What is the largest beetle species by body length?

What is the largest beetle species by body length? The titan beetle, Titanus giganteus, is the standard answer when length means the beetle's body alone. Reliable measurements place the largest documented individuals at about 16.7 centimeters, or 6.5 inches.

This enormous longhorn beetle lives in tropical South American rainforests, including parts of Brazil, French Guiana, Colombia, Ecuador, Peru, and the Guianas. Its huge mandibles and sharp thoracic spines provide formidable defenses, although its adult life lasts only a few weeks.

The titan beetle's size record is easy to confuse with other beetle records. The Hercules beetle can become longer if its large horn is included, while the sabertooth longhorn beetle can exceed the titan beetle in total length when its oversized male mandibles are counted. Standard body-length measurements exclude such horns and jaws, which is why the titan beetle remains the canonical answer for body length.

Adults of this species apparently do not feed regularly; the energy gained as larvae from decaying wood helps sustain the short-lived adult stage.