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.
Th ...
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 ...
. They include the European
common glow-worm and other members of the
Lampyridae
The Lampyridae are a family of elateroid beetles with more than 2,000 described species, many of which are light-emitting. They are soft-bodied beetles commonly called fireflies, lightning bugs, or glowworms for their conspicuous production ...
, 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 bioluminescent organs. They occur throughout the New World from extreme southern Canada to Chile. The recently r ...
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 h ...
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
''Keroplatus'' is a genus of predatory fungus gnats in the family Keroplatidae. Several species are bioluminescent.V.R. Viviani, D.T. Amaral, V.R. Bevilaqua, R.L. Falaschi (2018) ''Orfelia''-type luciferin and its associated storage protein in th ...
and
Orfelia
''Orfelia'' is a cosmopolitan genus of flies in the family Keroplatidae.
Species
*''Orfelia affinis'' ( Brunetti, 1912)
*''Orfelia amurensis'' Zaitzev, 1994
*''Orfelia angulata'' (Sasakawa, 1994)
*''Orfelia angustata'' (Van Duzee, 1928)
*''Orf ...
among
keroplatid fungus gnat
Fungus gnats are small, dark, short-lived gnats, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae, and Mycetophilidae (order Diptera); they comprise six of the seven families placed in the superfamily Sciar ...
s.
Beetles
Four families of beetles are
bioluminescent
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 ...
. The wingless
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 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 ...
. 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
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 ...
– 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, ...
n islands are bioluminescent. All of them are members of the subfamily Pyrophorinae, except for one species, ''
Campyloxenus pyrothorax'', which belongs to subfamily Campyloxeninae, and ''
Balgus schnusei'', in
Thylacosterninae.
* Family
Lampyridae
The Lampyridae are a family of elateroid beetles with more than 2,000 described species, many of which are light-emitting. They are soft-bodied beetles commonly called fireflies, lightning bugs, or glowworms for their conspicuous production ...
– True Fireflies. Contains around 2,000 species found throughout the world. Some "Glow worms" are in this family.
* Family
Phengodidae
The beetle family Phengodidae is known also as glowworm beetles, whose larvae are known as glowworms. The females and larvae have bioluminescent organs. They occur throughout the New World from extreme southern Canada to Chile. The recently r ...
– 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 els ...
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. ...
. 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
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 h ...
– 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 ...
. 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 gnat
Fungus gnats are small, dark, short-lived gnats, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae, and Mycetophilidae (order Diptera); they comprise six of the seven families placed in the superfamily Sciar ...
s 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 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 host ...
, 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
Homology may refer to:
Sciences
Biology
*Homology (biology), any characteristic of biological organisms that is derived from a common ancestor
*Sequence homology, biological homology between DNA, RNA, or protein sequences
* Homologous chrom ...
and are believed to have evolved separately.
* Genus ''
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 ...
'' – 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 List of islands of New Zealand, smaller islands. It is the ...
and
Australia. 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 to d ...
.'' The larvae are predatory and use their lights to lure prey into their webs.
* Genus ''
Orfelia
''Orfelia'' is a cosmopolitan genus of flies in the family Keroplatidae.
Species
*''Orfelia affinis'' ( Brunetti, 1912)
*''Orfelia amurensis'' Zaitzev, 1994
*''Orfelia angulata'' (Sasakawa, 1994)
*''Orfelia angustata'' (Van Duzee, 1928)
*''Orf ...
'' – sometimes known as "dismalites". Contains a single species, ''
Orfelia fultoni
''Orfelia fultoni'' or “dismalites” is a carnivorous species of fly larvae. It is the only bioluminescent species of dipteran fly found in North America. They produce the bluest light of any studied bioluminescent insect.
Discovery
''O. ful ...
'', found only in
North America. 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
''Keroplatus'' is a genus of predatory fungus gnats in the family Keroplatidae. Several species are bioluminescent.V.R. Viviani, D.T. Amaral, V.R. Bevilaqua, R.L. Falaschi (2018) ''Orfelia''-type luciferin and its associated storage protein in th ...
'' – 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 archipelag ...
. 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 ...
.
See also
*
Larviform
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 Surveyhas county-by-county lists of glowworm sites in the UK.
An introduction to the fireflies and glow-worms of Europeinformation on the biology, life cycle, bioluminescence and evolution of glow-worms.
Fly biology
Beetles by adaptation
Bioluminescent insects
Insect common names