any of approximately 15 species of insects found only in certain regions of Africa, the common name of which is derived from their stout appearance and predatory behaviour. These insects have modified raptorial legs that give them the ability to grasp their prey. While some species attack and capture prey equal to their own size, other species are slow-moving and capture smaller prey. Many of these insects are nocturnal, emerging only at night to hunt and feed. Most species are light to reddish brown, although some species may be light green or dark brown, and others may have black or red spots. The gladiator bugs superficially resemble mantids (family Mantidae) and walkingsticks (family Phasmatidae), although they are easily distinguished by their unique long, thin antennae and their tendency to hold the last segment of their legs up in the air, making them appear as though they are walking on their heels (hence the alternate name heelwalker). Adults of known species range in overall body length from a minimum of 5.8 mm (0.2 inch) in Adicophasma spinosa (known from Baltic amber) to 32.0 mm (1.3 inch) in Tyrannophasma gladiator, the largest of the gladiator bugs. All extant species occur in the hot, dry environments of Tanzania in East Africa or the Karoo-Namib region of southern Africa.
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