Insect morphology least three different positions: prognathous, opisthognathous, and hypognathous. In species with prognathous articulation, the head is positioned vertically aligned with the body, such as species of Formicidae; while in a hypognathous type, the head is aligned horizontally adjacent to the body. An opisthognathous head is positioned diagonally, such as species of Blattodea and some Coleoptera. The mouthparts vary greatly between insects of different orders, but the two main functional groups are mandibulate and haustellate. Haustellate mouthparts are used for sucking liquids and can be further classified by the presence of stylets, which include piercing-sucking, sponging, and siphoning. The stylets are
Insect thermoregulation Insect thermoregulation Insect thermoregulation is the process whereby insects maintain body temperatures within certain boundaries. Insects have traditionally been considered as "poikilotherms" (animals in which body temperature is variable and dependent on ambient temperature) as opposed to being "homeothermic" (animals which maintain a stable internal body temperature regardless of external influences). However, the term "temperature regulation", or "thermoregulation", is currently used to describe the ability of insects and other animals to maintain a stable temperature (either above or below ambient temperature), at least in a portion of their bodies by physiological or behavioral means. While many insects are "ectotherms" (animals