A pyrophile or pyrophilic/pyrophilous insect is an

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

which has evolved to rely upon

fire ecology Fire ecology is a scientific discipline concerned with the effects of fire on natural ecosystems. Many ecosystems, particularly prairie, savanna, chaparral and coniferous forests, have evolved with fire as an essential contributor to habitat vit ...

for important parts of their life cycle. Pyrophiles usually occur alongside and co-evolve with pyrophytes, the plant analog of a pyrophilic insect - those plants which rely upon natural fires as part of their lifecycle. These insects have evolved the ability to rapidly colonize environments after a

wildfire A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a ...

. Specialized olfactory organs sensitive to smoke and burnt plant volatiles guide adult insects to active wildfire sites, while in some species highly sensitive

thermal infrared A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example ...

receptors help them steer towards recently burned spots and avoid the dangers of actively burning areas. These infrared receptors are only known in insects from pyrophilous species and are thought to have evolved independently in at least four different genera. Many pyrophiles are somewhat to exceedingly rare outside of burn sites but become locally abundant within as little as hours after the start of a wildfire. Peak abundance may occur in the first one to two days of a fire, while it is still active, with numbers rapidly decreasing after a fire is extinguished. A pyrophilic lifestyle is extraordinarily uncommon amongst insects; of the over 1 million known insect species, only 0.005% are known to have a pyrophilous lifestyle. These include at least 30 species of beetles, 10 species of flies, 8 species of true bugs, and 1 species of moth. Flies of the genus '' Microsania'' are some of the most numerous and well-described pyrophilic insects. Others include buprestid beetles in the genera '' Melanophila'' and '' Merimna,''

ground beetle Ground beetles are a large, cosmopolitan distribution, cosmopolitan family (biology), family of beetles, the Carabidae, with more than 40,000 species worldwide, around 2,000 of which are found in North America and 2,700 in Europe. As of 2015, it ...

s in the genus '' Sericoda'', the cleroid beetle '' Acanthocnemus nigricans,'' and some species of

flat bug Aradidae is a family of true bugs (Heteroptera). Family members are commonly known as flat bugs due to their dorsoventrally flattened bodies. With few exceptions, these cryptic insects are of no economic importance. Aradids are 3 to 11 mm long ...

s in the genus '' Aradus''. Little is known about the broader ecosystem impacts and specific ecological interactions of pyrophilic insects. Various hypotheses attribute these insects' fire-loving adaptations as owing to the weakening of host plants creating greater food availability, the sterilization of the medium into which eggs are laid, and the elimination of competitive or predatory organisms.

Relationship with Humans

The European fire beetle '' Melanophila cuspidata'' has been used as an information filter to select which fire-released plant volatiles to target in the development of chemical sensors for early-warning fire alert systems in wood processing.

References

{{Insect-stub Insects