Bombus lapidarius

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Red-tailed bumblebee
Bombus lapidarius queen - Echium vulgare - Keila.jpg
Queen
Bombus lapidarius drone - Carduus crispus - Keila.jpg
Drone
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Apidae
Genus: Bombus
Subgenus: Melanobombus
Species:
B. lapidarius
Binomial name
Bombus lapidarius

Bombus lapidarius is a species of bumblebee in the subgenus Melanobombus . Commonly known as the red-tailed bumblebee, B. lapidarius can be found throughout much of Central Europe. Known for its distinctive black and red body, this social bee is important in pollination. [2]

Contents

Taxonomy and phylogeny

The red-tailed bumblebee is a part of the order Hymenoptera, family Apidae, and the genus Bombus , which includes many species including Bombus terrestris , Bombus lucorum , and Bombus hypnorum . [3]

Description and identification

Worker female Bombus lapidarius - Melilotus officinalis - Tallinn.jpg
Worker female
Drone Bombus lapidarius (male) - Centaurea scabiosa - Keila.jpg
Drone
Worker female Bombus lapidarius - Arctium tomentosum - Keila.jpg
Worker female
Red-tailed cuckoo bumblebee parasitizes the nests of the red-tailed bumblebee Bombus rupestris - Trifolium pratense - Keila.jpg
Red-tailed cuckoo bumblebee parasitizes the nests of the red-tailed bumblebee

The red-tailed bumblebee is typically distinguished by its black body with red markings around the abdomen. Worker females and the queen look similar, though the queen is much larger than the worker females. Males typically have the red and black coloration with a yellow band around the abdomen and yellow markings on the face. Further, B. lapidarius tend to have a medium-sized proboscis, which is significant in that it allows the species to be a good pollinator. [4] These bees do not typically form extensive or complex colonies. [5] Nests usually only contain a few hundred bees at most, with an average colony consisting of about 100 to 200 worker bees. [6]

Distribution and habitat

Bombus lapidarius is found throughout Europe, including Britain and Ireland, as well as parts of Greece, [7] Germany, Sweden and Finland. [8] The species has a fairly wide distribution, typically being found in temperate regions. B. lapidarius nests have been found in many different habitats, but the bees usually prefer open terrain to more heavily forested landscapes. [9] They can fly over 1500 meters to better forage for food.

Colony cycle

Red-tailed bumblebees appear in the summer months of June, July, and August. [10] Colonies are initiated via the queen, where workers and males follow roles to keep the colony thriving. Though there is a hierarchy between the queen and the rest of the colony, there does not appear to be a hierarchy among the workers themselves. [11]

Behavior

Brood

Social bees, including Bombus lapidarius, are able to produce a great deal of heat due to the contraction of their thoracic flight muscles. They are able to use this heat to help warm and incubate their brood. This also allows them to help regulate the temperature of the nest generally. [12]

Courtship behavior

Red-tailed bumblebee males utilise sexual pheromones to attract females. Males will fly around and mark spots with the pheromone compounds (Z)-9-hexadecenol and hexadecanal via their labial gland. These secretions are highly species-specific, and thus likely greatly reduce inter-species mating. B. lapidarius typically fly and secrete above the treetops, which are more affected by the wind and the sun. Therefore, this species often has to secrete more pheromone than other species to be effective. [13] These compounds have been found in trace amounts in the air around the areas that individuals have scent marked. [14] Different populations in diverse locations (specifically Southern Italy, the Balkans, and Central-Eastern Europe) have experienced genetic differentiation in pheromone composition. [2]

Pheromones

B. lapidarius pheromones are believed to be “precopulatory signals”, or are used in an attempt to attract mates. These pheromones are often copied by cuckoo species. [15] Red-tailed bumblebee queens also appear to secrete pheromones. Functionally, these pheromones appear to inhibit ovarian development in worker bees, though the true function of the queens' pheromones are still unclear. It is known, however, that their chemical composition differs significantly from worker pheromones. [16]

Sex allocation

As the red-tailed bumblebee is a member of the Hymenoptera order, the bee displays interesting sex allocation tactics. Studies have suggested that it is the workers, rather than the queen, who control sex allocation. [17] As such, Hymenoptera are known for having haploid males and diploid females. [18]

Foraging patterns

B. lapidarius has been found to be a fairly dominant species in foraging and has been found to travel as far as 1750 meters to forage for resources such as Phacelia tenuifolia. [10] However, it appears that individual bumblebees vary greatly in the distance they traveled for foraging. One study extensively studied foraging behavior in B. lapidarius. In an almost barren, treeless basin in Germany, the study found nests of the red-tailed bumblebee as well as two other Bombus species within one hundred meters of each other. Each species had equal resource availability. Researchers marked the foraging bees, with almost 80% of all of the foraging bees eventually marked for study. [10] It was found that foraging time was greatest at around a five hundred meter radius around the nest, but time decreased as distance increased past the five hundred meter mark. Further, flight distance was very different among different individuals, reinforcing the idea that specific bees are bred for specific tasks, and that some are more skilled than others. Outside of the differences between individual bees, differences between species were found as well. [10] B. lapidarius, for example, was found to typically forage within a five hundred meter radius of its nest, but some individuals ranged much farther than this, as far as 1,500 meters away. Moreover, the red-tailed bumblebee displayed high “patch fidelity”, indicating that an individual bee was likely to return to a specific location. This species of bee thus can loosely be described as a “long distance forager”, but does not travel as far as some other Bombus species, thus it is typically described as having an intermediate foraging distance. Further, the study noted that body size appeared to be a factor in how far a bee might be willing to travel and concluded that foraging distance would differ most between species. [10]

Males and workers

Males have been found to travel much farther than workers. [19] This behavior may help lead to greater genetic variation, as populations appear to be diverse and avoid inbreeding. Workers, in comparison, tend to stay closer to the nest. Workers are often invested in cell building within the nest. [11] Furthermore, B. lapidarius workers do not appear to have a hierarchy between them, which differs from many other species. Workers typically build cells, while the queen asserts her dominance over each egg cell. However, since B. lapidarius workers often eat the queen’s eggs, this decreases the queen’s dominance. Further, workers that are more aggressive have been found to be more likely to have ovaries, as well. [11]

Diet

Red-tailed bumblebees typically eat pollen and nectar. [13] Workers will sometimes attempt to eat the eggs that the queen has laid. [11] The queen makes a valiant effort to prevent this from happening, but the workers are frequently successful in their attempt. Though the queen does not attempt to injure workers engaging in this activity, she does threaten them with her mandible or sometimes hits them with her head. [11] Further study may be required to better understand this behavior.

The bees have been found to move between specific species of flower, but ignore other species that could be equally rewarding. One study showed that these bees will stay at a particular flower or food source longer with increased levels of nectar available. However, the time spent at any particular flower did not change with different levels of pollen. [20]

Interaction with other species

Parasites

Bombus lapidarius often experiences parasites, including different species from the Psithyrus subgenus which attempt to usurp its nest. [21] All cuckoo bumblebee species lack a worker caste—instead the female queen cuckoo bee invades the nest of a host species and lays her eggs there. These cuckoo bees utilize different mechanisms via chemical recognition systems, including mimicry and repulsion, to invade B. lapidarius nests. By mimicking both physical traits and chemical secretions, cuckoos have evolved to mimic B. lapidarius species in particular. Typically, species avoid cuckoo parasitism by emitting complex hydrocarbons, which species such as the red-tailed bumblee use to recognize each other. [21] However, cuckoos are sometimes able to copy them in order to introduce themselves into a host colony. Even if cuckoos do not match the B. lapidarius traits in these ways, parasitism can still be achieved via repulsion. Cuckoos can produce a worker repellent, thus allowing the parasitic species to survive within the group. Either hosts raise these cuckoos as their own, or cuckoos invade and become a part of the B. lapidarius colony. Occasionally, Psithyrus queens eat B. lapidarius eggs if their own brood is becoming nutritionally deficient. [21]

Mutualism

Red-tailed bumblebees are very important in the pollination of many different species of flower and crops. [22] B. lapidarius was found to forage and pollinate at higher temperatures than other Bombus species. [23] This is important for understanding when and where pollination is most likely to occur.

Human importance

Stings

This species is a type of bumblebee, and thus has the ability to sting. [2]

Agriculture

The red-tailed bumblebee is a very important pollinator. For many plants, such as certain species of Viscaria, only bees and butterflies have proboscides long enough to pollinate effectively. [24] For example, studies have showm that B. lapidarius have a high feeding density relative to other bee species. [24] Bombus lapidarius is important in pollinating many other species, including Centaurea scabiosa . [25] A study found that though Apis mellifera was also involved in pollination of this species, B. lapidarius greatly outnumbers Apis and other bee species in pollination. Though initially attracted to flowers by the color, the scent is what drives attention as the bees approach flowers. It has been suggested that some individuals are better able to interpret differences in scent in the flowers than others. [25] These differences in ability may have evolved as different types of bees developed specific roles within the colony. Other experiments have indicated that body size is an important factor in how bumblebees pollinate. It appears that size affects the frequency of a bee's visits to flowers, as well as its pollination skill. Smaller bees seem to pollinate more effectively than larger bees. Nevertheless, there does not appear to be a correlation between floral display size and body size. It has therefore been suggested that bumblebees of all different sizes respond in the same way to floral display size. [26]

Conservation status

Red-tailed bumblebees rank among the most common and most recognized bumblebees of Central Europe, but rarer species, such as Bombus ruderarius , have a similar appearance.

This species is widespread across Ireland, though some evidence indicates that the species is declining in agricultural grasslands. [27] It is considered Near Threatened in Ireland. [28]

Additionally, it has been suggested that different species of bumblebee understand their surroundings according to different scales. This has important implications for conservation—the differences in species behavior is significant in understanding resource range and differences in foraging areas. Understanding these concepts is vital to conservation and biodiversity. [29] Thus, these bees specifically are very important to agriculture, as they are so important in pollination. Therefore, conservation of B. lapidarius is important to understand.

Related Research Articles

<span class="mw-page-title-main">Bumblebee</span> Genus of insect

A bumblebee is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related genera are known from fossils. They are found primarily in higher altitudes or latitudes in the Northern Hemisphere, although they are also found in South America, where a few lowland tropical species have been identified. European bumblebees have also been introduced to New Zealand and Tasmania. Female bumblebees can sting repeatedly, but generally ignore humans and other animals.

<i>Bombus terrestris</i> Species of bee

Bombus terrestris, the buff-tailed bumblebee or large earth bumblebee, is one of the most numerous bumblebee species in Europe. It is one of the main species used in greenhouse pollination, and so can be found in many countries and areas where it is not native, such as Tasmania. Moreover, it is a eusocial insect with an overlap of generations, a division of labour, and cooperative brood care. The queen is monogamous which means she mates with only one male. B. terrestris workers learn flower colours and forage efficiently.

<span class="mw-page-title-main">Early bumblebee</span> Species of bee

The early bumblebee or early-nesting bumblebee is a small bumblebee with a wide distribution in most of Europe and parts of Asia. It is very commonly found in the UK and emerges to begin its colony cycle as soon as February which is earlier than most other species, hence its common name. There is even some evidence that the early bumblebee may be able to go through two colony cycles in a year. Like other bumblebees, Bombus pratorum lives in colonies with queen and worker castes. Bombus pratorum queens use aggressive behavior rather than pheromones to maintain dominance over the workers.

<i>Bombus hypnorum</i> Species of bee

The tree bumblebee or new garden bumblebee is a species of bumblebee common in the European continent and parts of Asia. Since the start of the twenty-first century, it has spread to Great Britain. These bumblebees prefer habitats that others do not, allowing them to pollinate flowers in areas that many other species do not get to.

<i>Bombus hyperboreus</i> Species of bee

Bombus hyperboreus is a species of Arctic bumblebee with a circumpolar distribution. The species is primarily found in the arctic areas of Greenland, northern Scandinavia, and Russia. In 2015 the nearctic species, Bombus natvigi, was separated from this species, based on genetic analysis. Accordingly, Bombus hyperboreus is limited to the Palaearctic, despite older literature listing this species as occurring in the Nearctic.

<i>Bombus vestalis</i> Species of bee

Bombus vestalis, the vestal cuckoo bumblebee, is a species of cuckoo bumblebee that lives in most of Europe, as well as North Africa and western Asia. It is a brood parasite that takes over the nests of other bee species. Its primary host is Bombus terrestris. After its initial classification as Psithyrus vestalis, this bumblebee recently was reclassified into the genus Bombus, subgenus Psithyrus.

<i>Bombus citrinus</i> Species of bee

Bombus citrinus is a species of bumblebee known commonly as the lemon cuckoo bumblebee due to its lemon-yellow color. It is native to eastern North America.

<i>Bombus rupestris</i> Species of bee

Bombus rupestris is a species of cuckoo bumblebee present in most of Europe except Iceland. In the Balkans it is found in montane and alpine habitats northwards from Central Greece. It is also found in Turkey.

<i>Bombus sylvestris</i> Species of bee

Bombus sylvestris, known as the forest cuckoo bumblebee or four-coloured cuckoo bee, is a species of cuckoo bumblebee, found in most of Europe and Russia. Its main hosts are Bombus pratorum, Bombus jonellus, and Bombus monticola. As a cuckoo bumblebee, Bombus sylvestris lays its eggs in another bumblebee's nest. This type of bee leaves their young to the workers of another nest for rearing, allowing cuckoo bumblebees to invest minimal energy and resources in their young while still keeping the survival of their young intact.

<i>Bombus bohemicus</i> Species of bee

Bombus bohemicus, also known as the gypsy's cuckoo bumblebee, is a species of socially parasitic cuckoo bumblebee found in most of Europe with the exception of the southern Iberian Peninsula and Iceland. B. bohemicus practices inquilinism, or brood parasitism, of other bumblebee species. B. bohemicus is a generalist parasite, successfully invading several species from genus Bombus. The invading queen mimics the host nest's chemical signals, allowing her to assume a reproductively dominant role as well as manipulation of host worker fertility and behavior.

<i>Bombus hortorum</i> Species of bee

Bombus hortorum, the garden bumblebee or small garden bumblebee, is a species of bumblebee found in most of Europe north to 70°N, as well as parts of Asia and New Zealand. It is distinguished from most other bumblebees by its long tongue used for feeding on pollen in deep-flowered plants. Accordingly, this bumblebee mainly visits flowers with deep corollae, such as deadnettles, ground ivy, vetches, clovers, comfrey, foxglove, and thistles. They have a good visual memory, which aids them in navigating the territory close to their habitat and seeking out food sources.

<i>Bombus lucorum</i> Species of bee

Bombus lucorum, the white-tailed bumblebee, is a species of bumblebee, widespread and common throughout Europe. This name has been widely used for a range of nearly identical-looking or cryptic species of bumblebees. In 1983, Scholl and Obrecht even coined the term Bombus lucorum complex to explain the three taxa that cannot be easily differentiated from one another by their appearances. A recent review of all of these species worldwide has helped to clarify its distribution in Europe and northern Asia, almost to the Pacific. B. lucorum reaches the Barents Sea in the North. However, in southern Europe, although found in Greece it is an upland species with its distribution never quite reaching the Mediterranean.

<i>Bombus pensylvanicus</i> Species of bee

Bombus pensylvanicus, the American bumblebee, is a threatened species of bumblebee native to North America. It occurs in eastern Canada, throughout much of the Eastern United States, and much of Mexico.

Two-spotted bumble bee Species of bee

The two-spotted bumble bee is a species of social bumble bee found in the eastern half of the United States and the adjacent south-eastern part of Canada. In older literature this bee is often referred to as Bremus bimaculatus, Bremus being a synonym for Bombus. The bee's common name comes from the two yellow spots on its abdomen. Unlike many of the other species of bee in the genus Bombus,B. bimaculatus is not on the decline, but instead is very stable. They are abundant pollinators that forage at a variety of plants.

<i>Bombus vosnesenskii</i> Species of bee

Bombus vosnesenskii, the yellow-faced bumblebee, is a species of bumblebee native to the west coast of North America, where it is distributed from British Columbia to Baja California. It is the most abundant species of bee in this range, and can be found in both urban and agricultural areas. Additionally, B. vosnesenskii is utilized as an important pollinator in commercial agriculture, especially for greenhouse tomatoes. Though the species is not currently experiencing population decline, urbanization has affected its nesting densities, and early emergence of the B. vosnesenskii has been implicated in the increasing lack of bee diversity on the West coast.

<i>Bombus occidentalis</i> Species of bee

Bombus occidentalis, the western bumblebee, is one of around 30 bumblebee species present in the western United States and western Canada. A recent review of all of its close relatives worldwide appears to have confirmed its status as a separate species.

<i>Bombus fervidus</i> Species of bee

Bombus fervidus, the golden northern bumble bee or yellow bumblebee, is a species of bumblebee native to North America. It has a yellow-colored abdomen and thorax. Its range includes the North American continent, excluding much of the southern United States, Alaska, and the northern parts of Canada. It is common in cities and farmland, with populations concentrated in the Northeastern part of the United States. It is similar in color and range to its sibling species, Bombus californicus, though sometimes also confused with the American bumblebee or black and gold bumblebee. It has complex behavioral traits, which includes a coordinated nest defense to ward off predators. B. fervidus is an important pollinator, so recent population decline is a particular concern.

<i>Bombus affinis</i> Species of bee

Bombus affinis, commonly known as the rusty patched bumble bee, is a species of bumblebee endemic to North America. Its historical range in North America has been throughout the east and upper Midwest of the United States, north to Ontario, Canada, where it is considered a "species at risk", east to Quebec, south to Georgia, and west to the Dakotas. Its numbers have declined in 87% of its historical habitat range. On January 10, 2017, the United States Fish and Wildlife Service placed B. affinis on the list of endangered species, making the rusty patched bumblebee the first bee to be added to the list in the continental United States.

<i>Bombus terricola</i> Species of bee

Bombus terricola, the yellow-banded bumblebee, is a species of bee in the genus Bombus. It is native to southern Canada and the east and midwest of the United States. It possesses complex behavioral traits, such as the ability to adapt to a queenless nest, choose which flower to visit, and regulate its temperature to fly during cold weather. It was at one time a common species, but has declined in numbers since the late 1990s, likely due to urban development and parasite infection. It is a good pollinator of wild flowers and crops such as alfalfa, potatoes, raspberries, and cranberries.

<i>Bombus vancouverensis</i> Species of bee

Bombus vancouverensis is a common species of eusocial bumblebee of the subgenus Pyrobombus. B. vancouverensis inhabits mountainous regions of western North America, where it has long been considered as a synonym of Bombus bifarius, and essentially all of the literature on bifarius refers instead to vancouverensis. B. vancouverensis has been identified as one of the two species of bumblebee observed to use pheromones in kin recognition. The other is the frigid bumblebee, Bombus frigidus.

References

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