hexapedal

A hexapod is an arthropod with six legs. This characteristic feature is shared by insects, which are the most well-known group of hexapods, and also by the Entognatha, a class of small, wingless arthropods that were formerly considered insects. The term "hexapod" comes from the Greek words "hex" meaning six and "podos" meaning foot.

The six legs of a hexapod are typically attached to the thorax, with two legs on each of the three thoracic segments. This arrangement allows for efficient locomotion and stability. In insects, the wings, if present, are also attached to the thorax. The body of a hexapod is generally divided into three main segments: the head, the thorax, and the abdomen. The head bears the mouthparts, antennae, and eyes, while the thorax is the primary locomotory segment. The abdomen typically contains the reproductive and digestive organs.

While insects are the dominant group of hexapods, there are other less familiar groups. Collembola (springtails), Protura (proturans), and Diplura (diplurans) are all hexapods that are distinct from insects, although they are often studied alongside them due to their superficial similarities. These groups are characterized by their small size and often live in soil or leaf litter.

The evolutionary success of hexapods, particularly insects, is attributed to a combination of factors including their exoskeletons, which provide protection and support, their ability to fly, and their diverse mouthparts, which allow them to exploit a wide range of food sources. Their relatively short generation times and high reproductive rates also contribute to their widespread distribution and abundance.