Researchers should be careful when studying termites. At Auburn University's Extension Hall, entomologists studying termites and other insects found that their building had been plagued for 15 years by an infestation of native Eastern subterranean termites (R. flavipes). (Senticrom Webpage, 1993)
R. flavipes are by far the most destructive of all termites (Su and Scheffrahn, 1990). They are notorious for their destruction of manmade wood products. Billions of dollars annually go to damage repair and treatment (Su and Scheffrahn, 1990). Homes and buildings can be consumed by R. flavipes as their massive colonies expand.
"Termites are not all bad. In natural settings, they fulfill a vital function in breaking down the forest debris into raw materials that nourish new trees. Termites get into difficulty because they cannot tell the difference between a fallen tree and wood that is being used by humans" (Knowledge Book Enclyclopedia, 1997). By converting existing biomass to biomass that other animals can consume, termites support a large proportion of temperate vertebrate biodiversity, including many species of amphibians, reptiles, birds, and ground foraging insectivorous mammals. Termites are effective decomposers. Although not in widespread use now, they could be used to degrade damp rotten wood, wood chips, mill waste, structural rubble waste or other wood waste. They are relatively easy to handle and maintain, and could play a beneficial role in reducing landfill space.
Termites ingest wood. They cannot, however, digest wood fibers. Instead, "Termites rely on single-celled animals -- protozoa -- that live in their gut to digest the hard components of wood, freeing up the cellulose that nourishes them." (Grady, 1996) They live off of the by-products of this process.
Plant Foods: roots and tubers; wood, bark, or stems
Primary Diet: herbivore (Lignivore)
R. flavipes is found throughout the eastern United States, as faro north as the Mississippi and as far south as Mexico. It has been accidentally introduced to southern France.
Biogeographic Regions: nearctic (Native ); palearctic (Introduced )
In the north, colony populations of R. flavipes can reach up to 1-10 million. In addition, these termites may forage on territories up to several thousand square meters (Myles, 1998) Of the termites, only R. flavipes and its cousin, R. tibialis, build "shelter tubes" over foundations or through cracks in timber. They build these with soil particles, saliva, and feces. These tubes require constant moisture and soil contact to sustain the colony (Myles, 1998). The subterranean termites, themselves, must have contact with the soil in order to survive (Krishna, 1989). They may also live in giant termite mounds made of mud and ground mass. It is possible for termites to adjust the level of their nest to optimum moisture and stability levels.
Terrestrial Biomes: savanna or grassland ; forest
Termites are thought to have diverged early in insect evolution. Ancestors had gradual metamorphosis and the ability to fold their wings over their backs. Their body plan is simple, while their social behavior is advanced. Termites are hemimetabolous, medium sized, polymorphic (having more than one form) social insects. They have biting mouthparts, and antennae comprising 9 to 30 segments. The alate forms (winged primary reproductives) have four almost equal wings and compound eyes; however, the sterile workers and the secondary reproductives have no or greatly reduced compound eyes.
Each member of the R. flavipes colony (workers, soldiers, and kings & queens) looks different. R. flavipes soldiers are slightly bigger than workers and have enlarged and darkened orange head capsules. The workers are creamy-white and are approximately 5-6mm in length (Myles, 1998). As queens reproduce, they become massive creatures of up to 9cm long. The kings are cream colored like the workers, and look like tiny maggots compared to the queen. (Benavides, 1998).
Other Physical Features: ectothermic ; bilateral symmetry
R. flavipes reproduce in swarms. Swarming occurs when a colony reaches a certain size and when temperature and moisture levels are favorable. Usually this occurs on warm days after rainfall. Some researchers speculate that swarming occurs after rainfall because the ground is moist, which make it easier to create a new nesting site (Benavides, 1988). Alates, winged swarmers, fly from their native nest until they hit a "fracture point" in the air. This causes their wings to fall off (Benavides, 1998) This flight is not considered a mating flight because R. flavipes are only sexually attracted to their mates after their wings have broken off (Light, 1922). Once they find a mate, which takes a while because the female is choosy, they walk together to find a suitable nesting site. They mate after they've built a "nuptial chamber" in their new nest (Benavides, 1998). At her peak a queen will lay an egg every 3 seconds, or 30,000 a day. She will lay 10's of millions of eggs during her life (Ramel, 1998). The queen does not store a lifetime supply of sperm, so R. flavipes males remain as consorts to the queen (Benavides, 1998).
Die Gelbfüßige Bodentermite (Reticulitermes flavipes) ist eine Termitenart aus der Familie der Rhinotermitidae. Sie wird vier bis fünf Millimeter lang und zerstört verbautes Holz.
Die Kolonien der Gelbfüßigen Bodentermite können 20.000 bis 5 Millionen, im Durchschnitt 300.000 Arbeiter enthalten. Sie werden im Erdboden unterhalb der Frostgrenze angelegt. Nebennester können auch über dem Erdboden liegen. Diese müssen jedoch Kontakt zu einer Feuchtigkeitsquelle wie zum Beispiel einem Leck in einem Wasserrohr haben. Oft werden Schutzröhren zwischen der Kolonie und den Nahrungsquellen angelegt.[1]
Die Gelbfüßige Bodentermite kommt im Osten Nordamerikas und nördlich bis nach Ontario, Kanada und nach Süden bis nach Key Largo in Florida vor. Sie wurde in Holz aus Nordamerika per Schiff nach Deutschland eingeschleppt. Sie wurde erstmals 1937 in Hamburg und 1966 in München nachgewiesen.[2]
Die Gelbfüßige Bodentermite kann alle Materialien, die aus Zellulose bestehen, als Nahrung verwerten, also Holz, Papier und Baumwolle. Mitunter frisst sie die Wurzeln von Bäumen und Sträuchern an.
Die hypermastigoten Flagellaten Spirotrichonympha sp. und Trichonympha sp. leben ausschließlich in dieser Termitenart.[3] Sie spalten die Zellulose und machen sie so erst für die Termite verwertbar.
Die Gelbfüßige Bodentermite (Reticulitermes flavipes) ist eine Termitenart aus der Familie der Rhinotermitidae. Sie wird vier bis fünf Millimeter lang und zerstört verbautes Holz.
Reticulitermes flavipes, the eastern subterranean termite, is the most common termite found in North America.[1] These termites are the most economically important wood destroying insects in the United States and are classified as pests.[1] They feed on cellulose material such as the structural wood in buildings, wooden fixtures, paper, books, and cotton. A mature colony can range from 20,000 workers to as high as 5 million workers and the primary queen of the colony lays 5,000 to 10,000 eggs per year to add to this total.[1]
The eastern subterranean termite (R. flavipes) is the most widely distributed Reticulitermes species.[2] It occurs throughout the eastern United States, including Texas,[3] and can be found as far north as southern Ontario.[4] In 2006, R. flavipes was also recorded in Oregon,[5] on the West coast of the United States.
Reticulitermes santonensis in France is now understood to be a synonym of R. flavipes.[2] The species is now believed to originate in the southeastern United States[6][7] and to be exotic or invasive in southern Canada,[4][6] Europe (France,[6][7] Germany[6][8]), South America (Uruguay, Chile),[2][6] and the Bahamas.[9][6] An infestation of unknown origin was also discovered in an Italian house in 2008.[10]
Eastern subterranean termites, like other social insects, share resources and divide labor based on a caste system.[1] They live in loosely associated societies called colonies which are composed of both males and females. The termites in the colony are generally organized into the worker caste, the soldier caste, and the reproductive caste.[1]
Workers are about 3 mm long and are blind, wingless, soft-bodied, creamy white to grayish-white with a round head.[11] They make up the majority of the termites that actually eat the wood. They are sterile and forage for food and water, construct and repair shelter tubes, feed and groom other termites, care for eggs and young, and participate in colony defense.[12]
Soldier termites are also wingless and resemble workers except that they have a large, rectangular, yellowish-brown head with long black mandibles. The soldiers’ primary function is colony defense [1] and the mandibles are mainly used for crushing enemy ants which may invade the colony. Additionally, R. flavipes has a fontanelle (frontal gland pore) on the forehead from which it secretes a blend of terpenoid compounds. These secretions are synthesised de novo and are also used to defend the colony from predators such as ants.[13] The soldier caste only makes up 1 to 2% of the entire colony. The soldiers are not capable of feeding themselves and rely on the worker termites to provide them with regurgitated food.[1]
Soldiers have been found to protect alates as they begin to leave the nest. Perhaps correspondingly, soldiers populations reach their highest in the Spring as temperatures increase.[14][15]
Immature termites on the sexual, or reproductive, line are called nymphs and can be distinguished from workers by the presence of wing buds. Under natural conditions, the work that they do in the nest is negligible compared to that done by workers. They can feed themselves, but there is debate over how long (over how many instars) they retain this ability.[16]
Alates (from the Latin ālātus, "having wings") are winged, sexually mature adults that are capable of dispersal and outbreeding. In R. flavipes, they are 8.5-10mm in length to the tips of their wings[17] and have compound eyes, ocelli, and a dark brown to black fully sclerotized cuticle.[18] As the species name suggests (flāvī, "yellow" + pēs, "foot"), the tarsi are yellowish.[19] To distinguish R. flavipes from similar species (at least in the United States), the position of the ocelli can be used: looking at the head from the side, the distance between the ocellus and the nearest compound eye is at least as large as the diameter of the ocellus.[17][19]
Alates always develop from nymphs, with the last nymphal stage characterised by particularly long wing buds. After leaving their nests and swarming, male and female alates pair, shed their wings, begin excavating a new nest, and mate. From this point onward, they are called kings and queens, dealates, or primary reproductives.[16]
Secondary reproductives, or neotenics, develop from either the reproductive line (brachypterous neotenics) or, in rare cases, the worker line (ergatoids). Ergatoids are the only members of the reproductive caste that have neither wing buds nor wings. Like workers, soldiers, and nymphs, they are eyeless. Ergatoids are seldom found in nature.[16]
Brachypterous neotenics, which are common in the French population of R. flavipes (formerly R. santonensis), and possibly other populations as well, develop from nymphs via a nymph-like pre-brachypterous neotenic stage.[16] They can be distinguished from nymphs by their shorter wing buds (brachy-, "short" + -pterous, "having wings"), darker pigmentation, slight sclerotization, and longer abdomens. Like alates, brachypterous neotenics also have compound eyes and ocelli. Female neotenics lay eggs at a lower rate than queens, but when present in large numbers, they may play a significant role in the growth of the colony.[16]
R. flavipes are opportunistic, and a newly hatched termite can develop into any of a number of castes. At first, it becomes a worker termite and is most likely to remain one for its entire lifespan. Molting can change the worker into a pre-soldier and subsequently, a soldier. The soldier caste is a terminal stage which can no longer molt.[12]
R. flavipes also molts into nymphs, which are the precursors of winged adult termites called alates which are sexually mature. Nymphal termites are non terminal and can revert to the worker stage. These reverted nymphs are called pseudergates. Nymphs and workers can also develop into secondary and tertiary neotenic reproductives respectively.[12]
Because termites are social insects, they share many of their tasks. This can be seen throughout the caste system, where different castes take on different responsibilities for the betterment of the whole colony. R. flavipes cooperate in the rearing of young and also share their resources with the nest.[12]
Swarming is the sudden, dramatic appearance of R. flavipes alates in the daytime from February to April. After this behavior male and female alates lose their wings, pair up, and form new colonies.[12]
R. flavipes is mobile throughout its life and no permanent central nest area exists. Therefore, all termite castes can be found in any of the different sites occupied by a colony. Their activity is determined by food, moisture and temperature, and movement is usually driven by one of these necessities. Termites feed on anything made of or containing cellulose, but can tunnel into non-cellulose containing material to gain access to their destination. This behavior can be destructive to human activities.[12]
The first person to observe and formally describe symbiotic flagellates in R. flavipes was the American paleontologist Joseph Leidy. In 1877, he reported his findings to the Academy of Natural Sciences of Philadelphia, describing three new species which he mistakenly took to be parasitic ciliates: Trichonympha agilis, Pyrsonympha vertens, and Dinenympha gracilis.[20]
Prof. LEIDY remarked that in seeking small animals beneath stones and fragments of wood in our forests, observing the very common White Ant, Termes flavipes, he noticed that the intestine of the insect, seen in the translucent abdomen, was distended with brown matter. Feeling curious to learn the exact nature of this matter, he was surprised to find that it consisted largely of infusorial and other parasites, mingled with minute particles of decayed wood. In many instances the parasites are so numerous as to make up the greater portion of the bulk of the intestinal pulp. Every individual he had examined, of workers, soldiers, and winged forms, was infested with the parasites, which may be estimated by millions.
— Proceedings of the Academy of Natural Sciences of Philadelphia (1877)[20]
So far, least 9 genera and 11 species of symbiotic flagellate have been found in the R. flavipes hindgut:[21][22]
A 2003 study that focused on oxymonad flagellates found evidence of at least one additional undescribed Dinenympha species. They also found what they believe is an undescribed "second" Pyrsonympha species in addition to P. vertens. The authors question whether P. major, which was first described in Reticulitermes hesperus, is truly found in R. flavipes and consider it a case of mistaken identity.[23]
Flagellates are a feature of all termite families except Termitidae, the so-called "higher termites". They are found exclusively in the hindgut, especially the paunch, an enlarged section of the hindgut with an anaerobic interior that serves as a fermenter. In R. flavipes, wood eaten by the termite is first broken up with the mandibles, treated with host endoglucanases from the salivary glands,[24] ground up into small particles in the gizzard, and then treated with additional host cellulases in the midgut, freeing glucose for immediate absorption. It then passes into the paunch, where flagellates take up the partly-digested wood particles through endocytosis.[25] The flagellates break lignocellulose (xylan or cellulose) down into simple sugars, which they ferment for their own energy needs, producing CO2, H2, and short-chain fatty acids such as acetate as waste products. The short-chain fatty acids (which are also produced by homoacetogenic gut bacteria from CO2 and H2) can be directly absorbed by the termite host.[25][26] The vast majority of digestion takes place in the paunch: almost all xylanase activity, just over one quarter of the endoglucanase activity, and almost two thirds of the exoglucanase activity in the R. flavipes digestive system is localised in the hindgut and attributed to gut flagellates.[24]
Although this is an obligate symbiosis, newly hatched larvae do not have gut flagellates. These are acquired when the larvae are fed with flagellate-containing anal fluids from other members of the colony (proctodeal trophallaxis). Proctodeal trophallaxis is also used to replenish flagellates and other gut symbionts after each moult.[25]
Most bacterial species in the termite gut are difficult or impossible to culture,[25][27] so methods like 16S ribosomal RNA sequencing are used to identify which groups are present. One such analysis of R. flavipes worker guts uncovered representatives of the Endomicrobia (Elusimicrobiota), Actinomycetota, Pseudomonadota, Bacillota, Bacteroidota, and Spirochaetota.[27] The dominant bacterial taxon in the core gut microbiome is the genus Treponema (Spirochaetota), which accounted for approximately 32% of sequences in another 16S rRNA study.[28] The same study identified Endomicrobia (phylum:Elusimicrobiota), which are predominant endosymbionts several protozoa in the termtie gut.[28] Artificial defaunation of Reticulitermes species by force-feeding on starch or starvation leads to a loss of flagellates and, by association, these endosymbiotic Endomicrobia, and an increase in abundance of free-living relatives.[29] A rare free-living member of this class, Endomicrobium proavitum, the first Endomicrobia species to be cultured and named, was isolated from sterile-filtered gut homogenates from defaunated (starch-fed) R. flavipes workers. It is believed to play a role in nitrogen fixation.[30]
While some gut bacteria live free in the gut lumen or attached to the gut wall, many others live in close association with flagellates. These include uncultured members of Endomicrobia (Elusimicrobiota) and other taxa that live as cytoplasmic symbionts, as well as epibiotic symbionts that attach to the outer surface of cells. In R. flavipes, cytoplasmic symbionts have been identified in flagellates such as Trichonympha agilis (Hypermastigida) and Pyrsonympha vertens (Oxymonadida).[31] The latter is also characterised by spirochaete epibiotic symbionts.[32] In other termite species, members of the spirochaete genus Treponema have been identified as endo-[33] and ectosymbionts[34] of flagellates: similar associations may explain Treponema's dominance in the R. flavipes gut.[28]
Archaea isolated from the R. flavipes hindgut include the H2- and CO2-utilizing methanogens Methanobrevibacter cuticularis and curvatus.[35] These two species are believed to be the dominant methanogens in R. flavipes and are found in the peripheral, microxic region of the hindgut, on or in close proximity to the gut wall, where they are sometimes attached to filamentous prokaryotes.[35]
Although there is a core microbiome shared among castes and colonies, the alate caste gut is characterised by a significantly lower abundances of bacteria in the genus Treponema (Spirochaetota) and the class Endomicrobia (Elusimicrobia) compared to workers and soldiers.[28] Flagellates in the class Parabasalia and the order Oxymonadida are also significantly less abundant in the alate gut, with the latter significantly reduced in dealates as well.[28]
Along with Reticulitermes virginica, R. flavipes is responsible for 80% of the $2.2 billion spent annually in the United States on termite control.[36] Termites feed on wood cellulose, meaning that their presence in human made structures often goes unnoticed for lengthy periods of time. A termite infested timber will appear structurally sound from the outside, while inside it will have a honeycombed appearance. To detect the presence of R. flavipes the observer can test the integrity of the wood by tapping it with a screwdriver. If present, R. flavipes is found at, near or below ground level. Trim work, sub flooring, flooring, and the structural timbers are the areas of a building most susceptible to termite damage. The Eastern subterranean termite is considered a serious economic timber pest and it is estimated that in high activity areas more than 1 in 5 homes have been or will be attacked.[37]
Termite control methods include: physical barriers, chemical treatments, and physical treatments (such as heat, freezing, electrocution and microwave irradiation).[38]
Structural damage to buildings is not R. flavipes’ only impact on humans. Termites also play a critical role in the decomposition of organic matter in natural communities. Without termites, the accumulation of dead organic matter on the forest floor would become detrimental to integrity of that forest. The benefits provided by R. flavipes in terms of their contribution to environmental regulation may far outweigh the disadvantages they pose.[39]
Reticulitermes flavipes, the eastern subterranean termite, is the most common termite found in North America. These termites are the most economically important wood destroying insects in the United States and are classified as pests. They feed on cellulose material such as the structural wood in buildings, wooden fixtures, paper, books, and cotton. A mature colony can range from 20,000 workers to as high as 5 million workers and the primary queen of the colony lays 5,000 to 10,000 eggs per year to add to this total.
Reticulitermes flavipes (anciennement R. santonensis), le termite de Saintonge ou termite à pattes jaunes, est l’espèce du genre Reticulitermes la plus répandue sur terre.
Elle est originaire d'Amérique du Nord et est invasive au Canada[1], en Californie, en Uruguay et aux Bahamas[2], en France[3],[4], au Chili[5], en Allemagne[6], en Italie[7] et en Autriche où elle a été décrite pour la première fois[8]. Les analyses phylogéographiques des populations natives et introduites de R. flavipes ont révélé que la grande majorité des populations introduites proviennent du Sud-Est des États-Unis et plus précisément de la Louisiane[9].
Reticulitermes flavipes (anciennement R. santonensis), le termite de Saintonge ou termite à pattes jaunes, est l’espèce du genre Reticulitermes la plus répandue sur terre.
Elle est originaire d'Amérique du Nord et est invasive au Canada, en Californie, en Uruguay et aux Bahamas, en France,, au Chili, en Allemagne, en Italie et en Autriche où elle a été décrite pour la première fois. Les analyses phylogéographiques des populations natives et introduites de R. flavipes ont révélé que la grande majorité des populations introduites proviennent du Sud-Est des États-Unis et plus précisément de la Louisiane.
Reticulitermes flavipes (Kollar, 1837) é uma espécie de térmita,[1][2][3] do tipo subterrâneo da família Rhinotermitidae,[4][5] originária da região leste da América do Norte,[6] mas actualmente naturalizada em diversas regiões temperadas e subtropicais. Esta espécie é considerada o insecto xilófago economicamente mais importante nos Estados Unidos pelos danos que causa em estruturas construídas em madeira, sendo considerada uma praga com características infestantes.[6] A espécie alimenta-se de material celulósico, causando importantes danos em materiais como as estruturas em madeira de edifícios, materiais ornamentais, caixilharias e móveis em madeira, papel, livros e tecidos em algodão. Não são conhecidas subespécies.[4]
R. flavipes, à semelhança do que ocorre com outros insectos eusociaiss, partilham recursos e dividem tarefas com base num sistema de castas[6] de base fisiológica. Os indivíduos da espécie vivem em largas aglomerações, denominadas colónias, compostas de machos e fêmeas. Cada membro da colónia pertence a uma casta, a que corresponde um determinado padrão fisiológico, com as correspondentes características morfológicas associadas. Nesta espécie as castas são: (1) térmitas operárias; térmitas soldado; e a casta reprodutiva.[6]
Uma colónia madura pode conter entre 20 000 e 5 000 000 de operárias e a rainha da colónia põe entre 5 000 e 10 000 ovos por ano.[6]
Reticulitermes flavipes (Kollar, 1837) é uma espécie de térmita, do tipo subterrâneo da família Rhinotermitidae, originária da região leste da América do Norte, mas actualmente naturalizada em diversas regiões temperadas e subtropicais. Esta espécie é considerada o insecto xilófago economicamente mais importante nos Estados Unidos pelos danos que causa em estruturas construídas em madeira, sendo considerada uma praga com características infestantes. A espécie alimenta-se de material celulósico, causando importantes danos em materiais como as estruturas em madeira de edifícios, materiais ornamentais, caixilharias e móveis em madeira, papel, livros e tecidos em algodão. Não são conhecidas subespécies.