Arachnocampa | |
---|---|
Two A. luminosa larvae with their prey snares | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Diptera |
Family: | Keroplatidae |
Genus: | Arachnocampa Edwards, 1924 |
Type species | |
Bolitophila luminosa Skuse, 1891 | |
Species | |
Various - see text | |
Synonyms | |
|
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 grottos, or sheltered places in forests.
A previous placement was in the genus Bolitophila . This species and several related species were moved in 1924 to a new genus, 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.
Arachnocampa species have holometabolous metamorphosis with eggs, larvae, pupae, and adults. Individuals spend most of their lives as larvae. [1]
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. [2]
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..[ citation needed ] Prey include midges, 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, eating other larvae, pupae or adult flies.
The glow is the result of a chemical reaction that involves luciferin, the substrate; luciferase, the enzyme that acts upon luciferin; adenosine triphosphate, the energy molecule; and oxygen. It occurs in modified excretory organs known as Malpighian tubules in the abdomen. [3]
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.
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 of light, mainly during twilight, to attract mates. Light production in the Lampyridae is thought to have originated as a warning signal that the larvae were distasteful. This ability to create light was then co-opted as a mating signal and, in a further development, adult female fireflies of the genus Photuris mimic the flash pattern of the Photinus beetle in order to trap their males as prey.
The Melba Gully State Park was formed to protect a small pocket of natural temperate rainforest in the Otway Ranges near Apollo Bay, Victoria, Australia. The 48-hectare (120-acre) park is extremely valuable as one of the few pockets of natural old-growth Otway Ranges rainforests to survive the logging and subsequent fires, making it a key part of the regeneration of the original Otway Ranges rainforests. The park now forms part of the Great Otway National Park.
Waitomo is a rural community in the King Country region of New Zealand's North Island. There are several solutional cave systems in the area around the village, which are popular tourist attractions. Restaurants and accommodation are centred in the village to serve visiting tourists.
Glowworm or glow-worm is the common name for various groups of insect larvae and adult larviform females that glow through bioluminescence. They include the European common glow-worm and other members of the Lampyridae, but bioluminescence also occurs in the families Elateridae, Phengodidae and Rhagophthalmidae among beetles; as well as members of the genera Arachnocampa, Keroplatus and Orfelia among keroplatid fungus gnats.
The Malpighian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods, arachnids and tardigrades.
Holometabolism, also called complete metamorphosis, is a form of insect development which includes four life stages: egg, larva, pupa, and imago. Holometabolism is a synapomorphic trait of all insects in the superorder Holometabola. Immature stages of holometabolous insects are very different from the mature stage. In some species the holometabolous life cycle prevents larvae from competing with adults because they inhabit different ecological niches. The morphology and behavior of each stage are adapted for different activities. For example, larval traits maximize feeding, growth, and development, while adult traits enable dispersal, mating, and egg laying. Some species of holometabolous insects protect and feed their offspring. Other insect developmental strategies include ametabolism and hemimetabolism.
Fungus gnats are small, dark, short-lived gnats, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae, and Mycetophilidae ; they comprise six of the seven families placed in the superfamily Sciaroidea.
Arachnocampa luminosa, commonly known as New Zealand glowworm or simply glowworm, is a species of fungus gnat, and is solely endemic to New Zealand. The larval stage and the imago produce a blue-green bioluminescence. The species is known to dwell in caves and on sheltered banks in the native bush where humidity is high, as moisture helps to maintain their silk structures that capture prey. Its Māori name is titiwai, meaning "lights reflected in water." This likely derives from the glowworms' presence in natural settings, where their luminous displays are often seen illuminating the cave ceilings.
Glow-Worm Caves Tamborine Mountain is a tourist attraction at Tamborine Mountain in South-East Queensland, Australia.
Mycetophilidae is 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 in the damp habitats favoured by their host fungi and sometimes form dense swarms.
Keroplatidae is a family of small flies known as fungus gnats. About 950 species are described, but the true number of species is undoubtedly much higher. The long-beaked fungus gnats, formerly placed in a separate family Lygistorrhinidae, have been placed into Keroplatidae as subfamily Lygistorrhininae. They are generally forest dwellers found in the damp habitats favoured by their host fungi. They can also often be found in caves. Larvae both feed on fungi and are predatory - they can spin webs by secreting acid fluids, which they use to kill smaller invertebrates and capture spores. Some of the predatory larvae cannibalize pupa of their own species. The family notably includes three genera containing bioluminescent larvae.
The Waitomo Glowworm Caves attraction is a cave at Waitomo on the North Island of New Zealand. It is known for its population of Arachnocampa luminosa, a glowworm species found exclusively in New Zealand. This cave is part of the waitomo streamway system that includes the Ruakuri Cave, Lucky Strike, and Tumutumu Cave.
Lampyris noctiluca, the common glow-worm of Europe, is the type species of beetle in the genus Lampyris and the family Lampyridae.
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.
The Clifden Limestone Cave System is in the Western Southland Region of New Zealand, on private land close to the hamlet of Clifden.
Diptera is an order of winged insects commonly known as flies. Diptera, which are one of the most successful groups of organisms on Earth, are very diverse biologically. None are truly marine but they occupy virtually every terrestrial niche. Many have co-evolved in association with plants and animals. The Diptera are a very significant group in the decomposition and degeneration of plant and animal matter, are instrumental in the breakdown and release of nutrients back into the soil, and whose larvae supplement the diet of higher agrarian organisms. They are also an important component in food chains.
Ruakuri Cave is one of the longer caves in the Waitomo area of New Zealand. It was first discovered by local Māori between 400 and 500 years ago. The name Te Ruakuri, or "The Den of Dogs" was given to the surrounding area when wild dogs were discovered living in the entrance of the cave.
Phengodes laticollis is a species of the beetle within the family of Phengodidae. The name Phengodidae is the scientific name for a beetle in which their larvae are glowworms and are thus named for their bioluminescent qualities. The beetle family is primarily found in the New World, where most of the diversity in this particular species of beetle is found in tropical America. They are also a species in which are deemed vulnerable, particularly in West Virginia. Within the Phengodes lacticollis, the females are larger than the males and the females are in larviform. The males are luminescent, the females and the larvae, however, have luminescent organs on their trunk segments. This allows for yellow or green light production.
The Waitomo Caves Discovery Centre is a museum located in the town of Waitomo in the North Island of New Zealand. The museum is also referred to as the Waitomo Caves Discovery Centre, the Waitomo Museum of Caves and the Waitomo Education Centre.
Forsteropsalis photophaga, also known as the glow-worm hunter, is a species of long-legged harvestman in the family Neopilionidae. This species is endemic to New Zealand, found in North Island caves in the vicinity of Waitomo. The name "photophaga" comes from their habit of feeding on the luminescent larvae, pupae, and adults of the New Zealand glow-worm Arachnocampa luminosa.