Glowworm or glow-worm is the common name for various groups of insect

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

e and adult

larviform female Larviform female is a biological phenomenon occurring in some insect species, where the females in the adult stage of metamorphosis resemble the larvae to various degrees, while the male appears more morphologically adult (as imagoes). The resemblan ...

s that glow through

bioluminescence Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some b ...

. They include the European common glow-worm and other members of the

Lampyridae The Lampyridae are a family (biology), family of Elateroidea, elateroid beetles with more than 2,000 described species, many of which are bioluminescence, light-emitting. They are soft-bodied beetles commonly called fireflies, lightning bugs, ...

, but bioluminescence also occurs in the families

Elateridae Elateridae or click beetles (or "typical click beetles" to distinguish them from the related families Cerophytidae and Eucnemidae, which are also capable of clicking) are a family of beetles. Other names include elaters, snapping beetles, sp ...

Phengodidae The beetle family Phengodidae is known also as glowworm beetles, whose larvae are known as glowworms. The females and larvae have bioluminescence, bioluminescent organs. They occur throughout the New World from extreme southern Canada to Chile. ...

and

Rhagophthalmidae The Rhagophthalmidae are a family of beetles within the superfamily Elateroidea. Members of this beetle family have bioluminescent organs on the larvae, and sometimes adults, and are closely related to the Phengodidae (glowworm beetles), though ...

among

beetle Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

s; as well as members of the genera

Arachnocampa ''Arachnocampa'' is a genus of nine fungus gnat species which have a bioluminescent larval stage, akin to the larval stage of glowworm beetles. The species of ''Arachnocampa'' are endemic to Australia and New Zealand, dwelling in caves and gr ...

, Keroplatus and Orfelia among keroplatid fungus gnats.

Beetles

Four families of beetles are bioluminescent. The wingless

s and larvae of these bioluminescent species are usually known as "glowworms". Winged males may or may not also exhibit bioluminescence. Their light may be emitted as flashes or as a constant glow, and usually range in colour from green, yellow, to orange. The families are closely related, and are all members of the beetle superfamily,

Elateroidea The Elateroidea are a large superfamily of beetles. It contains the familiar click beetles, fireflies, and soldier beetles and their relatives. It consists of about 25,000 species. Description Elateroidea is a morphologically diverse group, i ...

. Phylogenetic analyses have indicated that bioluminescence may have a single evolutionary origin among the families Lampyridae, Phengodidae, and Rhagophthalmidae; but is likely to have arisen independently among Elateridae. * Family

– The click beetles. Of the estimated 10,000 species classified under this family, around 200 species from tropical regions of the Americas and some

Melanesia Melanesia (, ) is a subregion of Oceania in the southwestern Pacific Ocean. It extends from Indonesia's New Guinea in the west to Fiji in the east, and includes the Arafura Sea. The region includes the four independent countries of Fiji, Va ...

n islands are bioluminescent. All of them are members of the subfamily Pyrophorinae, except for one species, ''

Campyloxenus pyrothorax ''Campyloxenus'' is a bioluminescent genus of click beetles in the family Elateridae Elateridae or click beetles (or "typical click beetles" to distinguish them from the related families Cerophytidae and Eucnemidae, which are also capabl ...

'', which belongs to subfamily Campyloxeninae, and ''

Balgus schnusei ''Balgus'' is a genus of click beetle (family Elateridae). They are one of several genera in the family which contain at least one bioluminescent species. The genus was originally placed in the family Eucnemidae, later transferred to Throscidae ...

'', in Thylacosterninae. * Family

– True Fireflies. Contains around 2,000 species found throughout the world. Some "Glow worms" are in this family. * Family

– Usually known as glowworm beetles. Contains around 230 species

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the

New World The term ''New World'' is often used to mean the majority of Earth's Western Hemisphere, specifically the Americas."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. 3 ...

. This family also includes

railroad worm A railroad worm is a larva or larviform female adult of a beetle of the genus ''Phrixothrix'' in the family Phengodidae, characterized by the possession of two different colors of bioluminescence. It has the appearance of a caterpillar. The ...

s, which are unique among all terrestrial bioluminescent organisms in producing red light. * Family

– Contains around 30 species found in

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

. The validity of this family has not been fully resolved. Rhagophthalmidae was formerly considered to be a subfamily under Phengodidae before being treated as a distinct family. Some authors now believe that it should be classified under Lampyridae.

Fungus gnats

Three genera of fungus gnats are bioluminescent, and known as "glowworms" in their larval stage. They produce a blue-green light. The larvae spin sticky webs to catch food. They are found in caves, overhangs, rock cavities, and other sheltered, wet areas. They are usually classified under the family

Keroplatidae The Keroplatidae are a family of small fly, flies known as fungus gnats. About 950 species are described, but the true number of species is undoubtedly much higher. They are generally forest dwellers found in the damp habitats favoured by their h ...

, but this is not universally accepted and some authors place them under

Mycetophilidae The Mycetophilidae are a family of small flies, forming the bulk of those species known as fungus gnats. About 3000 described species are placed in 150 genera, but the true number of species is undoubtedly much higher. They are generally found ...

instead. Despite the similarities in function and appearance, the bioluminescent systems of the three genera are not homologous and are believed to have evolved separately. * Genus ''

'' – around five species found only in

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

and

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. The best-known member of the genus is the New Zealand glowworm, ''

Arachnocampa luminosa ''Arachnocampa luminosa'' (Skuse, 1891), commonly known as New Zealand glowworm or simply glowworm, is a species of fungus gnat endemic to New Zealand. The larval stage and the imago produce a blue-green bioluminescence. The species is known t ...

.'' The larvae are predatory and use their lights to lure prey into their webs. * Genus '' Orfelia'' – sometimes known as "dismalites". Contains a single species, '' Orfelia fultoni'', found only in

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

. Like ''Arachnocampa'' spp., their larvae may use their lights to attract prey like springtails and other small insects, but their main food is fungal spores. * Genus '' Keroplatus'' – found in

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...

. Unlike ''Arachnocampa'' and ''Orfelia'', the larvae of ''Keroplatus'' feed only on fungal spores. Their bioluminescence is believed to have no function and is

vestigial Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on co ...

References

External links

{{wikiquote, Glowworms
Springbrook Glow Worms Research Centre.
All about glow worms rachnocampa flavain the Gold Coast hinterland, Queensland Australia.
All About Glow Worm in Tamborine, Gold Coast
Descriptive information on Glow Worm Life Cycle and Where are found in Australia.
The UK Glow Worm Survey
has county-by-county lists of glowworm sites in the UK.
An introduction to the fireflies and glow-worms of Europe
information on the biology, life cycle, bioluminescence and evolution of glow-worms. Fly biology Beetles by adaptation Bioluminescent insects Insect common names

Beetles

Fungus gnats

See also

References

External links