Reticulitermes flavipes, Eastern subterranean termites are the most common termites found in North America. This termite is the most economical and important wood destructive insect in the United States and is classified as a pest. They eat cellulosic materials such as structural wood in buildings, wooden furniture, paper, books, and cotton. Mature colonies can range from 20,000 workers to 5 million workers and the colony's main queen puts 5,000 to 10,000 eggs a day to increase this amount.
Video Eastern subterranean termite
Distribution
Eastern subterranean termites ( R. Flavipes ) are the most distributed species of Retisulitermes . It occurs throughout the eastern United States, including Texas, and can be found as far north as southern Ontario. In 2006, R. flavipes was also recorded in Oregon, on the west coast of the United States.
Reticulitermes santonensis in French is now understood as a synonym of R. flavipes . This species is now believed to originate in the southeastern United States and becomes exotic or invasive in southern Canada, Europe (France, Germany), South America (Uruguay, Chile), and the Bahamas. An unknown infestation of origin was also found in an Italian home in 2008. and a Korean house in 2017.
Maps Eastern subterranean termite
Description
Subterranean underground termites, like other social insects, share resources and divide labor based on a caste system. They live in a loose association society called colonies consisting of men and women. Termites in colonies are generally organized into worker caste, warrior caste, and reproduction caste.
Worker caste
Workers are about 3 mm long and blind, winged, soft-bodied, creamy white to grayish white with round heads. They are the majority of termites that actually eat wood. They are sterile and search for food and water, build and repair tube shelters, feed and care for other termites, care for eggs and young, and participate in colony defense.
Warrior caste
Army termites are also wingless and resemble workers, except that they have large, rectangular, yellowish brown heads with long black jaws. The main function of the army is the defense of colonies and mandibles primarily used to destroy ant enemies that may attack the colony. In addition, R. flavipes has a fontanelle (frontal gland) on the forehead that releases a mixture of terpenoid compounds. This secretion is synthesized de novo and is also used to maintain colonies of predators such as ants. The warrior caste accounts for only 1 to 2% of the entire colony. The soldiers can not afford to feed themselves and depend on the termites of workers to feed them spewed.
The reproductive caste
Immature termites on the sexual line, or reproduction, are called nymphs and can be distinguished from workers by the presence of wing buds. Under natural conditions, the work they do in the nest is negligible compared to that of the workers. They can feed themselves, but there is a debate about how long (more than how many instars) they retain this ability.
Alates (from Latin? L? Tus, "has wings") is a winged, sexually mature adult who is capable of spreading and crossbreeding. In R. flavipes , they are 8.5-10 mm long for their wingtips and have compound eyes, black oselus, and black to black cuticles completely sclerotized. As the species name (fl? V ?, "yellow" p? S, "foot"), the yellowish tarsi indicates. To distinguish R. flavipes from the same species (at least in the United States), the position of the octus may be used: to see the head from the side, the distance between the oselus and the closest compound at least by the diameter of the octus.
Alates always evolved from the nymph, with the last nymph stage marked by very long wing buds. After leaving the nest and swarming, the male and female allies, letting go of their wings, began digging new nests, and married. From this point onwards, they are called kings and queens, deeds, or primary reproductions.
Secondary reproduction, or neotenic, develops well from the reproductive line (neonatal brachypterous) or, in rare cases, the worker line (ergatoids). Ergatoids are the only members of the reproductive caste that have no wings or wings. Like workers, soldiers, and nymphs, they have no eyes. Ergatoids are rare in nature.
Brachypterous neotenics, which is common in the French population of R. flavipes, and probably other populations as well, evolved from the nymph through the pre-brachypterous neotenic stage such as nymph. They can be distinguished from the nymph by their short wing buds (brachy-, "short" -pterous, "have wings"), light brown pigmentation, slight sclerotization, and longer abdomens. As well, neotenik brachypterous also has compound eyes and oselus. Neotenic women lay eggs at a lower level than queens, but when present in large numbers, they can play an important role in the growth of the colony.
Life cycle
R. flavipes is opportunistic, and newly hatched termites can develop into one of a number of castes. At first, it becomes a worker termite and will most likely remain one for his entire age. Molting can turn a worker into a pre-army and then, a soldier. The warrior caste is the terminal stage which can no longer moult.
R. flavipes is also transformed into a nymph, which is a winged adult termite precursor called alates that is sexually mature. Termites Nymphal non terminal and can return to the worker stage. This back nymph is called pseudergat. Nymphs and workers can also develop into reproductive neoten secondary and tertiary respectively.
Behavior
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 restoration of the entire colony. R. flavipes work together in the care of children and also share their resources with nests.
Clustered is a dramatic and sudden appearance of R. flavipes alates in the afternoon from February to April. After this behavior, men and women lose their wings, in pairs, and form new colonies.
R. flavipes is a lifetime phone and there is no permanent central nest area. Therefore, all termite casts can be found in one of the different sites occupied by the colony. Their activity is determined by food, humidity and temperature, and movement is usually driven by one of these needs. Termites eat anything made of or contain cellulose, but can tunnel to non-cellulose-containing materials to gain access to their destination. This behavior can damage human activity.
Gut microbiota
Flagellates
Discovery
The first person to observe and formally portray the symbiotic flagellates at R. flavipes is the American paleontologist Joseph Leidy. In 1877, he reported his findings to the Philadelphia Academy of Natural Sciences, describing three new species he mistakenly perceives as parasitic celiats: Trichonympha agilis, Pyrsonympha vertens, and Dinenympha gracilis.
Prof. LEIDY commented that in searching for small animals under rock and wood chips in our forest, observing the very common Ants White, Termes flavipes, he noticed that the insect's gut, seen in the translucent stomach, became distended with brown matter. Feeling curious to learn the exact nature of the problem, he was surprised to find that it consisted mostly of infusion parasites and other parasites, mixed with small particles of rotting wood. In many instances, the parasites are so numerous that they form the largest part of most intestinal pulps. Every individual he examines, workers, soldiers, and winged forms, is full of parasites, estimated by millions.
Species in Reticulitermes flavipes
So far, at least 9 genera and 11 species of flagella symbiosis have been found at R. flavipes hindgut:
- Dinenympha fimbriata Kirby, 1924
- Dinenympha gracilis Leidy, 1877
- Holomastigotes elongatum Grassi, 1892
- Microjoenia fallax (Duboscq & GrassÃÆ' â € <â € <, ©, 1928)
- Monocercomonas sp. Grassi, 1879
- Pyrsonympha major Powell, 1928
- Pyrsonympha vertens Leidy, 1877
- Spironympha kofoidi Koidzumi, 1917
- Spirotrichonympha flagellata
- Trichomitus trypanoides (Duboscq & GrassÃÆ' â € <â € <Â ©, 1924)
- Trichonympha agilis Leidy, 1877
A 2003 study focusing on flagellon oxymonad found evidence of at least one additional undefined undefined Dinenympha . They also discover what they believe to be the "second" species Pyrsonympha that has not been described other than P. Vertens . The authors question whether the main P , first described in Reticulitermes hesperus, is actually found in R. flavipes and considers it a case of misidentification.
Role in digestion
Flagellata is a feature of all termite families except Termitidae, called "higher termites". They are found exclusively in the hindgut, especially the stomach, the enlarged part of the hindgut with an anaerobic interior that serves as a fermentor. In R. flavipes , the wood eaten by termites was first broken down by the mandible, treated with the parent endoglucanase from the salivary gland, milled into small particles in the gizzard, and then treated with additional host cellulase in midgut, liberating glucose. for immediate absorption. Then enter into the stomach, where the flagellata picks up particles of wood that are partially digested through endocytosis. Flagelates break down lignocellulose (xylan or cellulose) into simple sugars, fermented for their own energy needs, produce CO 2 , H 2 , and short-chain fat acids such as acetate as a product waste. Short chain fatty acids (also produced by homoacetogenic gut bacteria from CO 2 and H 2 ) can be directly absorbed by termite hosts. Much of the digestion occurs in the stomach: almost all xylanase activity, more than a quarter of endoglucanase activity, and nearly two thirds of exoglucanase activity in R. flavipes the digestive system is localized in hindgut and is associated with intestinal flagellata.
Although this is a obligat symbiosis, the newly hatched larvae do not have a bowel flagellata. This is obtained when larvae are given anal fluid containing flagellates from other colony members (trophallaxis proctodeal). Trophallaxis proctodeal is also used to fill flagellates and other intestinal symbionts after each moult.
Bacteria
Most bacterial species in termite colon are difficult or impossible to culture, so methods such as 16S RNA RNA ribosome are used to identify which groups are present. One such analysis of R. flavipes workers' wits found representatives of Endomicrobia (Elusimicrobia), Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, and Spirochaetes. The dominant bacterial hormone in core intestinal microbiomas is the genus Treponema (Spirochaetes), which accounts for about 32% of the sequences in other 16S rRNA studies. The same study identified Endomicrobia (Phylum: Elusimicrobia), which is the dominant endosymbionts of some protozoa in the thermotene gut. Arificial defects of species Reticulitermes by forcing meals on starch or starvation lead to the loss of flagellates and, by association, this endosymbiotic Endomicrobia, and an increase in the abundance of free living relatives. A rare free-living member of this class, the Endomicrobium proavitum , the first cultivated and named Endomicrobia species, was isolated from sterile intestinal homogenates filtered from defaunated (starch-fed) R. flavipes worker. It is believed to play a role in nitrogen fixation.
While some intestinal bacteria live freely in the intestinal lumen or attached to the intestinal wall, many others live in close connection with the flagellate. These include non-cultured Endomicrobia members (Elusimicrobia) and other taxa that live as cytoplasmic symbionts, as well as epibiotic symbionts attached to the outer surface of the cell. In R. flavipes , cytoplasmic symbionts have been identified in flagellates such as Trichonympha agilis (Hypermastigida) and Pyrsonympha vertens (Oxymonadida). The latter is also characterized by a symbiotic spirochaete epibiotic. In other termite species, the spirochaete Treponema genus member has been identified as endo and ellosymbionts flagellata: Similar associations may explain the dominance of Treponema in R. flavipes intestines.
Archaea
Archaea was isolated from R. flavipes hindgut including H 2 - and CO 2 -using methanogens Methanobrevibacter cuticularis and curvatus . Both species are believed to be the dominant methanogens in R. flavipes and are found in the microxic, peripheral regions of the hindgut, on or near the intestinal wall, where they are occasionally attached to the filament prokaryote.
Kaste specific differences
Although there is a nucleus microbiome divided between castes and colonies, alate castrate intestine is characterized by a much lower bacterial abundance in the genus Treponema (Spirochaetes) and Endomicrobia (Elusimicrobia) classes compared to workers and soldiers. Flagella in the Parabasalia class and the Oxymonadida order were also significantly less in the alate's intestine, with the latter significantly reduced as well.
Human impact
Along with Reticulitermes virginica , R. flavipes is responsible for 80% of the $ 2.2 billion spent annually in the United States on termite control. Termites eat wood cellulose, which means that their presence in man-made structures is often unnoticed for long periods of time. The infested termite wood will appear structurally from the outside, while inside it will have a honeycomb-like appearance. To detect the presence of R. flavipes observers can test the integrity of the wood by tapping it with a screwdriver. If any, R. flavipes is found at, near or below ground level. Trimming, sub-floor, floor, and structural woodwork are the most vulnerable to termite damage. Subterranean underground termite is considered a serious economic wood pest and it is estimated that in high activity areas more than 1 in 5 houses have or will be attacked.
Termite control methods include: physical barriers, chemical treatments, and physical treatments (such as heat, freezing, electrocution and microwave irradiation).
Structural damage to buildings instead of R. flavipes only affects humans. Termites also play an important role in the decomposition of organic matter in natural communities. Without termites, the accumulation of dead organic matter on the forest floor will undermine the integrity of the forest. The benefits provided by R. flavipes in terms of their contribution to environmental legislation may outweigh the harm they incur.
See also
- Wood Destroying Insect Report
References
External links
- Subterranean Termite Biology in Eastern States - Ohioline 1209 Bulletin, Ohio State University
- Subterranean Termite Factsheet from the National Pest Management Association with information on habit, habitat and prevention
- East Subterranean Sub-East Fact Sheet - Penn State Entomology Department
- Termites & amp; Pest Control - Fumapest Termites & amp; Pest Control
Source of the article : Wikipedia
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