Long-horned Cactus Beetle, Moneilema gigas

The cactus longhorn beetle resembles the foul smelling and unrelated Eleodes (darkling beetles), both in appearance and behavior. Tests have shown that species of Moneilema behave in a way similar to Eleodes when faced with predators such as lizards, wood rats, and skunks. Although these cactus longhorn beetles can be found on the ground wandering about, their preferred spiny host, the cholla, also affords them a considerable degree of protection. This cactus is well known for its long, extremely sharp & barbed spines, between which the adults rest during the day. One requires long tongs to remove them to avoid being spired by the cactus. Adult Moneilema feed on the softer, more succulent portions of the cactus. The female lays her eggs at the base of the cactus inside an earthen case. Upon hatching, the larvae bore into the roots and stems of the cactus to feed. Their boring activities above ground are conspicuous, as they expel tar-like excrement and fluid from the wounds created by their feeding activities.

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