Scolopendra heros, commonly known as the Arizona desert centipede, giant desert centipede, giant Sonoran centipede, Texas black-tailed centipede, Texas redheaded centipede, and giant redheaded centipede, is a species of North American centipede found in the Southwestern United States and Northern Mexico.
Description
right|thumb|S. heros var. castaneiceps found in Oklahoma, with red head and black body
S. heros is the largest centipede in North America. It has an average length of , but can reach up to in the wild, and even longer in captivity.
It is aposematically colored, to warn off potential predators, and a number of color variants are known in the species.
Hunting and diet
S. heros is primarily a nocturnal predator and hunts invertebrates and small vertebrates, including rodents, reptiles, and amphibians. It is capable of reaching into the air to grab small flying insects. The centipede uses its venom to subdue prey.
Life cycle
S. heros hatch from eggs. As they grow and mature, like all arthropods they shed and molt away their exoskeleton. Each time they molt they enter a new stage of its life cycle called an instar. Like all Scolopendromorph centipedes, the number of segments they possess remains the same throughout their life. S. heros is a slow-growing species capable of living over a decade.
Venom
The venom of S. heros is similar in composition to the venom of other Scolopendra species, including components such as serotonin, histamine, lipids, proteins (including cardiotoxic proteins and enzymes such as hemolytic phospholipase A), and other substances. The mixture is known to act as a cytolysin, compromising cellular membranes and rupturing cells. S. heros venom also contains toxins targeted to its prey: one toxin numbs the nervous system of insects, rendering them unable to sense or escape, while another toxin interferes with the autonomic nervous system of vertebrates to make small vertebrates easier to subdue and devour. The exact effects and makeup of the venom have not been thoroughly evaluated, in part because it is difficult to extract in significant quantities and quickly deteriorates when processed. For humans, a bite from S. heros usually causes sharp, searing, local pain and swelling, but has never caused any confirmed deaths.