28 species of organisms prey upon alfalfa leafcutting bees or destroy their nests. Their primary predators are checkered flower beetles, which invade nest cells and feed on larvae.
Known Predators:
Alfalfa leafcutting bees are the smallest leafcutting bees, ranging in size from 60 to 190 mm. They are dark gray in color and demonstrate sexual dimorphism. Females have a white scopa, elongated hairs for carrying pollen, on the underside of the abdomen, and shorter white hairs on the rest of their body. Males tend to have a pair of creamy white to yellow spots near the end of the abdomen
Range length: 60 to 190 mm.
Sexual Dimorphism: sexes colored or patterned differently
Other Physical Features: ectothermic ; bilateral symmetry
In captivity, female alfalfa leafcutting bees usually live 1 to 2 months, and males live 3 to 4 weeks. Lifespan is affected by weather, environmental conditions, and how well parasites are controlled. Lifespan is shorter in the wild due to uncontrolled environments; females generally live 3 to 5 weeks and males 1 to 3 weeks.
Range lifespan
Status: wild: 7 to 35 days.
Range lifespan
Status: captivity: <1 to 2 months.
Average lifespan
Status: captivity: 1 months.
Typical lifespan
Status: wild: 7 to 28 days.
Average lifespan
Status: wild: 14 days.
Typical lifespan
Status: captivity: 1 to 2 months.
Average lifespan
Status: captivity: 1 months.
Alfalfa leafcutting bees nest in a variety of locations such as rotting wood, flower stems, soda straws, and other spaces that allow for the construction of tubular nests. They also adapt well to man-made structures.
After selecting and preparing a nest site, alfalfa leafcutting bees seek out leaves to make individual nesting cells within the nest. They often use leaves of Virginia creeper (Parthenocissus quinquefolia) and green ash (Fraxinus pennsylvanica). Alfalfa leafcutting bees cut distinct circles about 2.5 cm in diameter in these leaves, which are used to create nest cells. Nests may contain up to 2 dozen cells and measure 18 cm in length.
Habitat Regions: temperate ; terrestrial
Other Habitat Features: urban ; suburban
Alfalfa leafcutting bees, Megachile rotundata, are native to southwestern Asia and southeastern Europe. There were introduced to North American in the 1930's and more recently to Australia to increase pollination of Alfalfa crops.
Biogeographic Regions: nearctic (Introduced ); palearctic (Native ); oriental (Native ); australian (Introduced )
Leafcutting bees in the genus Megachile are typically polylectic, gathering food from many different plants. Alfalfa leafcutting bees, as their common name suggests, prefer alfalfa (Medicago sativa). Adults eat both nectar and pollen. Nectar is obtained by prying open the keel of plants and inserting their proboscis. Pollen is transported on the underside of the abdomen in pollen carrying brush, or scopa. Most other bees are unable to pry open the flower of alfalfa.
Plant Foods: nectar; pollen
Primary Diet: herbivore (Nectarivore )
Alfalfa leafcutting bees are important pollinators, especially of the plant alfalfa (Medicago sativa). They are preyed upon by 28 different species and act as host to 8 species of parasites. Parisitoids of the genera Pteromalus, Monodontomerus, Tetrastichus and Melittobia emerge before bees and parasitize bees as they develop. Alfalfa leafcutting bees are also vulnerable to a chalkbrood disease (Ascosphaera aggregate Skou), which is caused by a fungus. This fungus invades nest cells of developing larvae and infects them, causing larvae to harden, take on the consistency of chalk, and turn either white, black, or gray. Infected larvae die before reaching maturity. This disease is spreading rapidly and could ultimately affect crops of alfalfa as numbers of pollinators decrease.
Ecosystem Impact: pollinates
Commensal/Parasitic Species:
Because they are such effective pollinators of alfalfa (Medicago sativa), alfalfa leafcutter bees were introduced to North America in the 1930's to aid alfalfa crop production. Crop production is said to have increased by nearly 60% in some areas of North America.
Positive Impacts: pollinates crops
Although alfalfa leafcutting bees cause some leaf and flower damage to ornamental plants, the effect is minimal. They also sting humans when handled, though the sting is considered half as painful as that of a honeybee.
Negative Impacts: injures humans (bites or stings); household pest
Alfalfa leafcutting bees undergo complete metamorphosis, and have 4 larval instars. After hatching from eggs in early winter, larvae grow and develop until spring. They overwinter as mature larvae. As temperatures reach 24 to 30 ˚C in the Spring, larvae develop into pupae over the following 3 to 5 weeks. As larvae and pupae, they feed on provisions which were wrapped inside the nest cell by their mother. After 18 to 20 days, adult males begin to chew their way out of the cell. Females exit the cell after 21 to 24 days.
Development - Life Cycle: metamorphosis
Alfalfa leafcutting bees are not currently considered threatened. In California, however, a recently introduced species of bee, Megachile apicalis, may compete with alfalfa leafcutting bees for nesting material.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
Alfalfa leafcutting bees, like most bees, can perceive ultra-violet light as well as most colors visible to humans. They are able to return to nesting sites as well as favored foraging areas. When in captivity, they place their nests near knotholes, edges, or other markers. Little is know regarding communication between alfalfa leafcutting bees.
Perception Channels: visual ; ultraviolet; tactile
After adult female alfalfa leafcutting bees emerge from nest cells, they immediately start to mate. A male lands on a female and lifts her abdomen with his legs. If the female accepts the invitation, she withdraws her singer and unites her genitals with those of the male. Mating lasts between 30 and 45 seconds. Alfalfa leafcutting bees are polygynous.
Mating System: polygynous ; cooperative breeder
Female alfalfa leafcutting bees breed immediately after exiting the cell. Breeding occurs once a year, usually during June and July. Shortly after mating, female alfalfa leafcutting bees lay their eggs inside nest cells. Females lay between 18 and 40 eggs over a period of 2 weeks (average less than 25 eggs). Most eggs are fertilized, although unfertilized eggs are generally born as males. Some seasons yield fewer males than other seasons.
Breeding interval: Alfalfa leafcutting bees breed once per year.
Breeding season: Breeding of alfalfa leafcutting bees usually occurs between June and July.
Range eggs per season: 18 to 40.
Average eggs per season: <25.
Range gestation period: 1 to 2 1/2 weeks.
Average gestation period: 2 weeks.
Key Reproductive Features: seasonal breeding ; sexual ; fertilization (Internal ); oviparous
Female alfalfa leafcutting bees prepare a nest and nest cells for their offspring. They provide nest cells with nectar and pollen to provision offspring. Before laying her eggs, a female thoroughly cleans her abdomen with her legs to ensure eggs are clean. Eggs are laid in nest cells over a period of 2 weeks. After this time, females die, and offspring develop without further parental care.
Parental Investment: female parental care ; pre-fertilization (Provisioning); pre-hatching/birth (Provisioning: Female, Protecting: Female); inherits maternal/paternal territory
Megachile rotundata és una abella europea que ha estat introduïda en diverses regions del món. Com a espècie d'abella solitària, no construeix colònies ni emmagatzema mel, però és una pol·linitzadora molt eficaç d'alfals, vegetals i algunes fruites, fet pel qual els agricultors l'acostumen a utilitzar com a ajuda per a la pol·linització dels seus cultius.[1][2] Les femelles construeixen i proveeixen el seu propi niu en arbres vells o forats dels troncs[3] i els folren amb fulles tallades.[4] Aquestes abelles s'alimenten de pol·len i nèctar i presenten dimorfisme sexual. Se sap que aquesta espècie mossega i pica però no representa perill a menys que se senti amenaçada o danyada, i la seva picada ha estat descrita com la meitat de dolorosa que la d'una abella de la mel.[5]
Megachile rotundata és una abella europea que ha estat introduïda en diverses regions del món. Com a espècie d'abella solitària, no construeix colònies ni emmagatzema mel, però és una pol·linitzadora molt eficaç d'alfals, vegetals i algunes fruites, fet pel qual els agricultors l'acostumen a utilitzar com a ajuda per a la pol·linització dels seus cultius. Les femelles construeixen i proveeixen el seu propi niu en arbres vells o forats dels troncs i els folren amb fulles tallades. Aquestes abelles s'alimenten de pol·len i nèctar i presenten dimorfisme sexual. Se sap que aquesta espècie mossega i pica però no representa perill a menys que se senti amenaçada o danyada, i la seva picada ha estat descrita com la meitat de dolorosa que la d'una abella de la mel.
Die Luzerne-Blattschneiderbiene (Megachile rotundata) ist eine Art aus der Gattung Megachile (Blattschneider- und Mörtelbienen) aus der Ordnung der Hautflügler. Sie ist die weltweit am intensivsten wirtschaftlich genutzte Solitärbiene.
Die Weibchen der Luzerne-Blattschneiderbiene erreichen 8 bis 10 mm, die Männchen 6 bis 8 mm Körperlänge. Die Geschlechter sind unterschiedlich gefärbt. Die Körperfarbe des Weibchens ist schwarz, wird aber durch unterschiedlich starke Behaarung auf verschiedenen Körperteilen überdeckt. An den Enden der Rückenplatten des Hinterleibs befinden sich gelbe Haarbinden. Der Hinterleib ist abgeflacht und zum Körperende zugespitzt. Als Bauchsammler besitzt die Luzerne-Blattschneiderbiene auf der Bauchseite mehrere parallele Reihen weißer Borstenhaare, die als Sammelbürste zum Aufnehmen des Pollens dienen.
Während Kopf und Brust bei den Weibchen wenig behaart sind, lässt die stärkere Behaarung die Männchen grauschwarz erscheinen. An Stirn und Kopfschild der Männchen befinden sich dichte gelbbraune Haare. Die vorderen Bauchplatten des Hinterleibs besitzen weiße Fransensäume. Das stumpfe Körperende trägt zwei helle Haarpunkte.
Die Facettenaugen der weiblichen Tiere sind schwarz, die der männlichen grün.
Das ursprüngliche Verbreitungsgebiet erstreckt sich von Nordafrika über den Mittelmeerraum bis nach Südfinnland und nach Mittelasien. In Mitteleuropa tritt die Luzerne-Blattschneiderbiene inselartig auf, dabei bevorzugt sie trockenwarme Standorte, wie südgerichtete Trockenhänge und Sandflächen.
Auf nicht bekanntem Weg kam die Luzerne-Blattschneiderbiene in der Mitte der 1930er Jahre nach Nordamerika, wo sie erstmals 1937 in Virginia nachgewiesen wurden. Sie breitete sich kontinuierlich nach Westen aus und erreichte 1954 Kalifornien und 1958 Oregon. Dabei wurde sie in einigen Regionen, insbesondere im Nordwesten der USA, wo auf einem relativ hohen Anteil der landwirtschaftlichen Nutzfläche Luzerne-Saatgut produziert wurde, die dominierende Blattschneiderbienenart.
Die Luzerne-Blattschneiderbiene lebt wie die anderen Blattschneiderbienenarten solitär. Die Flugzeit der Weibchen beginnt in Mitteleuropa selten vor Ende Mai und endet meist im August. Nach dem Schlüpfen der ausgewachsenen Tiere erfolgt zunächst die Paarung, bevor mit der Nisttätigkeit begonnen wird. Als Nistplatz nutzt die Luzerne-Blattschneiderbiene hohle Pflanzenstängel, Schilfrohrdächer und Fraß- bzw. Bohrgänge im Holz, seltener Lehmwände oder den Erdboden. In die Niströhren werden ovale Ausschnitte geeigneter Laubblätter eingetragen, wie etwa der Luzerne, seltener von Rosen oder Sonnenblumen. Daraus baut das Weibchen fingerhutartige Zellen, die zu etwa zwei Dritteln mit einem teigartigen Gemisch aus Pollen und Nektar gefüllt werden. Das restliche Drittel wird allein mit Nektar gefüllt, auf den das Ei abgelegt wird. Danach wird die Zelle mit mehreren kreisrunden Blattausschnitten verschlossen. In einer Niströhre werden hintereinander mehrere Brutzellen angelegt. Mit einem Pfropfen aus Blättern wird die Röhre verschlossen.
Aus dem Ei entwickelt sich nach zwei bis vier Tagen die Larve, die sich vom eingetragenen Pollen-Nektar-Gemisch ernährt. Sie häutet sich innerhalb von zehn Tagen viermal. Der Enddarm bleibt bis zum Alter von etwa drei Wochen verschlossen, wodurch eine Verunreinigung der Nahrung vermieden wird. Erst dann legt die Larve einen Ring von Exkrementkügelchen an der Innenseite des Zelldeckels ab. Danach spinnt sie sich in einen seidig glänzenden Kokon ein, in dem sie als voll ausgewachsene Ruhelarve oder Präpuppe überwintert. Erst im folgenden Frühjahr entwickelt sie sich zur Puppe und danach zur voll ausgewachsenen Biene.
In den 1950er Jahren kam es in den USA und Kanada zu einem deutlichen Rückgang der Erträge in der Luzernesaatgutproduktion. Die Dezimierung der nordamerikanischen Bienenfauna wurde als Hauptursache dafür angesehen. Es wurden Untersuchungen an verschiedenen Luzerne bestäubenden Insekten durchgeführt, um darunter für eine mögliche kontrollierte Aufzucht geeignete Arten zu finden. Nachdem erste Versuche mit einer 1958 zufällig gefundenen größeren Population der Luzerne-Blattschneiderbiene erfolgreich angelaufen waren, wurde gezielt nach geeigneten Haltungsmöglichkeiten gesucht. Bis 1970 wurden in den Gebieten mit Luzernesaatgutproduktion der USA und dem südlichen Kanada Bienen angesiedelt, die durch bereitgestellte Niströhren von den Farmern meist selbst gefangen wurden. Dabei kam es zu Problemen durch Parasitenbefall, infolgedessen Haltung und Einsatz der Bienen vor allem durch Spezialisten vorgenommen wurden. Einige Farmen stellten sich komplett auf die Vermehrung der Luzerne-Blattschneiderbiene um. Zwischen 1975 und 1985 wurden jährlich ungefähr 750 Millionen Brutzellen gehandelt, deren Stückpreis zu dieser Zeit bei 1,5 bis 2,5 Cent lag. Daneben entwickelte sich ein Markt mit Zubehör für Zucht und Haltung dieser Solitärbienen.
Die Erträge an Luzernesaatgut konnten mit Hilfe der Luzerne-Blattschneiderbiene deutlich gesteigert werden. So lag der Ertrag im Staat Washington ohne diese Art in den 1960er Jahren bei 100 bis 350 Kilogramm pro Hektar, während mit den Bienen Spitzenwerte von bis zu 2200 Kilogramm pro Hektar erzielt wurden. In Neuseeland, wo nur zwei von vierzig einheimischen Bienenarten Luzernebestäuber waren, stiegen die Erträge von 75 auf 300 bis 750 Kilogramm pro Hektar.
Durch Bereitstellung geeigneter Niströhren wird die Ansammlung der Bienen im Umfeld der zu bestäubenden Felder unterstützt. Neben Holzstücken mit Bohrungen von fünf bis sechs Millimeter Durchmesser und Papierröhren bewährten sich vor allem etwa ein Zentimeter starke Holzbretter mit auf beiden Seiten eingefrästen halbkreisförmigen Rillen, die durch Aufeinanderlegen zu beliebig großen Nistblöcken zusammengesetzt werden. Bei der kontrollierten Haltung werden die Brutzellen nach Ende des Bestäubungseinsatzes aus dem Nistmaterial entnommen, unfertige oder mit Parasiten befallene aussortiert und in verschließbaren Behältern kühl gelagert. In Bruträumen oder Inkubatoren wird der Schlupftermin durch Regulierung von Temperatur und Luftfeuchtigkeit genau gesteuert und der Luzerneblüte angepasst. Bei Schlupfbeginn werden die Bienen in den Brutbehältern aufs Feld gebracht.
Im Freiland wird mit Besatzstärken zwischen 5.000 und 50.000 Brutzellen pro Hektar gearbeitet. Bei Einsatz in Gewächshäusern sind deutlich weniger Tiere erforderlich und es kann auf die bei Hummeln und Honigbienen erforderliche Zusatzfütterung verzichtet werden. Stattdessen müssen geeignete Blattquellen für den Bau der Brutzellen zur Verfügung gestellt und Beleuchtungsstärken von mindestens 5.000 Lux gewährleistet werden. Durch die Möglichkeit, den Schlupftermin gezielt steuern zu können, steht die Luzerne-Blattschneiderbiene ganzjährig als Bestäuber zur Verfügung.
Durch die vom Menschen geförderte, annähernd weltweite Verbreitung der Luzerne-Blattschneiderbiene ist das Spektrum der Parasiten regional unterschiedlich. Zahlreiche Arten von Parasiten nutzten zuvor andere Wildbienenarten als Wirte. So waren 1961 im Nordwesten der USA keine natürlichen Feinde der Luzerne-Blattschneiderbiene bekannt, 1967 waren es 30 Arten. Bedeutende Brutparasiten sind in Nordamerika die Erzwespen Monodontomerus obscurus (Westwood), Tetrastichus megachilidis (Burks), Melittobia chalybii (Ashmead), Pteromalus venustus (Walker) und Dibrachys maculipennis (Szelenyi) sowie die Keulenwespe Sapyga pumila (Cresson). In Europa parasitieren vor allem Buntkäfer der Gattung Trichodes, Kegelbienen und die Erzwespe Melittobia acasta (Walker). Verschiedene Schwarzkäfer und der Speckkäfer Trogoderma glabrum (Herbst) treten als Nahrungsräuber auf.
Die Luzerne-Blattschneiderbiene (Megachile rotundata) ist eine Art aus der Gattung Megachile (Blattschneider- und Mörtelbienen) aus der Ordnung der Hautflügler. Sie ist die weltweit am intensivsten wirtschaftlich genutzte Solitärbiene.
Megachile rotundata, the alfalfa leafcutting bee,[1] is a European bee that has been introduced to various regions around the world. As a solitary bee species, it does not build colonies or store honey, but is a very efficient pollinator of alfalfa, carrots, other vegetables, and some fruits. Because of this, farmers often use M. rotundata as a pollination aid by distributing M. rotundata prepupae around their crops.[2] Each female constructs and provisions her own nest, which is built in old trees or log tunnels.[3] Being a leafcutter bee, these nests are lined with cut leaves.[4] These bees feed on pollen and nectar and display sexual dimorphism. This species has been known to bite and sting, but it poses no overall danger unless it is threatened or harmed, and its sting has been described as half as painful as a honey bee's.[5]
M. rotundata is a member of the subfamily Megachilinae, which includes more than 4,000 bee species; this currently makes this family the second-largest among all bee families. This subfamily is one of four other subfamilies of Megachilidae, the other three being the Fideliinae, Pararhophitinae, and Lithurginae. Phylogenetic studies suggest that this subfamily is monophyletic.[6] More specifically, it belongs to the genus Megachile, which contains 52 subgenera and 1,478 species. The genus Megachile consists of bees that cut leaf pieces to line their nests.[5]
M. rotundata is a European leaf-cutting bee placed in the subgenus Eutricharia, the "small leaf-cutting bees"; they are 6–9 mm (0.24–0.35 in) in length.[7][8] They are partially bivoltine, meaning that under the right conditions they can produce two generations per year.[9] These bees present a sexual dimorphism, in which the males are smaller than the females and differently marked.[10] M. rotundata bees are a dark grey color. Females have white hairs all over their bodies, including on their scopae. In contrast, males have white and yellow spots on their abdomens.[5]
M. rotundata is currently found on all continents except Antarctica.[6] In North America, the species was deliberately imported to assist in the pollination of food crops, but has now become feral and widespread.[11] In New Zealand and Australia, M. rotundata was also introduced to assist in the pollination of alfalfa (known locally as lucerne), in 1971 in New Zealand,[12][13] and 1987 in Australia.[14][15]
Females construct tubular nests in a variety of sites, including rotting wood, flower stems, reeds, and soda straws. In the wild, females also create nests in small holes in the ground or in available cracks/crevices in trees or buildings. The nests are composed of a string of individual cells, as many as the space will allow. When managed for pollination, the females are induced to nest in paper cylinders similar to drinking straws or drilled blocks of wood.
Each cell is made from circular disks cut from plant leaves using the bee's mandibles, hence the name "leafcutter".[11] Females use about 15 leaves per cell, called a concave bottom, overlapping the leaves to produce the thimble-shaped cell.[3] While the bees do not store honey, females do collect pollen and nectar which they store in the cells of their nests.[11] Specifically, females first regurgitate the nectar they have provisioned into the cell and then transfer the pollen that is attached to their scopa on top of the nectar.[3] Each cell contains one pollen and nectar ball, and one egg[11] with each cell containing a 2:1 nectar-to-pollen ratio.[3] The completion of one cell in the nest requires between 15 and 20 provisioning trips. After the female lays her eggs, she seals the cell with circular leaf pieces.[3]
Studies reveal that positioning of male and female progeny in the nest is strategic and that cell size plays a major role in the size of progeny, independent of the mother's size. Females have been observed to lay female eggs in the inner cells and male eggs in the outer cells. With respect to sex ratios, larger cell provisions are correlated with a greater production of female offspring. Two explanations exist for these behaviors in terms of mother's foraging behaviors: 1) The mother brings more provisions to the inner cells because she expects that female progeny will be produced there and 2) the mother chooses to fertilize her egg, and therefore promotes the production of female progeny, because she has to bring larger provision proportions to a larger cell.[16] The sex ratio changes depending on nest size, length, and nesting material. This ratio is controlled by the female. These observations have been made for females that make their nests in tunnels. For example, a 5.5 mm tunnel, diameter is associated with a 3:1 ratio and a 6.0 mm tunnel diameter is associated with a 2:1 ratio of males to females. Shorter tunnels, those that are below 5.0 cm long, are less favorable.[17]
During nest construction, females transfer olfactory cues onto their nests to facilitate nest recognition. Specifically, they transfer these hormones by running their abdomens along the nest or excreting liquid from the tip of the abdomen. The olfactory cues are especially concentrated around the nest entrance. When these olfactory cues were experimentally removed, females of M. rotundata were unable to identify their own nests, revealing the importance of these chemicals. The chemical composition of these olfactory cues includes hydrocarbons, wax esters, fatty aldehydes, and fatty alcohol acetate esters.[18]
As a member of the Hymenoptera order, this bee is haplodiploid.[19] Adults emerge by the end of the summer through one of two developmental pathways: larvae will develop by the end of one summer and proceed through the a prepupal diapause phase until the next summer, or larvae, known as "second-generation" bees, skip this phase and emerge as adults in the same summer.[9]
The larva transitions through four instar stages before emerging as an adult. During its development, which occurs rapidly, the larva consumes the pollen ball and enters diapause when the pollen is fully consumed. In its progression into the diapause phase, the larva defecates pellets in a ring formation and then spins its cocoon out of silk threads. The next spring, the mature larva pupates, a process that lasts 3–4 weeks, and completes its development. Once the bee is developed, it cuts its way out from the nest by chewing itself out of its cocoon.[3]
Upon emergence, females mate immediately and begin constructing their nests after a week.[4]
Progeny released via the two alternative pathways for emergence display different sex ratios and sizes. Among adults that emerge during the summer of the same year, the sex ratio is biased towards males. Among the "second-generation bees", however, the sex ratio is female biased. Further, spring-emergent adults weigh more than summer-emergent ("second-generation") adults. These differences have been proposed to be attributed to the chances of survival to mating of the two sexes and the metabolic costs involved in development. Bees that undergo diapause and emerge in the spring must endure the long winter, so require more food stores. As a result, they will be larger when they mature. Another explanation has been that smaller bees mature faster, thus are able to mate more quickly when they emerge in the summer to avoid the cold, harsh conditions of the winter.[20]
The sex ratio of the offspring also depends on the distance between nesting and foraging sites. Females have been observed and determined to bias their offspring sex ratio to males at larger flight distances from the nest.[10]
Research on second-generation bees illustrates that kin recognition of nest mates is not a genetically based behavior. Further, fratricide has been hypothesized to be a nondiscriminatory behavior; emerging individuals treat developing siblings and nonsiblings similarly. When developing in cells behind diapausing bees, inner-nesting bees either bypass the nest in front of them, retreat back to their nests until diapausing individuals emerge, or chew through the nesting cells in front of them, killing the diapausing bees. These decisions are contingent on the extent of development of delay of nestmates. For example, emerging individuals would remain in their cells when they were delayed from emerging for a relatively short period of time. When delayed for longer periods of times, however, emerging individuals would use their mandibles to destroy the cells of their nest mates. With respect to gender differences, males have been observed to bypass nests more frequently than females due to the small size of males.[21]
M. rotundata has been found to be a monandrous bee species.[22] During the mating season, males attempt to obtain mates by positioning themselves at sites where female are likely to be, including foraging sites and nests. While females can mate several times, they resist male advances by restricting their mating to one sexual interaction and fleeing from these males. This behavior is attributed to female productivity during the construction of her nest and egg-laying. When harassed, females are unable to build their nests efficiently, making less foraging trips and spending a longer time overall in nest construction. Fleeing allows females to avoid being mounted. In the process of fleeing, however, females may lose their nesting materials, such as leaves and must then make an additional trip to make up for the lost materials.[19]
Sexual pheromones in epicuticular waxes are released by females to assist in attracting males as mates. Studies of the emissions from these waxes reveal that alkenes are the primary compound detected by males. Further, females of different ages emit different pheromones, containing different alkene compositions. In young females, substances that classify as either 7-pentacosene or 9-pentacosene are present in the highest concentrations and, in older females, 5-monoene compounds predominate. During mating season, males are able to detect these pheromones and preferentially select young females to copulate with.[23]
M. rotundata can feed on nectar and pollen from a variety of plants[24] but prefer Medicago sativa.[5] Females will immediately begin feeding after emergence during the maturation period of their eggs.[4] During feeding, the bee will insert its proboscis into the keel of the plant. In the process, pollen is brushed onto its scopa.[5]
Currently, 28 species are known to prey on M. rotundata, all of which have unique ways of invading and destroying their host nests. Some species include Trogoderma glabrum, Trogoderma variabile, Tribolium audax, Tribolium brevicornis, and Trichodes ornatus. T. ornatus is the most formidable predator, with females laying their eggs in cracks between leaf pieces. During development, T. ornatus larvae kill host bee larvae and consume pollen from nest provisions. When it reaches the third stage of development, it burrows into adjacent cells and consumes host larvae irrespective of host larval instar stage. In another case, female T. glabrum females lay eggs in cracks between cells at the back of the nest. As they develop, the larvae begin to consume host larvae, moving towards the front of the nest and eating females first. In a third case, T. variabile attacks M. rotundata when it is in its cocoon or the pupal stage.[25]
Various families of wasps are the primary parasites of M. rotundata. Some species include Pteromalus venustus, Monodontomerus obscurus, Melittobia chalybii, Diachys confusus,[3] and Sapyga pumila.[4] The most formidable predator of this species is P. venustus, a parasitoid wasp in which the female uses her ovipositor to sting a developing M. rotundata larvae or pupae.[3] After stinging to paralyze its host, the female lays her eggs on the host's surface and the development of the parasite offspring takes place. After about 15–20 weeks, adults of P. venustus emerge.[3]
Other parasites include several species of Coelioxys and Nemognatha lutea. Coelioxys spp. take advantage of instances when females of M. rotundata are away from the nest, such as during foraging, to lay their egg in the host nest cells. Once a Coelioxys reaches the larval stage, it will kill the developing, host larva and consume all of the provisions that the host female placed in the nest. N. lutea, in contrast, initiate parasitism of hosts at foraging sites. Specifically, female N. lutea will lay their eggs on flowers and, when a bee arrives at this flower during provisioning, will secure itself, as a triungulin stage, to the bee. The triungulin will then, upon the host bee's arrival to its nest, remove itself from the bee, entering a cell and consuming all the provisions gathered by the host female.[3]
Males of the species may, presumably by mistake, attempt to mate with other bee species that are using the same foraging areas as female leaf cutters. They follow several inches behind their intended partner, whether a leaf cutter or bumble bee, which is moving around a plant seeking a flower; then when the target does alight, the male leaf cutter darts rapidly onto the target's back. This causes bumble bees and nonreceptive female leaf cutters to move to another flower and in the process shed the male leaf cutter. The male may then move right to the next prospect, or may first stop for a sip of nectar.
Chalkbrood disease in M. rotundata, specifically larvae, was discovered in 1974 in Nevada. This disease occurs from exposure of M. rotundata to Ascosphaera aggregata, which is introduced into the nest cells through nectar and pollen provisions that females bring back from foraging visits.[26] Signs of chalkbrood infection have been observed to occur in the fifth-instar larvae, leading to the milky appearance of the larval hemolymph and development of a pink, tan, or gray cast in their head or abdominal regions. These changes are accompanied by the spread of pink, tan, or gray color throughout the body of the larvae, and dark-colored, fungal cysts appear under the cuticle.[27]
A variety of microorganisms have been isolated from the alimentary canals and frass of M. rotundata. Bacteria include Bacillus firmus, B. licheniformis, B. megaterium, B. pumilus, and Streptomyces spp., and fungi include Trichosporonoides megachiliensis.[10] With respect to the development of chalkbrood, the bacteria and fungi may promote the inhabitation of A. aggregata. This is supported by observations in chalkbrood-diseased larvae, which contain higher levels of bacteria and fungi in their guts than in healthy larvae.[26]
In controlling chalkbrood, such methods as decontamination of nest cells and materials and shelters was initially achieved using household bleach. Current methods include paraformaldehyde fumigation.[3]
Female alfalfa leafcutter bees have stingers, but both sexes usually use their mandibles as a defensive mechanism, usually only defending themselves when squeezed or antagonized. So, bee suits, such as those required with honey bees, are not necessary when dealing with these bees. When these bees do sting, however, they do not lose their stingers or die after stinging.[5]
In managing M. rotundata for pollination, such methods as dichlorvos pest strips and ultraviolet lamps placed above liquid traps are effective in killing parasitoids, but not harming M. rotundata.[4] Other methods of preventing parasitoid invasion include physical barriers. For example, the presence of thick artificial cavities separating the exterior from the nest and application of a felt cloth sealing to the back of the nesting board prevents parasitoid access to the nest.[3] Another way that pest are controlled is by opening up the nesting material and cleaning the cocoons.[28]
M. rotundata was accidentally introduced into the United States during the 1940s, and its management as a pollinator leads to increases in seed production of some crops in the U.S. It has been shown to pollinate these plant species:[4]
Such behaviors as gregarious nesting, use of leaves and nesting materials that have been mass-produced by humans, efficient pollination of M. sativa, and synchronous emergence of adult bees during alfalfa blooming period provide positive benefits for the use of these bees in agricultural development.
When these bees are supplied to farmers for pollinating crops, they are usually supplied in a dormant state called prepupal, and kept in such state by a constant temperature of about 7 °C (45 °F). At a time that is appropriate for the crop's flowers, the farmer puts the prepupal form in an incubating environment, a constant temperature around 27 °C (81 °F) The adult bees emerge from the pupal form after about 25 days at that temperature. Then, the farmer brings the bees to the field.[2][29]
Megachile rotundata, the alfalfa leafcutting bee, is a European bee that has been introduced to various regions around the world. As a solitary bee species, it does not build colonies or store honey, but is a very efficient pollinator of alfalfa, carrots, other vegetables, and some fruits. Because of this, farmers often use M. rotundata as a pollination aid by distributing M. rotundata prepupae around their crops. Each female constructs and provisions her own nest, which is built in old trees or log tunnels. Being a leafcutter bee, these nests are lined with cut leaves. These bees feed on pollen and nectar and display sexual dimorphism. This species has been known to bite and sting, but it poses no overall danger unless it is threatened or harmed, and its sting has been described as half as painful as a honey bee's.
Megachile rotundata o abeja cortadora de hojas de la alfalfa es una especie europea que ha sido introducida en otras regiones del mundo.[1] Es una especie solitaria, es decir que no construye colonias, sino que cada abeja construye su propio nido y cuida sus crías independientemente. Los nidos se pueden encontrar en árboles viejos o troncos.[2] El interior de los nidos está forrado de trozos de hojas.[2]
Es un eficiente polinizador de la alfalfa, como así también de algunas verduras (zanahorias) y frutas. Por esta razón los agricultores a menudo usan M. rotundata para la polinización de cosechas.[2]
Megachile rotundata o abeja cortadora de hojas de la alfalfa es una especie europea que ha sido introducida en otras regiones del mundo. Es una especie solitaria, es decir que no construye colonias, sino que cada abeja construye su propio nido y cuida sus crías independientemente. Los nidos se pueden encontrar en árboles viejos o troncos. El interior de los nidos está forrado de trozos de hojas.
Es un eficiente polinizador de la alfalfa, como así también de algunas verduras (zanahorias) y frutas. Por esta razón los agricultores a menudo usan M. rotundata para la polinización de cosechas.
Megachile rotundata on Euroopas elav lehemesilane, kes on hea tolmeldajana introdutseeritud muu hulgas Põhja-Ameerikasse, Austraaliasse ja Uus-Meremaale.
Üksikult elava mesilasena ei ehita ta kolooniaid ega kogu mett, kuid on väga kasulik tolmeldaja lutsernile, porgandile ja paljudele teistele taimeliikidele.
Megachile rotundata on Euroopas elav lehemesilane, kes on hea tolmeldajana introdutseeritud muu hulgas Põhja-Ameerikasse, Austraaliasse ja Uus-Meremaale.
Üksikult elava mesilasena ei ehita ta kolooniaid ega kogu mett, kuid on väga kasulik tolmeldaja lutsernile, porgandile ja paljudele teistele taimeliikidele.
L'abeille découpeuse (Megachile rotundata) ou abeille tapissière[1], est une espèce d'abeilles solitaires appartenant au genre Megachile. Ces abeilles construisent des loges à partir de morceaux de feuilles découpées de (luzernes, troènes, acacias...), dans lesquelles elles déposent leurs œufs.
Une de ses particularités est de découper avec une méthode spectaculaire des morceaux de feuilles tendres (découpe circulaire à ovale aux bords nets, toujours en bordure de feuille ou de foliole) qu'elle transporte ensuite en vol afin de fabriquer son nid constitué de logettes confectionnées à partir des morceaux de feuilles enroulées (aspect de petits cigares).
Un nombre important de feuilles peuvent ainsi être découpées, sur le robinier faux-acacia par exemple (photo ci-contre), sans conséquence apparente pour le végétal (la « cicatrisation » se fait rapidement, notamment grâce au fait que l'abeille ne coupe pas les nervures importantes).
Elle fait partie d'un groupe de mégachiles assez petites (5-20 mm). Elle a une brosse ventrale blanche (Megachile pilidens qui lui ressemble a une brosse partiellement noire à l'arrière et présente deux taches feutrées blanches sur le 6e tergite). En tant qu'espèce solitaire, elle ne construit pas de ruche et ne forme pas de réserve de miel, mais elle est considérée comme un pollinisateur très efficace notamment de la luzerne, des carottes, et de nombreuses légumineuses cultivées, ou de plantes à baies (myrtilles[2]). Des nids artificiels positionnés près des cultures (nids à base de pailles, ou constitués de blocs de bois percés de trous d'un diamètre convenant à l'espèce) augmentent significativement les rendements de certaines cultures[3].
L'espèce est caractérisée par des mandibules surdéveloppées et très coupantes, utilisées pour découper les feuilles qu'elle recherche pour confectionner son nid, mais aussi comme mécanisme de défense quand elle se sent attaquée.
Sex-ratio : il est généralement de un mâle pour une femelle, soit très différent de ce qui se produit chez les abeilles coloniales.
Reproduction : dans la nature, les femelles construisent de petits nids dans des anfractuosités du sol, de parois rocheuses ou de murs, ou dans les arbres. Elles utilisent volontiers des nichoirs artificiels (des trous percés dans un bout de bois ou des tiges creuses : bambou, carton, paille, roseaux). Chaque nid est constitué d'une série de cellules individuelles, autant que l'espace le permet. Chaque cellule ressemblant à un petit cigare, est fabriquée à partir de morceaux de feuilles ou de fleurs découpées plus ou moins en forme de disque (d'où le nom anglais de leafcutter, « coupeuse de feuille » de l'espèce). Elle utilise par exemple des feuilles ou des fleurs de : hortensias, géraniums (Pelargonium zonale), euphorbes (Euphorbia), luzernes (Medicago), lilas (Syringa), vigne (Vitis). Bien que ces abeilles ne stockent pas de miel, les femelles déposent dans le nid un stock de pollen et nectar qui alimentera la larve. Elle est polylectique, c'est-à-dire qu'elle visite plusieurs sortes de fleurs (5 familles de plantes). Ses sources de pollen sont très variées et se répartissent dans les familles suivantes :
Chaque cellule contient une petite boule de pollen, du nectar et un œuf. La larve se développe rapidement, consommant sa provision de pollen et de nectar, puis entre en hibernation lorsque la provision est entièrement consommée. Au printemps suivant, la larve produit une pupe où elle complète son développement, puis sort du nid pour trouver un partenaire et se reproduire. Les femelles peuvent ravitailler jusqu'à 39 cellules. La période d'incubation est d'environ 30 jours et nécessite idéalement une température constante de plus de 30 °C.
Les larves de Megachile rotundata (ainsi que celles de l'abeille mellifère Apis mellifera) sont vulnérables aux champignons Ascosphaera aggregata et Ascosphaera apis, qui leur sont mortels[4],[5]. Ces deux pathogènes supportent très bien de très basses températures (-80 °C)[4].
Une abeille coucou, Coelioxys echinata (Förster 1853) (anciennement Coelioxys rufocaudata (Smith 1854)[6] ou Megachile rufocaudata (Smith 1854)[7], également appelée Coelioxys rufocaudata[8]) peut parasiter les autres mégachiles : les œufs du parasite éclosent les premiers et les larves qui en sortent détruisent les œufs de la victime. C'est aussi le cas de Coelioxys inermis (Kirby)[7]. L'hyménoptère (Eulophidae) Melittobia australica (Girault) (en) est un autre parasite de cette abeille[1].
De très grandes quantités d'abeilles découpeuses ont été importées en Hongrie depuis les États-Unis entre 1972 et 1978, mais en 1974-1975 l'introduction prévue n'a pas pu être effectuée à cause de leur parasitage trop important, notamment par Melittobia acasta[8], qui détruit les œufs de Megachile[9], et Coelioxys echinata[8], qui se sert des cellules vides de son hôte[9].
Cette espèce européenne a été importée et élevée aux États-Unis dans les années 1940[10] à fin de pollinisation des champs et fruitiers. Elle est localement devenue sauvage (marronnage) avant de se généraliser dans une grande partie de l'Amérique du Nord, et y est maintenant considérée comme une espèce indigène[11].
Megachile rotundata est de nos jours (en 2015) l'abeille solitaire la plus utilisée au monde. Son utilisation par l'industrie de la luzerne cultivée a triplé la production de graines[10] ; elle est la plus importante pollinisatrice de la luzerne porte-graines en Amérique du Nord[1]. Les producteurs de myrtilles (ou bleuets) l'utilisent également, mais M. rotundata est mal adaptée aux températures froides des nuits de printemps dans les régions productrices de cette baie au nord-est des États-Unis[10]. La densité recommandée par hectare serait de 49.420 abeilles découpeuses. Mais la reproduction naturelle est trop peu élevée pour maintenir les stocks nécessaires, et doit être compensée par l'achat annuel de stock[12].
L'abeille découpeuse (Megachile rotundata) ou abeille tapissière, est une espèce d'abeilles solitaires appartenant au genre Megachile. Ces abeilles construisent des loges à partir de morceaux de feuilles découpées de (luzernes, troènes, acacias...), dans lesquelles elles déposent leurs œufs.
Une de ses particularités est de découper avec une méthode spectaculaire des morceaux de feuilles tendres (découpe circulaire à ovale aux bords nets, toujours en bordure de feuille ou de foliole) qu'elle transporte ensuite en vol afin de fabriquer son nid constitué de logettes confectionnées à partir des morceaux de feuilles enroulées (aspect de petits cigares).
Un nombre important de feuilles peuvent ainsi être découpées, sur le robinier faux-acacia par exemple (photo ci-contre), sans conséquence apparente pour le végétal (la « cicatrisation » se fait rapidement, notamment grâce au fait que l'abeille ne coupe pas les nervures importantes).
Megachile rotundata Fabricius, 1787 è un imenottero apoideo appartenente alla famiglia Megachilidae[1], originario del bacino del Mediterraneo ed introdotto in Nord America negli anni '50.
È un apoideo lungo 8–10 mm, con capo robusto, ricoperto da una fitta peluria grigiastra.
Le femmine sono dotate di pungiglione, assente nei maschi, e presentano una struttura di raccolta del polline, formata da frange di peli (scopa), posta sotto l'addome.[2]
La specie è originaria del bacino del Mediterraneo.[1]
È stata introdotta accidentalmente nel Nord America già dal 1940, ed ha trovato favorevoli condizioni ambientali che ne hanno favorito la proliferazione, assumendo un importante ruolo come impollinatore delle coltivazioni di erba medica (Medicago sativa).[2] Più di recente è stata introdotta anche in Australia e Nuova Zelanda.[3][4]
All'inizio dell'estate i maschi escono dai nidi qualche giorno prima delle femmine e le attendono sui fiori presenti nell'ambiente, nutrendosi di nettare. Raggiunti dalle femmine, danno inizio ad un corteggiamento, che consiste in sfregamenti delle zampe e delle antenne sul corpo della femmina, al termine del quale avviene l'accoppiamento. Questa fase si protrae per più giorni ed ogni maschio si può accoppiare con più femmine. Subito dopo l'accoppiamento, la femmina individua un sito di nidificazione in una cavità preformata, spesso condivisa con altre conspecifiche, e inizia a raccogliere pezzetti di foglie fresche con cui tappezza il nido, ricavandovi diverse celle. In ciascuna delle celle viene ammassata una piccola quantità di polline, all'interno della quale viene deposto un uovo. Completata la ovodeposizione, l'ingresso del nido viene ostruito, sempre con pezzetti di foglie fresche.
Alla schiusura delle uova, la larva inizia a nutrirsi della riserva di polline accumulata dalla madre e ad ottobre, giunta allo stadio di larva matura, si imbozzola, per trascorrere in tale stadio l'inverno.
Nella primavera successiva, la larva riprenderà l'attività metabolica normale, sfarfallando all'inizio dell'estate.[5]
Megachile rotundata Fabricius, 1787 è un imenottero apoideo appartenente alla famiglia Megachilidae, originario del bacino del Mediterraneo ed introdotto in Nord America negli anni '50.
De luzernebehangersbij (Megachile rotundata) is een vliesvleugelig insect uit de familie Megachilidae. De wetenschappelijke naam van de soort is voor het eerst geldig gepubliceerd in 1793 door Fabricius.[1]
De bij is 7 à 9 mm lang, wat het een van de kleinste behangersbijen maakt. Behalve de grootte is de witte beharing een onderscheidend kenmerk.[2]
Oorspronkelijk komt de soort uit Midden- en Zuid-Europa, Noord-Afrika en Oost- tot Midden-Azië, maar tegenwoordig komt hij ook in de Lage Landen voor. In Nederland werd hij voor het eerst waargenomen in Groesbeek in 2009, België volgde in 2013. Nadien werd hij op nog meer Belgische plaatsen waargenomen, vooral in steden. Mogelijk komen ze vooral daar voor, doordat steden een steeds warmer microklimaat vormen. De soort lijkt zich er intussen goed gevestigd te hebben. De luzernebehangersbij komt ook voor in Noord-Amerika, Nieuw-Zeeland en Australië, waar ze is uitgezet als bestuiver.[2]
De bij maakt een nest in natuurlijke en kunstmatige plaatsen als holle stengels, gangen in dood hout en soms ook in de grond en in leemwanden. Met gekauwd plantenmateriaal sluiten ze de nesten af. In luzernevelden gebruiken ze daar blaadjes van die plant voor, vandaar ook de naam van het dier. De luzernebehangersbij wordt ook commercieel ingezet als bestuiver van deze plant. De bij is echter niet speciaal gebonden aan luzerne; ze wordt ook waargenomen op lelieachtigen, lipbloemen, schermbloemen, vetplanten en vlinderbloemen. In België beperkten waarnemen zich tot honingklaver, witte klaver, haagwinde en wit vetkruid.[2]
Bronnen, noten en/of referentiesMegachile rotundata är en art i överfamiljen bin och familjen buksamlarbin. Arten är ursprungligen europeisk, men har införts som pollinatör till många länder.
Arten är övervägande svart med smala, vita ränder mellan bakkroppssegmenten (tergiterna), och med ljusgrå päls på buken. Honan blir 8 till 9 mm lång och har vit behåring på första tergiten; övriga är svarthåriga (förutom de ovan nämnda vita ränderna). Buksidan är vitaktig; slutet på det 5:e, och hela 6:e buksegmentet (sterniterna) är dock svarthåriga. Hanen blir 7 till 8 mm, och har övervägande vitaktig behåring med undantag för tergit 3 till 4, som är svartpälsade.[3]
Megachile rotundata lever i skogsbryn, sluttningar, parker, trädgårdar, sand- och lertag. Den flyger från slutet av juni till mitten av augusti, och besöker blommande växter från familjerna flockblommiga växter, korgblommiga växter, fetbladsväxter, liljeväxter och ärtväxter (inte minst blålusern; det är ett av de få bina som kan tränga in i lusernblomman[4]).[3]
Honorna har gadd med giftapparat och använder denna för försvar. Som alla bin utom honungsbin dör de inte efter de har stuckit, utan kan sticka flera gånger. Giftet är dock inte särskilt starkt, och stinget anses svagare än en humlas.[4]
Honan bygger bon i murket trä, växtstänglar samt ler- och lössjord.[3] Bona används inte enbart för att föda upp larverna i; arten är ganska värmekrävande, och honorna tillbringar natten i sina bon. Mulna dagar med en temperatur under 20ºC tillbringar de i regel helt i boet.[4]
Megachile rotundata parar sig så fort de kommit ut ur pupporna på sommaren. Varje bo kan innehålla upp till ett 20-tal larvceller; honan klr dessa med löv, som hon skär ut i omkring 2,5 cm stora cirklar med käkarna. Ofta används blad från klättervin eller ask. Cellerna fylls med pollen som föda åt larverna. Arten övervintrar som vilolarv.[4]
I Nordamerika används biet som en kommersiell pollinatör, främst av blålusern (alfalfa)[4] och andra ärtväxter samt åkersenap; bina föds upp i konstgjorda bon, som körs omkring i stora, bilburna bihus till de olika fälten.[5]
Artens ursprungsområde är Europa, där den finns från Sydösteuropa till södra Finland och vidare österut till sydvästra Asien.[3][4] På grund av dess värde som pollinatör infördes den till Nordamerika på 1930-talet, senare även till Australien.[4][6] I Nordamerika finns den i USA från Virginia till Massachusetts och västerut till Kalifornien, samt i Kanada, där den främst utnyttjas som blåbärspollinatör.[1]
Megachile rotundata är en art i överfamiljen bin och familjen buksamlarbin. Arten är ursprungligen europeisk, men har införts som pollinatör till många länder.
Megachile rotundata là một loài Hymenoptera trong họ Megachilidae. Loài này được Fabricius mô tả khoa học năm 1793.[2] Đây là một loài ong châu Âu đã được du nhậpđến các khu vực khác nhau trên thế giới. Là một loài ong đơn độc, chúng không xây dựng các quần thể hoặc lưu trữ mật ong, nhưng là một loài thụ phấn rất hiệu quả của cỏ linh lăng, cà rốt, các loại rau khác và một số loại trái cây. Bởi vì điều này, nông dân thường sử dụng M. rotundata như một công cụ hỗ trợ thụ phấn bằng cách phân phối M. rotundata preupae xung quanh cây trồng của họ. Mỗi con cái xây tổ của riêng mình, tổ được xây dựng trong những cây cổ thụ hoặc các hang trong gỗ. Là một con ong cắt lá, những tổ này được lót bằng những chiếc lá cắt. Những con ong này ăn phấn hoa và mật hoa và hiển thị dị hình tình dục. Loài này đã được biết là cắn và đốt, tuy nhiên nó không gây nguy hiểm chung trừ khi nó bị đe dọa hoặc gây hại và vết chích của nó được mô tả là đau đớn bằng một nửa loài ong mật.
Megachile rotundata là một loài Hymenoptera trong họ Megachilidae. Loài này được Fabricius mô tả khoa học năm 1793. Đây là một loài ong châu Âu đã được du nhậpđến các khu vực khác nhau trên thế giới. Là một loài ong đơn độc, chúng không xây dựng các quần thể hoặc lưu trữ mật ong, nhưng là một loài thụ phấn rất hiệu quả của cỏ linh lăng, cà rốt, các loại rau khác và một số loại trái cây. Bởi vì điều này, nông dân thường sử dụng M. rotundata như một công cụ hỗ trợ thụ phấn bằng cách phân phối M. rotundata preupae xung quanh cây trồng của họ. Mỗi con cái xây tổ của riêng mình, tổ được xây dựng trong những cây cổ thụ hoặc các hang trong gỗ. Là một con ong cắt lá, những tổ này được lót bằng những chiếc lá cắt. Những con ong này ăn phấn hoa và mật hoa và hiển thị dị hình tình dục. Loài này đã được biết là cắn và đốt, tuy nhiên nó không gây nguy hiểm chung trừ khi nó bị đe dọa hoặc gây hại và vết chích của nó được mô tả là đau đớn bằng một nửa loài ong mật.
Пчела-листорез люцерновая[1] (Megachile rotundata, англ. Alfalfa leafcutting bee)[2] — вид пчёл-листорезов из семейства Megachilidae (подрод Eutricharaea). Важный опылитель, разводимый в промышленных масштабах[3]. Внесена в Красную книгу Ставропольского края как вид, нуждающийся в охране[4].
Европа, Сибирь, Дальний Восток, Монголия, Северная Африка. Интродуцированы во многие регионы как важный опылитель люцерны (alfalfa):[5] Северная и Южная Америка, Новая Зеландия (с 1971), Австралия (с 1987)[6][7][8][9].
Одиночные пчёлы. Ячейки своих гнёзд, содержащих одно яйцо и запас пыльцы, выстилают кусочками листьев люцерны, роз, шиповника, бирючины. Эти вырезаемые ими кусочки имеют округлую форму и вреда растению такие надрезы не приносят, так как пчёлы не нарушают их сосудистую систему. Длина около 1 см. На тергитах брюшка имеются светлые перевязи из прилегающих волосков. Клипеус имеет густую пунктировку[10]. Мед и крупных колоний не образует, но является важным опылителем многих цветковых растений, включая такие важные культуры, как люцерна посевная, морковь и другие[11]. При ввозе в страну коконов люцерновой пчелы-листореза действуют специальные ветеринарные правила, утверждаемые Минсельхозпродом РФ[12].
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(справка) Пчела-листорез люцерновая (Megachile rotundata, англ. Alfalfa leafcutting bee) — вид пчёл-листорезов из семейства Megachilidae (подрод Eutricharaea). Важный опылитель, разводимый в промышленных масштабах. Внесена в Красную книгу Ставропольского края как вид, нуждающийся в охране.