The seeds are black grains with one white elaiosome of variable size. The seeds are dispersed through myrmecochory; that is, ants find the seeds and take them into their burrows where they use the elaiosome for food. There the seeds can germinate.
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Seedhead of Leucospermum glabrumThe fruits of Leucadendron have but one seed cavity, that does not open, and contains only one seed, a fruit type called nut. The fruits consist partly of a whitish, fleshy or gelatinous pericarp, a so-called elaiosome, that attracts ants because they contain chemicals that mimic pheromones. After the fruits fall from the plant, mostly Anoplolepis ants gather them, and carry them to their nest by sinking their jaws in the fleshy elaiosome. Ones in the underground nests, the elaiosome is consumed.
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24 Page 71 大百部 da bai bu Stemona tuberosa Lour. Hornets play an important role in seed dispersal by biting off the seed with its elaiosome and then carrying the seed away for about 100 m. There they chew off the elaiosome and abandon the seed which is likely to be taken by ants into their nest.
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The seeds contain an elaiosome that attracts ants, which transport the seeds into their ant colony. This seed transportation is called myrmecochory.
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In myrmecochory, seeds such as those of Chelidonium majus have a hard coating and an attached oil body, an elaiosome, for dispersal by ants.
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Castor seeds have a warty appendage called the caruncle, which is a type of elaiosome. The caruncle promotes the dispersal of the seed by ants (myrmecochory).
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A diaspore of seed plus elaiosome is a common adaptation to seed dispersal by ants (myrmecochory). This is most notable in Australian and South African sclerophyll plant communities. Typically, ants carry the diaspore to their nest, where they may eat the elaiosome and discard the seed, and the seed may subsequently germinate. Achenes of a dandelion (Taraxacum) A diaspore of seed(s) plus fruit is common in plants dispersed by frugivores.
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The fruits are collected by native ants for the pale edible elaiosome, which is eaten in the underground nest, where the seeds remain until they germinate after an overhead fire.
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Seeds have a hard black-brown testa (i.e. seed coat) with a pleurogram, visible as a closed or almost closed O-shaped line. Some phyllodinous species have a colourful aril or elaiosome on the seed.
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Here the elaiosome is consumed. The remaining seed is big, slick and hard and the ants cannot remove it. This way the seeds are safe from seed- eaters and fire. This seed dispersal strategy is called myrmecochory.
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The ripened fruit falls to the ground approximately two months after flowering. Native ants carry them to their underground nests to eat the elaiosome. The seed remains dormant until a fire has destroyed the above- ground biomass.
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Bees and beetles also visit the flower heads but do not touch the pollen presenters and so do not pollinate. The seeds are covered by a fleshy coating that attracts ants, that is called elaiosome. The seeds fall about two months after flowering to the ground, where native ant species carry them to their nests, and the elaiosome is eaten. The remaining seed is smooth and hard and too big for the ants jaws to remove, and so remain safe from being eaten by rodents and birds and overhead fires.
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The seed dispersal by birds and other mammals are able to attach themselves to the feathers and hairs of these vertebrates, which is their main method of dispersal. Seed dispersal by ants (myrmecochory) is a dispersal mechanism of many shrubs of the southern hemisphere or understorey herbs of the northern hemisphere. Seeds of myrmecochorous plants have a lipid-rich attachment called the elaiosome, which attracts ants. Ants carry such seeds into their colonies, feed the elaiosome to their larvae and discard the otherwise intact seed in an underground chamber.
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Once the elaiosome is consumed the seed is usually discarded in underground middens or ejected from the nest. Although diaspores are seldom distributed far from the parent plant, myrmecochores also benefit from this predominantly mutualistic interaction through dispersal to favourable locations for germination as well as escape from seed predation.
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A double-flowered variety occurs naturally. The flowers appear from late spring to summer, May to September (in UK), in umbelliform cymes of about 4 flowers. The seeds are small and black, borne in a long, cylindrical capsule. Each has an elaiosome, which attracts ants to disperse the seeds (myrmecochory).
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Melampyrum pratense, the common cow-wheat, is a plant species in the family Orobanchaceae. The seed of the plant has an elaiosome, which is attractive to wood ants (Formica spp.). The ants disperse the seeds of the plant when they take them back to their nests to feed their young.Puplett, D. Symbiosis.
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Serruria fasciflora is specifically adapted for pollination by flies, as they have a very sweet scent. The common pin spiderhead survives the regular wildfires in fynbos through its seeds. The fruits fall to the ground about two months after flowering. These have a fleshy covering (or elaiosome) that secretes a pheromone and attracts ants.
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The American Naturalist, 131(1): 1-13. effectively directing the dispersal of seeds to desirable sites. For example, myrmecochores can influence seed fate by producing rounder, smoother diaspores that inhibit ants from re-dispersing seeds after elaiosome removal. This increases the likelihood that seeds will remain underground instead of being ejected from the nest.
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On occasion, the night temperature may drop below 0 °C. The large flowers of the grey-leaf fountain pincushion are mostly pollinated by Cape sugarbirds. The mature fruits fall to the ground about two months after flowering. Here they are gathered by native ants, which carry them to there underground nest, where the elaiosome is eaten.
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The stigmas are recurved at the tips. It is distinguished from other sessile-flowered Trillium species, such as Trillium sessile, by its reflexed sepals. The fruit is green, sometimes streaked with purple or white, with six well-developed ridges. The seeds have an oil-rich structure called an elaiosome, which promotes dispersal by ants and other foraging insects.
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Occasionally plants are found with green markings on the outer surface of the outer tepals. The six long, pointed anthers open by pores or short slits. The ovary is three-celled, ripening into a three-celled capsule. Each whitish seed has a small, fleshy tail (the elaiosome) containing substances attractive to ants which distribute the seeds.
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Trillium sessile is most common in rich, moist woods but also can be found in limestone woods, flood plains, and along fence rows. It is persistent under light pasturing. The foul smelling flowers attract its primary pollinators, flies and beetles.Missouri Plants: T. sessile The seeds have an elaiosome which attracts ants and wasps such as Vespula species.
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Myrmecochory, literally translated as "ant- dispersal," is the collection and dispersal of seeds by ants. Ants disperse more than 30% of the spring-flowering herbaceous plants in eastern North America. Both the plant and the ant benefit in this scenario. The ants are provided with an elaiosome, a detachable food body found on the surface of the seed.
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Elaiosomes have diverse compositions, usually high in lipids and fatty acids, but also containing amino acids, sugars, and protein. The ants remove the elaiosome once the seed has been transported to the colony. As a result, the seeds are safely placed in nutrient-rich substrate protected from predators, benefiting the plant with optimum establishment conditions for its seed.
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Seeds of D. viscosa have very small funicular aril, and are harvested by Pheidole sp. of ants and deposited in middens outside the nest after the elaiosome has been consumed. Bayesian MCMC estimation of Dodonaea phylogeny supported the hypothesis that two species of Cossinia are sisters to Diplopeltis and Dodonaea. Nevertheless, Diplopeltis is identified as a paraphyletic group.
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Incised fumewort is an introduced species in the United States, with populations in New York, Pennsylvania, Maryland, Virginia, West Virginia, North Carolina, Tennessee, and the District of Columbia. The first reported populations were found in Bronx and Westchester Counties in 2005 and 2014. The plant can readily escape cultivation; it spreads from seeds explosively ejected from the fruit. The seed contains an elaiosome, which attracts dispersing ants.
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In botany, a diaspore is a plant dispersal unit consisting of a seed or spore plus any additional tissues that assist dispersal. In some seed plants, the diaspore is a seed and fruit together, or a seed and elaiosome. In a few seed plants, the diaspore is most or all of the plant, and is known as a tumbleweed. Diaspores are common in weedy and ruderal species.
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The seeds are kidney-shaped, with a faint netlike pattern. Each one has a fleshy organ called an elaiosome that attracts ants. Dutchman's breeches is one of many plants whose seeds are spread by ants, a process called myrmecochory. The ants take the seeds to their nest, where they eat the elaiosomes, and put the seeds in their nest debris, where they are protected until they germinate.
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Large insects, such as monkey beetles also visit the flower, but do not necessarily brush along the pollen presenters and may be inefficient as pollinators. The fruits are ripe approximately two months after flowering and subsequently fall to the ground. These are collected by ants that carry them underground into their nests. Here, the soft, pale elaiosome is eaten, and the hard, smooth seed remains underground.
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Bloodroot is one of many plants whose seeds are spread by ants, a process called myrmecochory. The seeds have a fleshy organ called an elaiosome that attracts ants. The ants take the seeds to their nest, where they eat the elaiosomes, and put the seeds in their nest debris, where they are protected until they germinate. They also benefit from growing in a medium made richer by the ant nest debris.
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In late summer three capsuled ovaries split open releasing seeds that have attached food bodies called (elaiosome) which are attractive to ants that collect and redistribution the seeds. The Latin specific epithet grandiflora means "large flowered". This plant differs from Uvularia sessilifolia in that the leaves of the latter grow from the stem and its flowers are smaller. U. grandiflora also differs from Uvularia perfoliata, which occurs in eastern North America.
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The oval-leaf pincushion is pollinated by insects, including bees and flies. When the fruits are ripe about two months after flowering, they fall to the ground. Here they are gathered by ants who are attracted to a pale fleshy ant loaf (or elaiosome) and carry them to their underground nests where the ant loaf is eaten, but the seeds remain safely stored. This seed dispersal strategy is known as myrmecochory.
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Erythronium americanum does not reproduce very effectively via sexual reproduction with only 10% of pollinated flowers developing seeds. The fruit is a 12 to 5 mm long capsule that is held off the ground by the flower stalk. E. americanum is a myrmecochorous plant, meaning that ants help disperse the seeds and reduce seed predation. To make the seeds more appealing to ants they have an elaiosome which is a structure that attracts ants.
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Ploidy of systems such as the salivary gland, elaiosome, endosperm, and trophoblast can exceed this, up to 1048576-ploid in the silk glands of the commercial silkworm Bombyx mori. The chromosome sets may be from the same species or from closely related species. In the latter case, these are known as allopolyploids (or amphidiploids, which are allopolyploids that behave as if they were normal diploids). Allopolyploids are formed from the hybridization of two separate species.
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The seed is covered by a soft, sweet and fatty layer that emits pheromones (called elaiosome) that is coveted by ants. Indigenous ant species collect them and take them to their underground nests, where they eat the ant bread. The ants cannot move the large hard and slick seed when the ant bread is removed and so remains underground, safe from being eaten and fire. This seed dispersal strategy is called myrmecochory.
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This activity is probably encouraged by the presence of a tiny white food body (elaiosome) on the tip of the seed that may be attractive to the ants. These seed-carrying ants may play an important role in the survival and germination of the seeds of P. perfoliata. Local bird populations are important for dispersal under utility lines, bird feeders, fence lines and other perching locations. Other animals observed eating its fruits are chipmunks, squirrel and deer.
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Features of the perigynium may aid in seed dispersal, such as a surface that clings to fur or skin or a shape that enables dispersion via wind or water. Seed dispersal by animals such as ants (myrmechory) has been recorded, as some species of sedges have developed elaiosomes at the base of the perigynia. Ants carry the perigynium back to the nest, use the elaiosome for food, and the seed germinates away from the parent plant.
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Many ant-dispersed seeds have special external structures, elaiosomes, that are sought after by ants as food. A convergence, possibly a form of mimicry, is seen in the eggs of stick insects. They have an edible elaiosome-like structure and are taken into the ant nest where the young hatch. A meat ant tending a common leafhopper nymph Most ants are predatory and some prey on and obtain food from other social insects including other ants.
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However, the most common visitors to the flowers are small beetles of the genus Meligethes – often there are up to 12 or more pollen-covered individuals in a single flower. The beetles also fly from flower to flower and, at least theoretically, are well suited as pollinators.Dietmar Aichele, Heinz-Werner Schwegler: The flowering plants of Central Europe , Franckh-Kosmos-Verlag, 2nd revised edition 1994, 2000, Volume 3, The seeds have an elaiosome and are spread by ants (myrmecochory).
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Visits of the orange-breasted sunbird are less effective because this species sits below the inflorescence and so largely avoids the pollen presenters. After the fruits have fallen, native ants collect these and carry them to their underground nests. Here, they eat the elaiosome, and the hard grey seeds remain protected against being eaten and fire, until they germinate after an overhead fire and subsequent rains. Like most shrubs in its habitat, the marsh pagoda is short-lived.
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Here, the ants eat the pale, soft outer layer called elaiosome, leaving the smooth and hard seed because it is too big to fit between their jaws. The seeds so remain buried, safe from being consumed by rodents, and protected from the overhead wildfires that destroy most of the standing vegetation every one or two decades. After the fire, the seeds germinate, and are able to grow quickly, thanks to the absence of competition and a relatively good supply of nutrients.
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The stamens are about ⅓× as long as the lateral petals, orange to golden brown in color, with the style just reaching beyond them. The fruit is a small, yellowish and hairless, 4–6 mm (0.16–0.24 in) long capsule with three parts, that splits when ripe, eventually squeezing out the 1–2 mm (0.04–0.08 in) long seeds with such a force that they shoot away. The seeds have a clear, spongy elaiosome. In Zambia the plants flower from October to March.
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After the fruits have fallen to the ground, they are collected by native ants and carried to their nests, where the so-called elaiosome is eaten, while the seed remains underground. The elaisome is a pale, fleshy and tasty part of the fruit, that also contains a pheromone particularly attractive to ants. Here, the seed is protected against consumption by rodents and birds. After an above ground fire has killed the vegetation, and subsequent rain, the seeds germinate and locally revive the species.
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In the middle of the falls, there is a row of short hairs called the 'beard', which is mostly orange, yellow, or dark-tipped on a cream ground. After the iris has flowered, it produces a seed capsule. The seeds are 3 mm in size and the wind disperses them from the seed capsules. The elaiosome (fleshy coating) of seeds of the iris are rolled by the wind along the soil surface near the plant and collected later by ants.
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Leaves are lobed and large, while the white flowers occur in cymes, producing a spiny 3-seeded capsule with seeds rich in fats and proteins, resembling those of Ricinus communis. Its carunculate seeds are usually dispersed by ants (myrmecochory) attracted by the edible elaiosome. The entire plant is covered in stinging hairs, and has a native range covering Central and South America, being found in Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru and Venezuela. Cnidoscolus urens is monoecious and self-compatible.
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In seeds given to colonies, 80% of Sanguinaria canadensi seeds were scarified and 86% of Viola rotundifolia seeds were destroyed. Small percentages of longleaf pine (Pinus palustris) seeds deposited by workers successfully germinate, thus providing evidence that red imported fire ants help the movement of seeds in the longleaf pine ecosystem. Elaiosome-bearing seeds are collected at a higher rate in contrast to nonelaiosome-bearing seeds and do not store them in their nests, but rather in surface trash piles in the mound vicinity. A social chromosome is present in the red imported fire ant.
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The long-stalk spiderhead is considered a near threatened species, because over the last 60 years about 30% of its habitat was lost to urban expansion, agriculture and afforestation, and competition by invasive plant species. Further population decrease is expected due to climate change. The expansion of naturalised alien ants is also a threat, since unlike native ants, they didn't carry the fruits to their underground nest before they eat the elaiosome and so fail to protect the seeds against the wildfires that naturally occur in the fynbos.
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The birds sit on the flower head and stick their long bills into perianth tubes and so bring their heads and necks in contact with the pollen presenters. Although the flowers are also visited by insects, these do not touch the pollen presenters so do not contribute to the pollination. The seeds are covered in a pale fleshy coating called elaiosome that attracts ants. About two months after flowering, the seeds are ripe and get released from the flower heads, and native ants gather them and carry them to their underground nests.
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Worker collecting a small flower The green-head ant is a diurnal species that is active throughout the day, quickly foraging on either the ground or vegetation. They are scavengers, predators and seed-eaters, generally having a broad diet of animal material, insects, small arthropods, honeydew from sap- sucking insects and seeds. The workers usually prey on beetles, moths and termites, using their stingers to kill them by injecting venom. The removal of the capitula (structure similar to an elaiosome) from Eurycnema goliath eggs reduces the chances of them being collected by green-head ants that carry them back into their nests.
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Ants may play an important role in the dynamics of plant communities by acting either as seed dispersal agents or as seed predators, or both. During the day, these ants search the savannas for vegetation and plant seeds, and carry them along back to their nest. The two main mechanisms through which ants disperse seeds are myrmecochory, or seed dispersal mediated by the elaiosome, i.e., a lipid-rich seed appendage that mainly attracts non-granivorous ants and provides rewards for seed dispersal, and diszoochory, or seed dispersal performed by seed- harvesting ants that is not mediated by any particular seed structure.
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It consists of one carpel and contains a single pendulous ovule. At the base of the ovary are four linear or awl-shaped scales of long that secrete a copious amount of nectar. The indehiscent fruit consists of one cavity, containing one oval to globe-shaped seed of long, with a broad indent where it was attached, hairless or covered with a fine powder and generally partially covered by a pale elaiosome. The sixteen Leucospermum species that have been analysed are all diploids having twelve sets of homologue chromosomes (2n=24), which is consistent with the rest of the subtribe Proteinae.
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Rourke erected several sections in 1970, among which Xericola, to which he assigned L. alpinum including a subspecies amoenum, L. obtusum including a subspecies albomontanum, as well as L. secundiflorum. In 1984, he erected a new genus Vexatorella to which he moved these taxa, with the exception of L. secundiflorum, that he included in the section Diastelloidea. The name of the genus Leucospermum is compounded from the Greek words λευκός (leukos) meaning white, and σπέρμα (sperma) meaning seed, so "white seed", which is a reference to the pale elaiosome surrounding the seeds. Species within the genus are commonly known as pincushions.
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In addition to the three basic seed parts, some seeds have an appendage, an aril, a fleshy outgrowth of the funicle (funiculus), (as in yew and nutmeg) or an oily appendage, an elaiosome (as in Corydalis), or hairs (trichomes). In the latter example these hairs are the source of the textile crop cotton. Other seed appendages include the raphe (a ridge), wings, caruncles (a soft spongy outgrowth from the outer integument in the vicinity of the micropyle), spines, or tubercles. A scar also may remain on the seed coat, called the hilum, where the seed was attached to the ovary wall by the funicle.
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These seeds are most typically dispersed by ants, which is called myrmecochory, but yellow jackets (Vespula vulgaris) and harvestmen (order Opiliones) have both been observed dispersing the seeds at lower frequencies. Insect dispersal is aided by the presence of a conspicuous elaiosome, an oil-rich body attached to the seed, which is high in both lipids and oleic acid. The oleic acid induces corpse-carrying behavior in ants, causing them to bring the seeds to their nesting sites as if they were food. As ants visit several colonies of the plant, they bring genetically variable seeds back to a single location, which after germination results in a new population with relatively high genetic diversity.
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Eggs of various phasmid species (not to scale) Many species' eggs bear a fatty, knoblike capitulum that caps the operculum. This structure attracts ants because of its resemblance to the elaiosome of some plant seeds that are sought-after food sources for ant larvae, and usually contribute to ensuring seed dispersal by ants, a form of ant-plant mutualism called myrmecochory. The ants take the egg into their nest underground and can remove the capitulum to feed to their larvae without harming the phasmid embryo. There, the egg hatches and the young nymph, which initially resembles an ant (another instance of mimicry among Phasmatodea), eventually emerges from the nest and climbs the nearest tree to safety in the foliage.
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Some species, such as the young nymphs of Extatosoma tiaratum, have been observed to curl the abdomen upwards over the body and head to resemble ants or scorpions in an act of mimicry, another defense mechanism by which the insects avoid becoming prey. The eggs of some species such as Diapheromera femorata have fleshy projections resembling elaiosomes (fleshy structures sometimes attached to seeds) that attract ants. When the egg has been carried to the colony, the adult ant feeds the elaiosome to a larva while the phasmid egg is left to develop in the recesses of the nest in a protected environment. When threatened, some phasmids that are equipped with femoral spines on the metathoracic legs (Oncotophasma martini, Eurycantha calcarata, Eurycantha horrida, Diapheromera veliei, Diapheromera covilleae) respond by curling the abdomen upward and repeatedly swinging the legs together, grasping at the threat.
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