''Arachnocampa'' is a genus of nine

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 Sciaroide ...

species which have a

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 Fungus, fungi, microorganisms including ...

larval 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 l ...

stage, akin to the larval stage of glowworm beetles. The species of ''Arachnocampa'' are endemic to

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 ...

and New Zealand, dwelling in caves and grottos, or sheltered places in forests. A previous

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

was "''Bolitiphila''," meaning " mushroom lover," in the past. The name was changed in 1924 to ''Arachnocampa'', meaning " spider web-worm," for the way the larvae hang sticky silk threads to ensnare prey. The genus ''Arachnocampa'' belongs in the family Keroplatidae.

Common features

''Arachnocampa'' species have holometabolous metamorphosis with eggs, larvae, pupae, and adults. Individuals spend most of their lives as larvae. These flies live from about 6 through 12 months as larvae, depending on food availability. A larva is only about 3–5 mm long when it emerges from its egg, and can grow up to about 3 cm long. The larva spins a nest out of silk on the ceiling of the cave and then hangs down as many as 70 threads of silk (called snares) from around the nest, each up to 30 or 40 cm long and holding droplets of mucus. The larvae can only live in a place out of the wind, to stop their lines being tangled, hence caves, overhangs or deep rainforest. In some species, the droplets of mucus on the silk threads are poisonous, enhancing the trap's ability to subdue prey quickly. A larva's glow attracts prey into its threads. The roof of a cave covered with larva can look remarkably like a blue starry sky at night. A hungry larva glows brighter than one that has just eaten.. Prey include

midge A midge is any small fly, including species in several families of non-mosquito Nematoceran Diptera. Midges are found (seasonally or otherwise) on practically every land area outside permanently arid deserts and the frigid zones. Some mid ...

s, mayflies, caddisflies, mosquitos, moths, and even small snails or millipedes. When a prey animal is caught by a snare, its larva pulls it up (at up to about 2 mm a second) and feeds on the prey. When ''Arachnocampa'' prey are scarce, larvae may show

cannibalism Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is well documented, b ...

, eating other larvae, pupae or adult flies. The glow is the result of a chemical reaction that involves luciferin, the substrate;

luciferase Luciferase is a generic term for the class of oxidative enzymes that produce bioluminescence, and is usually distinguished from a photoprotein. The name was first used by Raphaël Dubois who invented the words ''luciferin'' and ''luciferase'', ...

, the enzyme that acts upon luciferin; adenosine triphosphate, the energy molecule; and oxygen. It occurs in modified excretory organs known as

Malpighian tubules The Malpighian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods, arachnids and tardigrades. The system consists of branching tubules extending from the alimentary canal that absorbs solutes, water, ...

in the abdomen. The body of the larva is soft while the head capsule is hard. When it outgrows the head capsule it moults, shedding its skin. This happens four times throughout its life. At the end of the larva stage, it becomes a pupa, hanging down from the roof of the cave. The pupa stage lasts about 1 or 2 weeks and it glows intermittently. The male stops glowing a few days before emerging, the female's glow increases. The glow from the female is believed to be to attract a mate, and males may be waiting there when she emerges. The adults of both sexes cannot feed and live only a short time. They glow, but only intermittently. Their sole purpose is to mate, and for the female to lay eggs. Adult insects are poor fliers and so will often remain in the same area, building a colony of glowworms. The female lays a total of about 130 eggs, in clumps of 40 or 50, and dies soon after laying. The eggs hatch after about 20 days and the cycle repeats. The larvae are sensitive to light and disturbance and will retreat into their nests and stop glowing if they or their snares are touched. Generally they have few predators. Their greatest danger is from human interference.

Species

*'' Arachnocampa buffaloensis'' Baker, 2010 is found in an alpine cave on

Mount Buffalo Mount Buffalo is a mountain plateau of the Australian Alps and is within the Mount Buffalo National Park in Victoria, Australia. It is located approximately northeast of Melbourne. It is noted for its dramatic scenery. The summit of the highes ...

in Victoria. Its presence suggests

rainforest Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores ...

may have extended up the mountain in the past.''The Lure of Glow Worms''
science feature at the Australian Broadcasting Corporation This species is listed as a threatened species in Victoria (listed as ''Arachnocampa'' sp. "Mount Buffalo glow-worm"). *''

Arachnocampa flava ''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 grott ...

'' Harrison, 1966 is found in Queensland. The

Natural Bridge A natural arch, natural bridge, or (less commonly) rock arch is a natural landform where an arch has formed with an opening underneath. Natural arches commonly form where inland cliffs, coastal cliffs, fins or stacks are subject to erosion fr ...

in the Gold Coast hinterland is one well-known habitat. *''

Arachnocampa gippslandensis ''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 grott ...

'' Baker, 2010 - eastern Victoria *'' Arachnocampa girraweenensis'' Baker, 2010 - southeast Queensland and northern New South Wales *''

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 ...

'' ( Skuse, 1891) is found in New Zealand, in both the North and

South South is one of the cardinal directions or Points of the compass, compass points. The direction is the opposite of north and is perpendicular to both east and west. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Pro ...

islands. *''

Arachnocampa otwayensis ''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 grott ...

'' Baker, 2010 - western Victoria *'' Arachnocampa richardsae'' Harrison, 1966 is found in New South Wales. The Newnes glow worm tunnel in the Blue Mountains is one well-known habitat. *''

Arachnocampa tasmaniensis ''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 ...

'' Ferguson, 1925 is found in Tasmania (as the name suggests). One habitat is the Marakoopa Cave, Mole Creek near

Cradle Mountain Cradle Mountain is a locality and mountain in the Central Highlands region of the Australian state of Tasmania. The mountain is situated in the Cradle Mountain-Lake St Clair National Park. At above sea level, it is the sixth-highest mountai ...

. *'' Arachnocampa tropica'' Baker, 2010 - north Queensland

References

External links

Atlas of Living Australia: ''Arachnocampa''

Soil Bugs - An illustrated guide to the New Zealand invertebrates

Glowworm article in the ''Encyclopaedia of New Zealand 1966''

2009-10-25) {{Taxonbar, from=Q310057 Keroplatidae Sciaroidea genera Diptera of New Zealand Insects of Australia Bioluminescent insects Cave insects

Common features

Species

See also

References

Further reading

External links