Diversity
Bombylius
, commonly known as bee-flies, is a genus that includes 3 subgenera and an estimated
335 subspecies worldwide. Bee-flies are mimics of bumblebees and other unrelated bees.
Larvae are parasitoids that feed on the eggs, larvae, and stored pollen of solitary
bees. Bee-flies are important pollinators.
Geographic Range
Bee flies are nearly worldwide in distribution. There are approximately 280 subspecies
in the United States.
Large bee-flies
are the most common species of the genus and are found across the northern hemisphere.
There have been 23 subspecies recorded in the Ethiopian, 150 in the Palearctic, 109
in the Nearctic, 12 in the Neotropical, and 11 in the Oriental regions.
- Biogeographic Regions
- nearctic
- palearctic
- oriental
- ethiopian
- neotropical
Habitat
Bee-flies are found in warm regions where flowering plants live. They can be seen
on the ground, near flowers, and in bushes during the day. At night, they shelter
in the crowns of trees.
- Habitat Regions
- temperate
- terrestrial
- Terrestrial Biomes
- savanna or grassland
- forest
Physical Description
Bee-flies are a genus that imitates various bees, such as
bumblebees
. Similarly to
bumblebees
, bee-flies are densely hairy with body colorings ranging from black to orange. The
hairs are often a lighter color than the body, except one subspecies that is covered
with black hair. Unlike bees, bee-flies have a long proboscis, four long legs, short
antennae, and two wings. They do not have a stinger. Bee-flies are medium-sized, but
subspecies vary in size from 8-16 mm. The females of some subspecies are larger than
the males. Larvae look like grubs.
- Other Physical Features
- ectothermic
- bilateral symmetry
- Sexual Dimorphism
- female larger
Development
Eggs are laid individually at the entrances of solitary bee nests. The eggs hatch
and the larvae seek out and feed upon stored pollen, bee eggs, and bee larvae. Once
the larvae are grown, they pupate and remain in the bee nest until the next spring.
- Development - Life Cycle
- metamorphosis
Reproduction
Bee-flies mate and lay eggs during the spring to early summer. After mating, they
seek out the nests of solitary bees to lay eggs. Once a nest has been found, the female
hovers over the entrance and drops an individual egg. This process repeats. The eggs
hatch, feed, pupate, then wait for the next spring to arrive. The larvae are parasitic.
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- oviparous
No information about parental involvement for this genus was found.
- Parental Investment
- no parental involvement
Lifespan/Longevity
Little information is available on the lifespan of bee-flies due to their high mobility.
The lifespan has been determined to be greater than two weeks because eggs appear
at the earliest two weeks after adults. Bee-flies are found during spring to early
summer.
Behavior
Bee-flies are a genus of solitary flies. They make a buzzing sound when flying, are
very fast flyers, and are able to hover in mid-air.
Members of the genus are most active during the day when the weather is sunny and
warm. They are typically found on the ground and flying in forests and bushes. When
the weather is cloudy, bee-flies will sit on the ground in an attempt to warm themselves.
If the sun reappears, the bee-flies will start to fly again. At night, they avoid
the ground and bushes, as they seem to hide in the crowns of trees.
Communication and Perception
Bee-flies use the sense of sight, touch, sound, and chemical receptors to get information
and communicate.
Food Habits
Adults feed primarily on nectar. Pollen has been found in the systems of adults, but
it is unknown if it was eaten intentionally. Larvae are parasitoids that feed on the
eggs, larvae, and stored pollen of host bees.
- Primary Diet
- herbivore
Predation
Bee-flies are mimics of bumblebees (
Bombus
species).
- Anti-predator Adaptations
- mimic
Ecosystem Roles
Adults are pollinators of a large variety of flowers. Larvae are parasitoids of bees
and feed on bee larvae. Instead of bees, the larvae of some species are parasitic
to the eggs and larvae of
locusts
,
fly
pupa, and
caterpillars
.
- Ecosystem Impact
- pollinates
- parasite
Economic Importance for Humans: Positive
Bee-flies are important pollinators. They visit purple, violet, blue, and white flowers
more often than other colors.
Lungwort
,
purple gromwell
,
common bugloss
, and
European stickseed
are commonly visited plants.
- Positive Impacts
- pollinates crops
Economic Importance for Humans: Negative
Conservation Status
No special status.
Additional Links
Contributors
Deena Hauze (author), Animal Diversity Web Staff.
- Nearctic
-
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- Palearctic
-
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
- oriental
-
found in the oriental region of the world. In other words, India and southeast Asia.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- tropical savanna and grassland
-
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
-
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
-
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- metamorphosis
-
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- internal fertilization
-
fertilization takes place within the female's body
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- diurnal
-
- active during the day, 2. lasting for one day.
- motile
-
having the capacity to move from one place to another.
- nomadic
-
generally wanders from place to place, usually within a well-defined range.
- solitary
-
lives alone
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- parasite
-
an organism that obtains nutrients from other organisms in a harmful way that doesn't cause immediate death
- herbivore
-
An animal that eats mainly plants or parts of plants.
- nectarivore
-
an animal that mainly eats nectar from flowers
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
References
Beal, F. 1912. Food of our more important flycatchers. U.S. Department of Agriculture, Biological Survey Bulletin , 44.
Evenhuis, N., D. Greathead. 1999. World Catalog of Bee Flies (Diptera: Bombyliidae) . Leiden: Backhuys Publishers. Accessed May 08, 2020 at http://hbs.bishopmuseum.org/bombcat/ .
Kastinger, C., A. Weber. 2001. Bee-flies (Bombylius spp., Bombyliidae, Diptera) and the pollination of flowers. Flora , 196: 3-25.
Moisset, B. 2020. "Bee Flies (Bombylius spp.)" (On-line). U.S. FOREST SERVICE. Accessed May 08, 2020 at https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/bee_flies.shtml .
Riley, . 1881. The American Naturalist. Larval Habits of Bee-Flies , 15(6): 438-447.
Roskov, Y., G. Ower, T. Orrell, D. Nicolson, N. Bailly, P. Kirk, T. Bourgoin, R. DeWalt, W. Decock, E. van Nieukerken, L. Penev. 2020. "Species 2000 & ITIS Catalogue of Life" (On-line). Accessed May 09, 2020 at www.catalogueoflife.org/col .
2012. "Genus Bombylius" (On-line). Bug Guide. Accessed May 08, 2020 at https://bugguide.net/node/view/9490#synonyms .