Glowworm
Encyclopedia
Glowworm, or glow worm, is the common name for various groups of insect larva
e and adult larviform female
s that glow through bioluminescence
. They may sometimes resemble worm
s, but all are insects (Arachnocampa
and Orfelia being flies
and all the others being beetle
s).
Groups include:
s in the Phengodidae family have an additional red light at their head. The fly larvae produce a blue-green colour. The glow is produced by different organs in the different families, suggesting they evolved
separately, though several other beetle families in the superfamily Cantharoidea also exhibit bioluminescence, suggesting a single origin within this lineage and hence that the Lampyrids and Phengodids share a bioluminescent ancestor. The chemical reaction in each case is very efficient
; nearly 100% of the energy input is turned into light (compared to the best light-emitting diode
s at just 22%).
The purpose of the glow varies. Those adult females that glow do so to attract a male for mating. The Lampyridae larvae are believed to glow as a warning signal (see aposematism
) to predators like toad
s not to eat them as they are mildly toxic. But the Arachnocampa
and Orfelia larvae, on the other hand, glow to attract prey like midge
s into sticky snare lines for the larva to feed on.
Larva
A larva 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...
e and adult larviform female
Larviform female
Larviform female is biological phenomenon occurring in some species, where the females in the adult stage of metamorphosis resemble the larvae to various degrees. Typically, the female is wingless and generally larger than the male...
s that glow through bioluminescence
Bioluminescence
Bioluminescence is the production and emission of light by a living organism. Its name is a hybrid word, originating from the Greek bios for "living" and the Latin lumen "light". Bioluminescence is a naturally occurring form of chemiluminescence where energy is released by a chemical reaction in...
. They may sometimes resemble worm
Worm
The term worm refers to an obsolete taxon used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, and stems from the Old English word wyrm. Currently it is used to describe many different distantly-related animals that typically have a long cylindrical...
s, but all are insects (Arachnocampa
Arachnocampa
Arachnocampa is a genus of four fungus gnat species which are, in their larval stage, glowworms. They are found mostly in New Zealand and Australia in caves and grottos, or sheltered places in forests....
and Orfelia being flies
Fly
True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...
and all the others being beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
s).
Classification
Major families are:- Lampyridae (fireflies), found around the world. The wingless adult female is the glowworm of literature, especially Lampyris noctilucaLampyris noctilucaLampyris noctiluca, the common glow-worm of Europe , is a firefly species of the genus Lampyris. These are beetles, as evidenced by the hard cases which close over the wings when they are not in use....
(the "Glow-worm" proper of British EnglishBritish EnglishBritish English, or English , is the broad term used to distinguish the forms of the English language used in the United Kingdom from forms used elsewhere...
) found in most of EuropeEuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. In this species the male flies but does not glow. In some areas, a FireflyFireflyLampyridae is a family of insects in the beetle order Coleoptera. They are winged beetles, and commonly called fireflies or lightning bugs for their conspicuous crepuscular use of bioluminescence to attract mates or prey. Fireflies produce a "cold light", with no infrared or ultraviolet frequencies...
can also refer to members of the LuciolaLuciolaLuciola is a genus of "flashing" fireflies , especially well-known from Japan. They are often called "Japanese fireflies", but their members range farther into Asia and reach southern Europe and Africa...
genus in the same family, found commonly throughout EuropeEuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, in which both the males and the flightless females glow. - PhengodidaePhengodidaeThe 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...
, found in North AmericaNorth AmericaNorth America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and South AmericaSouth AmericaSouth America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east... - RhagophthalmidaeRhagophthalmidaeRhagophthalmidae is a family of beetles within the larger Elateroidea group that include click-beetles. Members of this beetle family have bioluminescent organs on the larvae and are closely related to the Phengodidae and Lampyridae , and were often included in one of these families as a...
, found in AsiaAsiaAsia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population... - Keroplatidae (flies, order DipteraDipteraDiptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...
): the genus ArachnocampaArachnocampaArachnocampa is a genus of four fungus gnat species which are, in their larval stage, glowworms. They are found mostly in New Zealand and Australia in caves and grottos, or sheltered places in forests....
(formerly called Bolitiphila), found in New ZealandNew ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
and AustraliaAustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area... - MycetophilidaeMycetophilidaeMycetophilidae is a family of small flies, forming the bulk of those species known as fungus gnats. There are approximately 3000 described species in 150 genera but the true number of species is undoubtedly much higher...
(flies, order DipteraDipteraDiptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...
): Orfelia fultoniOrfelia fultoniOrfelia fultoni is the only bioluminescent member of Diptera found in North America. It is distantly related to Arachnocampa. The larvae of the species live in stream banks among moss and rock cavities, as well as in wet sandstone caves. They build sticky webs, and using their two bioluminescent...
("dismalites"), a single species of fungus gnatFungus gnatFungus gnats are small, dark, short-lived flies, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae and Mycetophilidae , sometimes placed in the superfamily Mycetophiloidea, whose larvae feed on plant roots or fungi and aid in the decomposition of organic matter...
, distantly related to ArachnocampaArachnocampaArachnocampa is a genus of four fungus gnat species which are, in their larval stage, glowworms. They are found mostly in New Zealand and Australia in caves and grottos, or sheltered places in forests....
, found in North AmericaNorth AmericaNorth America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
.
Groups include:
- Lampyridae
- PhengodidaePhengodidaeThe 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...
- Railroad wormRailroad wormA railroad worm is a larva or larviform female adult of a beetle of the genus Phrixothrix in the family Phengodidae, characterized by their unique possession of two different colors of bioluminescence...
- ArachnocampaArachnocampaArachnocampa is a genus of four fungus gnat species which are, in their larval stage, glowworms. They are found mostly in New Zealand and Australia in caves and grottos, or sheltered places in forests....
- Orfelia fultoniOrfelia fultoniOrfelia fultoni is the only bioluminescent member of Diptera found in North America. It is distantly related to Arachnocampa. The larvae of the species live in stream banks among moss and rock cavities, as well as in wet sandstone caves. They build sticky webs, and using their two bioluminescent...
Glow
The glow in the former two groups is a yellow-green colour. The so-called railroad wormRailroad worm
A railroad worm is a larva or larviform female adult of a beetle of the genus Phrixothrix in the family Phengodidae, characterized by their unique possession of two different colors of bioluminescence...
s in the Phengodidae family have an additional red light at their head. The fly larvae produce a blue-green colour. The glow is produced by different organs in the different families, suggesting they evolved
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
separately, though several other beetle families in the superfamily Cantharoidea also exhibit bioluminescence, suggesting a single origin within this lineage and hence that the Lampyrids and Phengodids share a bioluminescent ancestor. The chemical reaction in each case is very efficient
Luminous efficacy
Luminous efficacy is a measure of how well a light source produces visible light. It is the ratio of luminous flux to power. Depending on context, the power can be either the radiant flux of the source's output, or it can be the total electric power consumed by the source.Which sense of the term is...
; nearly 100% of the energy input is turned into light (compared to the best light-emitting diode
Light-emitting diode
A light-emitting diode is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting...
s at just 22%).
The purpose of the glow varies. Those adult females that glow do so to attract a male for mating. The Lampyridae larvae are believed to glow as a warning signal (see aposematism
Aposematism
Aposematism , perhaps most commonly known in the context of warning colouration, describes a family of antipredator adaptations where a warning signal is associated with the unprofitability of a prey item to potential predators...
) to predators like toad
Toad
A toad is any of a number of species of amphibians in the order Anura characterized by dry, leathery skin , short legs, and snoat-like parotoid glands...
s not to eat them as they are mildly toxic. But the Arachnocampa
Arachnocampa
Arachnocampa is a genus of four fungus gnat species which are, in their larval stage, glowworms. They are found mostly in New Zealand and Australia in caves and grottos, or sheltered places in forests....
and Orfelia larvae, on the other hand, glow to attract prey like midge
Midge (insect)
Midges comprise many kinds of very small two-winged flies found world-wide. The term does not encapsulate a well-defined taxonomic group, but includes animals in several families of Nematoceran Diptera. While some midges are vectors for disease, many others play useful roles as prey items for...
s into sticky snare lines for the larva to feed on.
Habitat locations
- New ZealandNew ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
- Waitomo CavesWaitomo CavesThe Waitomo Caves are a village and cave system forming a major tourist attraction in the southern Waikato region of the North Island of New Zealand, 12 kilometres northwest of Te Kuiti. The community of Waitomo Caves itself is very small, though the village has many temporary service workers...
, Waitomo, Waikato - Te Ana-au CavesTe Ana-au CavesThe Te Ana-au caves are a culturally and ecologically important system of limestone caves on the western shore of Lake Te Anau, in the southwest of New Zealand. It was discovered in 1948 by Lawson Burrows, who found the upper entry after three years of searching, following clues in old Māori legends...
, Lake Te Anau, Fiordland, South Island - Wellington Botanic GardenWellington Botanic GardenThe Wellington Botanic Garden, Wellington, New Zealand, covers 25 hectares of land on the side of the hill between Thorndon and Kelburn, near central Wellington....
- Hari Hari, Westland
- Waimarino Adventure ParkWaimarino Adventure ParkWaimarino Adventure Park is a kayak and adventure destination located in Tauranga, New Zealand. It is set among native bushland on the banks of the Wairoa River...
, Tauranga
- Waitomo Caves
- AustraliaAustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
- Glow-Worm Caves Tamborine Mountain, Southeastern QueenslandQueenslandQueensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
- Newnes glow worm tunnelNewnes Glow Worm TunnelThe Newnes glow worm tunnel is a disused railway tunnel in the Wolgan Valley, New South Wales, Australia, that is famous for its resident glow worms, the bioluminescent larvae of Arachnocampa richardsae, a type of fungus gnat.-Description and history:...
, Blue Mountains, New South WalesNew South WalesNew South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales... - Natural Bridge, Gold Coast hinterland, QueenslandQueenslandQueensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
- Glow-Worm Caves Tamborine Mountain, Southeastern Queensland
- Dismals CanyonDismals CanyonDismals Canyon is a sandstone gorge near Phil Campbell in Franklin County, Alabama. It was declared a National Natural Landmark in May 1974.Dismals Canyon is one of only a few places where insects called dismalites can be found. The larval forms of these flies emit a bright blue-green light to...
, AlabamaAlabamaAlabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
, United StatesUnited StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
External links
- 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