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Villa alternata

What do they look like?

This bee fly has a short mouthpart called a proboscis. They are covered in hairs and scales that vary from golden yellow to black and white. Their are usually tufts of black and white or yellowish hair at the end of the body. The wings of Villa alternata are clear, except for some brown where the wings attach to the body. Since they live in so many different habitats, Villa alternata may look slightly different from region to region. Those bee flies that live in areas with high temperatures and little rain are usually lighter in color than those from places with lower temperatures and more rain. (Falck, 2009; Kits, et al., 2008)

  • Range length
    10 to 17 mm
    0.39 to 0.67 in

Where do they live?

Villa alternata is a species of bee fly found on every continent except Antarctica. (Greathead, 1981)

What kind of habitat do they need?

Since Villa alternata is found on all continents except Antarctica, it is found in a large variety of habitats with varying rainfall, temperature and soil types. Its habitat must have noctuid moths and/or tenebrionid beetles, which the larvae parasitize to grow and develop. These bee flies are found in dunes, sandy scrub regions, forests, grasslands, taiga, marshes, and bogs. (Falck, 2009; Hull, 1973; Kits, et al., 2008; Yeates and Lambkin, 1994)

How do they grow?

Bee flies go through complete metamorphosis, with life stages of egg, larva, pupa, and adult. Bee fly larva has two very different stages. The first larvae stage is active and looks for a host to parasitize. The larvae commonly parasitizes the larvae of Noctuid moths (Noctuidae) or tenebrionid beetles (Tenebrionidae). Once this first stage larva finds a host to feed on, it becomes a second stage larvae that does not move much and feeds on the host insect. After larval development is complete, they become pupa. Pupae have spines and spikes that let them break free when the host insect forms a pupa. The bee fly pupa drills out of the nest, where it emerges as a flying adult. (Falck, 2009; Yeates and Lambkin, 2013)

How do they reproduce?

When looking to mate, female bee flies fly to high places such as the top of hills. Males also gather at these high places. This is called "hilltopping". Females usually choose male mates, but sometimes males will just grab females as they fly past. Mating takes about 100 minutes on average. Males have territories that they defend from other males. They will get in fights while flying and collide in mid-air. The males have spines on their wings which cause cuts on the bodies of the other males that they fight with. (Yeates and Dodson, 1990)

After mating, Villa alternata females find a crack or hole in the ground and position themselves to make a chamber in the sand. The females then fill this chamber with sand, dust, saw-dust, or other fine particles. This is meant to prevent the eggs from sticking together. To lay her eggs, the female flicks the end of her abdomen so that the eggs fly off into the sand chamber. Hundreds of eggs are laid in the sand chamber in a couple of hours. Villa alternata appears commonly in the months of May to August in North American temperate climates, so reproduction likely takes place in the spring and summer. (Falck, 2009; Toft, 1983)

  • Breeding season
    Mating takes place in the spring and summer.

Male bee flies might supply nutrients to the female during mating, which would be used for the development of the offspring. Females make a sand chamber for the eggs, and also collect small particles like sand or saw dust so the eggs will not stick together. After the eggs are laid, neither parent provides any more care. (Yeates and Greathead, 1997)

  • Parental Investment
  • pre-hatching/birth
    • provisioning

How long do they live?

Adults likely live for about a month after emerging from pupation, but this is not known for sure. (Toft, 1983)

  • Average lifespan
    Status: wild
    1 months

How do they behave?

Bee flies are very mobile, hovering or flying in their adult life. Bee flies spend their time alone except when they mate or when males partake in territorial fights. Males fight with other males over their territories, by crashing in the air. Bee fly males have spines on their wings that can cut into the bodies of the males they are fighting. Bee flies are active during the day, especially sunny days. Larvae stay in groups in the host insect before emerging. (Kits, et al., 2008; Yeates and Dodson, 1990)

How do they communicate with each other?

Not much is known about how these bee flies communicate or how they sense the environment around them. They likely use vision and detect chemicals. First stage larvae have to find insects somehow that they can parasitize to survive, but it is not know how the larvae find the hosts. (Feener and Brown, 1997)

What do they eat?

Villa alternata feeds on nectar and pollen. It feeds on small flowers such as Chrysothamnus viscidiflorus in the common Asteraceae family. Female bee flies spend large amounts of time feeding, up to 8 times that of males. (Toft, 1983)

  • Animal Foods
  • insects
  • Plant Foods
  • nectar
  • pollen

What eats them and how do they avoid being eaten?

Birds are predators of Villa alternata. Bee flies can escape predators sometimes because they look like bees and wasps. They have similar colors and similar body shapes as many wasps and bees. If a predator thinks an insect is a wasp or bee, which can sting and cause pain for the predator, then they will usually avoid trying to eat it. This is helpful for bee flies, since predators may avoid eating them, thinking they are bees. (Yeates and Lambkin, 1994; Yeates and Lambkin, 2013)

  • These animal colors help protect them
  • mimic
  • Known Predators

What roles do they have in the ecosystem?

Villa alternata larvae are parasites of Noctuidae moths and Tenebrionidae beetles. Noctuidae moths are crop pests, so by being parasites of these moths, Villa alternata can decrease their population size and prevent damage to the crops and other plants. Tenebrionidae beetles feed on a variety of grasses, so Villa alternata can prevent the beetles from eating these grasses, allowing the grasses to grow. These bee flies are also eaten by birds. (Hull, 1973; Kits, et al., 2008; Sheldon and Beedlow, 1988; Yela and Herrera, 1993)

Species (or larger taxonomic groups) used as hosts by this species

Do they cause problems?

These bee flies do not cause any problems for humans.

How do they interact with us?

The larvae of Villa alternata are parasites of Noctuidae moths. The caterpillars of Noctuidae moths are known to eat and destroy many agricultural crops. Since the larvae end up killing the moths, these bee flies can decrease the amount of Noctuidae moths. This decreases the amount of crop damage that the moths can do, which is helpful in preventing economic loss for people. Bee flies also pollinate plants that they feed from, some of which may be used by humans. (Wiegmann, 2011)

  • Ways that people benefit from these animals:
  • controls pest population

Are they endangered?

Villa alternata is not an endangered species. (McGinley, 1993)

Some more information...


Jayna Sames (author), University of Michigan Biological Station, Brian Scholtens (editor), University of Michigan Biological Station, Angela Miner (editor), Animal Diversity Web Staff.


Falck, M. 2009. The Norwegian species of Villa Lioy, 1864 (Diptera, Bombyliidae). Norwegian Journal of Entomology, 56: 120–130.

Feener, D., B. Brown. 1997. Diptera as Parasitoids. Annual Review of Entomology, 2: 73-97.

Greathead, D. 1981. The Villa group of genera in Africa and Eurasia with a review of the genera comprising Thyridanthrax sensu Bezzi 1924 (Diptera: Bombyliidae). Journal of Natural History, 15:2: 309-326.

Hull, F. 1973. Bee flies of the world: the genera of the family Bombyliidae (1973). Washington D.C.: Smithsonian Institution Press.

Kits, J., S. Marshall, N. Evenhuis. 2008. The bee flies (Diptera: Bombyliidae) of Ontario, with a key to the species of eastern Canada. Canadian Journal of Arthropod Identification, 6: 1-52.

McGinley, R. 1993. Where's the management in collection's management: planning for improved care, greater use, and growth of collections.. National Museum of Natural History, 1: 309-338.

Sheldon, J., P. Beedlow. 1988. Diets of Darkling Beetles (Coleoptera: Tenebrionidae) Within a Shrub-Steppe Ecosystem. Entomological Society of America, 81: 782-791.

Toft, K. 1983. Community patterns of neetivorous adult parasitoids (Diptera, Bombyliidae) on their resources. Oecologia, 57: 200-215.

Wiegmann, B. 2011. Overcoming the effects of rogue taxa: Evolutionary relationships of the bee flies. PloS Currents, 5: 1-13.

Yeates, D., D. Greathead. 1997. The evolutionary pattern of host use in the Bombyliidae (Diptera): a diverse family of parasitoid flies.. Biological Journal of the Linnean Society, 50: 149-185.

Yeates, D., G. Dodson. 1990. The Mating System of a Bee Fly (Diptera: Bombyliidae). I. Non-Resource-Based Hilltop Territoriality and a Resource-Based Alternative. Journal of Insect Behavior, 3: 1-15.

Yeates, D., C. Lambkin. 1994. "Bombyliidae" (On-line). Tree of Life Web Project. Accessed July 24, 2013 at

Yeates, D., C. Lambkin. 2013. "Family Bombyliidae- Bee Flies" (On-line). Bug Guide. Accessed August 09, 2013 at

Yela, J., C. Herrera. 1993. Seasonality and lifecycles of woody plant feeding noctuid moths (Lepidoptera, Noctuidae) in Mediterranian Habitats. Ecological Entomology, 18: 259-269.

University of Michigan Museum of ZoologyNational Science Foundation

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Sames, J. 2014. "Villa alternata" (On-line), Animal Diversity Web. Accessed April 17, 2024 at

BioKIDS is sponsored in part by the Interagency Education Research Initiative. It is a partnership of the University of Michigan School of Education, University of Michigan Museum of Zoology, and the Detroit Public Schools. This material is based upon work supported by the National Science Foundation under Grant DRL-0628151.
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