Dung Beetle.

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Dung Beetle

Onthophagus taurus

Kingdom: Animalia

Phylum: Arthropoda

Class: Insecta

Order: Coleoptera

Family: Scarabaeidae

Genus: Onthophagus

Species: Taurus

General Characteristics

According to Northern Flagship Institute (http://www.nfi.co.za/coleoptera/

beetles/dung beetles.htm), dung beetles are invertebrate insects (order: coleoptera, family: scarabaeidae). They vary in size from two to thirty millimeters in body length. They are composed of three body segments - the head, the prothorax, and the abdomen. They have a hard outside cuticle and folded wings that cover the upper surface of the abdomen. These are themselves covered by elytra (wing coverings).

The wings of these beetles are transparent to whitish in color and are only visible when in flight (due to the elytra). Like other insects, dung beetles have six legs, an exoskeleton, and a pair of antennae. The legs, though, are specialized for gathering and manipulating feces. They also have specialized mouth parts for ingestion of liquefied material.

Distribution

Dung beetles comprise thousands of species in the family Scarabaeoidea.

They are found wherever there is feces. Different groups of dung beetles are restricted to specific geographic areas, habitats, and even specific kinds of excrement (Simmons, 1999).

Form

Adult dung beetles have mouth parts which are specially adapted to feed on liquefied material and can breakdown a dung pad very efficiently by burying the dung underground to use when breeding (Shafiei, 2001).

Males in the Onthophagus taurus beetle (Coleoptera: Scarabaeidae) have elaborate horns. Male horn expression is facultative, and is regulated by a developmental threshold where males growing larger than the threshold size produce horns, and males remaining smaller than this size do not (Hunt, 2001).

Beetle horns are exaggerated extensions of exoskeleton, expressed only in males. They are used in combat over access to females. They constitute a significant investment for the developing animal. Horn development does not begin until the...