53-467: The Mesostoinae is a subfamily of braconid wasps with a Gondwanan distribution . The members of this family display sexual dimorphism , males are brachypterous , which means that they have reduced, non-functional wings. The Mesostoini and Hydrangeocolini include primary gall formers on Banksia and parasites of the gall-forming Cecidomyiidae . The Avgini include parasitoids of leaf-mining and leaf-rolling Lepidoptera . This subfamily contains
106-472: A dose of 400 to 1000 rads can kill an average human, a dose of 180,000 rads was required to kill a braconid of genus Habrobracon in an experiment. Parasitoid#Types of parasitoids In evolutionary ecology , a parasitoid is an organism that lives in close association with its host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionary strategies within parasitism , distinguished by
159-539: A few species are parasitic. The larvae of Epipyropidae feed on Homoptera such as leafhoppers and cicadas, and sometimes on other Lepidoptera. The larvae of Cyclotornidae parasitise first Homoptera and later ant brood. The pyralid moth Chalcoela has been used in biological control of the wasp Polistes in the Galapagos Islands . Parasitism is rare in the Trichoptera (caddisflies), but it
212-401: A host that continues to grow larger and avoid predators. Primary parasitoids have the simplest parasitic relationship, involving two organisms, the host and the parasitoid. Hyperparasitoids are parasitoids of parasitoids; secondary parasitoids have a primary parasitoid as their host, so there are three organisms involved. Hyperparasitoids are either facultative (can be a primary parasitoid or
265-469: A hyperparasitoid depending on the situation) or obligate (always develop as a hyperparasitoid). Levels of parasitoids beyond secondary also occur, especially among facultative parasitoids. In oak gall systems, there can be up to five levels of parasitism. Cases in which two or more species of parasitoids simultaneously attack the same host without parasitizing each other are called multi- or multiple parasitism. In many cases, multiple parasitism still leads to
318-520: A large stalk, growing from the back of the ant's head which subsequently releases ascospores. These spores are too large to be wind dispersed and instead fall directly to the ground where they produce secondary spores that infect ants as they walk over them. O. sinesis , is a parasitoid as well, parasitising ghost moth larvae, killing them within 15-25 days, a similar process to that of O. unilateralis . Host location has been studied in Ormia ochracea ,
371-808: A lepidopteran moth known for being a pest of maize in East Asia), the African sugarcane borer (a moth commonly found in sub-Saharan Africa), the butterfly Danaus chrysippus in Ghana , and Liriomyza trifolii (the American serpentine leafminer) and Manduca quinquemaculata (the tomato hornworm) in North America. Braconids often will prey on fruit fly larvae like Anastrepha suspensa as well. Endoparasitoid species often display elaborate physiological adaptations to enhance larval survival within
424-409: A living host which they eventually kill, typically before it can produce offspring, whereas conventional parasites usually do not kill their hosts, and predators typically kill their prey immediately. Parasitoids can be classified as either endo- or ectoparasitoids with idiobiont or koinobiont developmental strategies. Endoparasitoids live within their host's body, while ectoparasitoids feed on
477-534: A parasitoid tachinid fly that locates their field cricket host acoustically ( phonotaxis ). Preference for the dominant local host species was not explained by DNA analysis. In fact, populations across the southern U.S. were inexplicably closely related, considering rate of range expansion from a presumed Central American origin. A captive population of lab-reared flies were raised on two different host songs ( Gryllus integer or G. lineaticeps ). Responsive adult females overwhelmingly chose their familiar song, indicating
530-399: A range of obstacles to oviposition, including behavioural, morphological, physiological and immunological defences of their hosts. To thwart this, some wasps inundate their host with their eggs so as to overload its immune system's ability to encapsulate foreign bodies; others introduce a virus which interferes with the host's immune system. Some parasitoid wasps locate hosts by detecting
583-454: A wide range of insects including caterpillars, adult and larval beetles , and true bugs . Commercially, there are two types of rearing systems: short-term seasonal daily output with high production of parasitoids per day, and long-term year-round low daily output with a range in production of 4–1000 million female parasitoids per week, to meet demand for suitable biological control agents for different crops. Maria Sibylla Merian (1647–1717)
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#1732791439891636-696: Is found among the Hydroptilidae (purse-case caddisflies), probably including all 10 species in the Orthotrichia aberrans group; they parasitise the pupae of other trichopterans. Mites of the family Acarophenacidae are ectoparasitoids of insect eggs. Unlike the insect parasitoids, it is the adult stage in Acarophenacidae that acts as a parasitoid. Specifically, adult female mites feed on insect eggs and their body swells up with offspring, which eventually emerge as adults. All known fungi in
689-492: Is notable. They are often black-brown (sometimes with reddish markings), though some species exhibit striking coloration and patterns, being parts of Müllerian mimicry complexes . They have one or no recurrent veins, unlike other members of the other family in Ichneumonoidea ( Ichneumonidae ), which usually have two. Wing venation patterns are otherwise highly variable. The antennae typically have 16 segments or more;
742-737: Is parasitoidal on cicadas, locating its host by sound. The Strepsiptera (twisted-wing parasites) consist entirely of parasitoids; they usually sterilise their hosts. Two beetle families, Ripiphoridae (450 species ) and Rhipiceridae , are largely parasitoids, as are Aleochara Staphylinidae ; in all, some 400 staphylinids are parasitoidal. Some 1,600 species of the large and mainly freeliving family Carabidae are parasitoids. A few Neuroptera are parasitoidal; they have larvae that actively search for hosts. The larvae of some Mantispidae , subfamily Symphrasinae, are parasitoids of other arthropods including bees and wasps. Although nearly all Lepidoptera (butterflies and moths) are herbivorous,
795-411: Is similarly far higher than for screening chemicals: 1:30 against 1:5 respectively, since the search for suitable natural enemies can be guided accurately with ecological knowledge. Natural enemies are more difficult to produce and to distribute than chemicals, as they have a shelf life of weeks at most; and they face a commercial obstacle, namely that they cannot be patented. From the point of view of
848-540: The Diptera , Coleoptera and other orders of endopterygote insects . Some of these, usually but not only wasps, are used in biological pest control . The 17th-century zoological artist Maria Sibylla Merian closely observed parasitoids and their hosts in her paintings. The biology of parasitoidism influenced Charles Darwin 's beliefs and has inspired science fiction authors and scriptwriters to create numerous parasitoidal aliens that kill their human hosts, such as
901-604: The alien species in Ridley Scott 's 1979 film Alien . The term "parasitoid" was coined in 1913 by the Swedo-Finnish writer Odo Reuter , and adopted in English by his reviewer, the entomologist William Morton Wheeler . Reuter used it to describe the strategy where the parasite develops in or on the body of a single host individual, eventually killing that host, while the adult is free-living. Since that time,
954-845: The larval stages of Coleoptera , Diptera , and Lepidoptera , but also some hemimetabolous insects such as aphids , Heteroptera , or Embiidina . Most species kill their hosts, though some cause the hosts to become sterile and less active. Parasitoidy on adult insects (particularly on Hemiptera and Coleoptera) also occurs. Members of two subfamilies, the Mesostoinae and Doryctinae are known to form galls on plants. Braconids are often used as biological pest control agents, especially against aphids. Thousands of species of insects are used as hosts by braconid wasps. A few notable examples are detailed here. Some species of braconids are parasitoids of Ostrinia furnacalis (the Asian corn borer,
1007-1035: The phylogenetic tree ; groups containing parasitoids are shown in boldface, e.g. Coleoptera , with the number of times parasitoidism evolved in the group in parentheses, e.g. (10 clades) . The approximate number (estimates can vary widely) of parasitoid species out of the total is shown in square brackets, e.g. [2,500 of 400,000]. Raphidioptera Megaloptera Neuroptera (net-winged insects) (1 clade) [c. 15 of 6,000] Coleoptera (beetles) (10 clades) [c. 2,500 of 400,000] [REDACTED] Strepsiptera (twisted-wing parasites) [600 of 600] [REDACTED] Symphyta Orussoidea (parasitic wood wasps) [75 of 75] [REDACTED] Apocrita (wasp-waisted insects) [c. 50,000 of 100,000] [REDACTED] Diptera (true flies) (21 clades) [c. 17,000 of 125,000] [REDACTED] Mecoptera Siphonaptera Trichoptera (caddis flies) (1 clade) [c. 10 of 14,500] Lepidoptera (butterflies, moths) (2 clades) [c. 40 of 180,000] [REDACTED] Within
1060-648: The trochanters have two segments. Females often have long ovipositors , an organ that largely varies interspecifically. This variation is closely related to the host species upon which the wasp deposits its egg. Species that parasitize microlepidopterans , for instance, have longer ovipositors, presumably to reach the caterpillar through layers of plant tissue. Some wasps also have long ovipositors to bypass caterpillar defense mechanisms such as spines or hairs, or to reach deeply-burrowed Coleoptera larvae in tree trunks. The larvae of most braconids are internal or external primary parasitoids of other insects , especially
1113-412: The 'death bite'. This approach is so fine-tuned it causes the ant to bite down on the part of the leaf most optimal for the fungus to fruit; the adaxial leaf midrib. In fact, it has been found that in specific circumstances, the time of the death bite is synchronised to solar noon. As much as 40% of the ant's biomass is fungal hyphae at the moment of the death bite. After the ant dies, the fungus produces
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#17327914398911166-760: The Hymenoptera, parasitoidism evolved just once, and the many described species of parasitoid wasps represent the great majority of species in the order, barring those like the ants , bees , and Vespidae wasps that have secondarily lost the parasitoid habit. The parasitoid wasps include some 25,000 Ichneumonoidea , 22,000 Chalcidoidea , 5,500 Vespoidea , 4,000 Platygastroidea , 3,000 Chrysidoidea , 2,300 Cynipoidea , and many smaller families. These often have remarkable life cycles. They can be classified as either endoparasitic or ectoparasitic according to where they lay their eggs. Endoparasitic wasps insert their eggs inside their host, usually as koinobionts, allowing
1219-601: The Lepidoptera, 10 times or more in Coleoptera, and no less than 21 times among the Diptera. These are all holometabolous insects ( Endopterygota , which form a single clade ), and it is always the larvae that are parasitoidal. The metamorphosis from active larva to an adult with a different body structure permits the dual lifestyle of parasitic larva, freeliving adult in this group. These relationships are shown on
1272-530: The best-known is the Xenomorph in Ridley Scott 's 1979 film Alien , which runs rapidly through its lifecycle from violently entering a human host's mouth to bursting fatally from the host's chest. The molecular biologist Alex Sercel, writing in Signal to Noise Magazine , compares "the biology of the [ Alien ] Xenomorphs to parasitoid wasps and nematomorph worms from Earth to illustrate how close to reality
1325-519: The biology of these aliens is and to discuss this exceptional instance of science inspiring artists". Sercel notes that the way the Xenomorph grasps a human's face to implant its embryo is comparable to the way a parasitoid wasp lays its eggs in a living host. He further compares the Xenomorph life cycle to that of the nematomorph Paragordius tricuspidatus which grows to fill its host's body cavity before bursting out and killing it. Alistair Dove, on
1378-776: The chemicals that plants release to defend against insect herbivores. The true flies ( Diptera ) include several families of parasitoids, the largest of which is the Tachinidae (some 9,200 species ), followed by the Bombyliidae (some 4,500 species ), along with the Pipunculidae and the Conopidae , which includes parasitoidal genera such as Stylogaster . Other families of flies include some protelean species. Some Phoridae are parasitoids of ants. Some flesh flies are parasitoids: for instance Emblemasoma auditrix
1431-440: The concept has been generalised and widely applied. A perspective on the evolutionary options can be gained by considering four questions: the effect on the reproductive fitness of a parasite's hosts; the number of hosts they have per life stage; whether the host is prevented from reproducing; and whether the effect depends on intensity (number of parasites per host). From this analysis, proposed by K. D. Lafferty and A. M. Kunis,
1484-465: The cyclostomes and noncyclostomes. In cyclostome braconids, the labrum and the lower part of the clypeus are concave with respect to the upper clypeus and the dorsal margin of the mandibles. These groups may be clades that diverged early in the evolution of braconids. Cyclostomes are monophyletic whereas noncyclostomes can be divided formally into microgastroids, sigalphoids, helconoids, and euphoroids. The morphological variation among braconids
1537-403: The death of one or more of the parasitoids involved. If multiple parasitoids of the same species coexist in a single host, it is called superparasitism . Gregarious species lay multiple eggs or polyembryonic eggs which lead to multiple larvae in a single host. The end result of gregarious superparasitism can be a single surviving parasitoid individual or multiple surviving individuals, depending on
1590-456: The eggs or larvae of their host, but some attack adults. Oviposition depends on finding the host and on evading host defences; the ovipositor is a tube-like organ used to inject eggs into hosts, sometimes much longer than the wasp's body. Hosts such as ants often behave as if aware of the wasps' presence, making violent movements to prevent oviposition. Wasps may wait for the host to stop moving, and then attack suddenly. Parasitoid wasps face
1643-530: The extraordinarily fast range expansion of O. ochracea, as well as the presence and power of learning in parasitoids. Parasitoids are among the most widely used biological control agents. Classic biological pest control using natural enemies of pests (parasitoids or predators) is extremely cost effective, the cost/benefit ratio for classic control being 1:250, but the technique is more variable in its effects than pesticides; it reduces rather than eliminates pests. The cost/benefit ratio for screening natural enemies
Mesostoinae - Misplaced Pages Continue
1696-414: The farmer or horticulturalist, the most important groups are the ichneumonid wasps , which prey mainly on caterpillars of butterflies and moths ; braconid wasps , which attack caterpillars and a wide range of other insects including greenfly ; chalcidoid wasps , which parasitise eggs and larvae of greenfly, whitefly , cabbage caterpillars , and scale insects ; and tachinid flies , which parasitise
1749-511: The fatal prognosis for the host, which makes the strategy close to predation . Among parasitoids, strategies range from living inside the host ( endoparasitism ), allowing it to continue growing before emerging as an adult, to paralysing the host and living outside it ( ectoparasitism ). Hosts can include other parasitoids, resulting in hyperparasitism ; in the case of oak galls , up to five levels of parasitism are possible. Some parasitoids influence their host's behaviour in ways that favour
1802-407: The following thirteen genera: [REDACTED] Data related to Mesostoinae at Wikispecies This Ichneumonoidea -related article is a stub . You can help Misplaced Pages by expanding it . Braconidae 47, see text Stenophasmidae Benoit, 1949 The Braconidae are a family of parasitoid wasps . After the closely related Ichneumonidae , braconids make up the second-largest family in
1855-428: The genera Cordyceps and Ophiocordyceps are endoparasitic. One of the most notable fungal parasitoids is O. unilateralis which infects carpenter ants by breaching the ant's exoskeletons via their spores and growing in the ant's hemocoel as free living yeast cells. Eventually the yeast cells progress to producing nerve toxins to alter the behaviour of the ant causing it to climb and bite onto vegetation, known as
1908-627: The hind wing is in 95% of Braconidae basal to the separation of R1 and Rs (it is opposite or apical in Ichneumonidae). In Braconidae, metasomal tergum 2 is fused with tergum 3, (secondarily flexible in Aphidiinae) – 90% of Ichneumonidae have a flexible suture. The species Microplitis croceipes possesses an extremely accurate sense of smell and can be trained for use in narcotics and explosives detection . At least some braconids appear to be very resistant to ionizing radiation . While
1961-399: The hive. About 10% of described insects are parasitoids, in the orders Hymenoptera , Diptera , Coleoptera , Neuroptera , Lepidoptera , Strepsiptera , and Trichoptera . The majority are wasps within the Hymenoptera; most of the others are Dipteran flies. Parasitoidism has evolved independently many times: once each in Hymenoptera, Strepsiptera, Neuroptera, and Trichoptera, twice in
2014-537: The host caterpillar. Through the evolutionary history of being used by the wasps, these viruses apparently have become so modified, they appear unlike any other known viruses today. Because of this highly modified system of host immunosuppression , a high level of parasitoid-host specificity is not surprising. The family seems to date from early Cretaceous (provided that Eobracon is properly assigned to this family). It underwent extensive diversification from mid or late Cretaceous to early Cenozoic , correlating with
2067-410: The host from outside. Idiobiont parasitoids prevent further development of the host after initially immobilising it, whereas koinobiont parasitoids allow the host to continue its development while feeding upon it. Most ectoparasitoids are idiobiont, as the host could damage or dislodge the external parasitoid if allowed to move and moult . Most endoparasitoids are koinobionts, giving them the advantage of
2120-406: The host to continue to grow (thus providing more food to the wasp larvae), moult, and evade predators. Ectoparasitic wasps deposit theirs outside the host's body, usually as idiobionts, immediately paralysing the host to prevent it from escaping or throwing off the parasite. They often carry the host to a nest where it will remain undisturbed for the wasp larva to feed on. Most species of wasps attack
2173-435: The host's behaviour. Among the parasitic wasps, Glyptapanteles modifies the behaviour of its host caterpillar to defend the pupae of the wasps after they emerge from the caterpillar's body. The phorid fly Apocephalus borealis oviposits into the abdomen of its hosts, including honey bees , causing them to abandon their nest, flying from it at night and soon dying, allowing the next generation of flies to emerge outside
Mesostoinae - Misplaced Pages Continue
2226-413: The host, such as the co-option of endosymbiotic viruses for compromising host immune defenses . These bracoviruses are often used by the wasps instead of, or in addition to, a venom cocktail. The DNA of the wasp actually contains portions that are the templates for the components of the viral particles and they are assembled in an organ in the female's abdomen known as the calyx. A 2009 study has traced
2279-480: The living bodies of Caterpillars." The palaeontologist Donald Prothero notes that religiously minded people of the Victorian era , including Darwin, were horrified by this instance of evident cruelty in nature, particularly noticeable in the ichneumonid wasps. Parasitoids have inspired science fiction authors and screenwriters to create terrifying parasitic alien species that kill their human hosts. One of
2332-543: The major evolutionary strategies of parasitism emerge, alongside predation. Parasitoidism, in the view of R. Poulin and H. S. Randhawa, is one of six main evolutionary strategies within parasitism , the others being parasitic castrator , directly transmitted parasite, trophically transmitted parasite, vector -transmitted parasite, and micropredator. These are adaptive peaks , with many possible intermediate strategies, but organisms in many different groups have consistently converged on these six. Parasitoids feed on
2385-656: The order Hymenoptera , with about 17,000 recognized species and many thousands more undescribed. One analysis estimated a total between 30,000 and 50,000, and another provided a narrower estimate between 42,000 and 43,000 species. The Braconidae are currently divided into about 47 subfamilies and over 1000 genera, which include Aerophilus , Aleiodes , Apanteles , Asobara , Bracon , Cenocoelius , Chaenusa , Chorebus , Cotesia , Dacnusa , Diachasma , Dimeris , Microgaster , Opius , Parapanteles , Phaenocarpa , Spathius , and Syntretus . These fall into two major groups, informally called
2438-447: The origins of these templates to a 100-million-year-old viral infection whose alterations to its host DNA provided the necessary basis for these virus-like "templates". These viruses suppress the immune system and allow the parasitoid to grow inside the host undetected. The exact function and evolutionary history of these viruses are unknown. Sequences of polydnavirus genes show the possibility that venom-like proteins are expressed inside
2491-419: The parasitoidal fluke's life cycle in its definitive host . Similarly, as strepsipteran parasitoids of ants mature, they cause the hosts to climb high on grass stalks, positions that are risky, but favour the emergence of the strepsipterans. Among pathogens of mammals, the rabies virus affects the host's central nervous system , eventually killing it, but perhaps helping to disseminate the virus by modifying
2544-493: The propagation of the parasitoid. Parasitoids are found in a variety of taxa across the insect superorder Endopterygota , whose complete metamorphosis may have pre-adapted them for a split lifestyle, with parasitoid larvae and free-living adults. Most are in the Hymenoptera , where the ichneumons and many other parasitoid wasps are highly specialised for a parasitoidal way of life. There are parasitoids, too, in
2597-569: The radiation of flowering plants and associated insect herbivores , the main hosts of braconids. Braconids are distinguished from their sister group Ichneumonidae by these character combinations. In Braconidae, vein 2m-cu of the forewing is absent except in the Chilean species Apozyx penyai – this vein is present in 95% of Ichneumonidae. Vein 1/Rs+M of the forewing is 85% present in Braconidae, but absent in all Ichneumonidae. Vein 1r-m of
2650-701: The science website Deep Sea News , writes that there are multiple parallels with parasitoids, though there are in his view more disturbing life cycles in real biology. In his view, the parallels include the placing of an embryo in the host; its growth in the host; the resulting death of the host; and alternating generations , as in the Digenea (trematodes). The social anthropologist Marika Moisseeff argues that "The parasitical and swarming aspects of insect reproduction make these animals favoured villains in Hollywood science fiction. The battle of culture against nature
2703-483: The species. If superparasitism occurs accidentally in normally solitary species the larvae often fight among themselves until only one is left. In another strategy, some parasitoids influence the host's behaviour in ways that favour the propagation of the parasitoid, often at the cost of the host's life. A spectacular example is the lancet liver fluke , which causes host ants to die clinging to grass stalks, where grazers or birds may be expected to eat them and complete
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#17327914398912756-468: The use of a learned, auditory search image. This phenotypic plasticity allows such a highly specialized parasitoid to avoid overspecialization disasters. Interestingly, when receptive females only heard silence the night before testing for preference, they chose the host songs equally, 50/50. This capacity for learning and use of search images paired with a highly specialized morphology and lifestyle (eg. tympana tuned to host sound cues, larviparous) supports
2809-420: Was one of the first naturalists to study and depict parasitoids and their insect hosts in her closely-observed paintings. Parasitoids influenced the religious thinking of Charles Darwin , who wrote in an 1860 letter to the American naturalist Asa Gray : "I cannot persuade myself that a beneficent and omnipotent God would have designedly created parasitic wasps with the express intention of their feeding within
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