung removal and burial declined. Dung removal and burial by dung beetles result in ecological benefits such as soil aeration and fertilization. These benefits lead to improved nutrient cycling and uptake by plants, increase in pasture quality, biological control of pest flies and intestinal parasites and secondary seed dispersal. Therefore, their role in the ecosystem is essential.

The subfamily is split into about 12 extant tribes. These can be grouped by their distribution, though the present classification is expected to require major revision based on recent phylogenetic analyses.