Hoverfly: All You Need to Know – A Quick Guide for Enthusiasts

Hoverflies, also known as flower flies or syrphid flies, are part of the insect family Syrphidae. These fascinating creatures are often mistaken for bees or wasps due to their color patterns, which mimic stinging insects as a form of protection from predators.

With their unique hovering flying pattern, hoverflies can be commonly found visiting flowers in gardens and other blooming environments. They play an important role as natural enemies of aphids, scale insects, and thrips, particularly during the larval stage of their life cycle.

In addition to being beneficial predators, hoverflies also contribute to pollination as they visit flowers to feed on nectar and pollen. While enjoying these food sources, hoverflies inadvertently transfer pollen between flowers, assisting with their fertilization and the overall health of plant populations.

Hoverfly Identification and Appearance

Hoverflies, also known as flower flies or syrphid flies, belong to the family Syrphidae. They are often mistaken for bees or wasps due to their similar appearance. However, there are a few key differences that make it easier to distinguish them.

These flies are usually 1/8 to 1 inch long, with a robust or slender body. Hoverflies have a distinct black body, featuring bands or stripes of orange, yellow, or white, resembling the patterns of stinging bees or wasps¹. Some species have a brown or metallic appearance as well².

While bees and wasps have two pairs of wings, hoverflies are part of the insect order Diptera, which means they have only one pair of wings³. Additionally, hoverflies have large eyes and distinct antennae, unlike bees and wasps⁴.

Some examples of common hoverflies include the Scaeva pyrastri and the Episyrphus balteatus⁵.

A simple comparison table to help identify hoverflies:

Hoverfly Life Cycle and Reproduction

Eggs

Hoverflies lay their eggs near aphid colonies, as their larvae feed on aphids. The eggs are usually white or light brown and are laid on the undersides of leaves or other surfaces close to the aphid colonies. Some examples of plants where hoverflies lay their eggs include:

• Milkweed
• Yarrow
• Goldenrod

Larvae and Maggots

Once the eggs hatch, the larvae, also referred to as maggots, immediately start feeding on aphids and other small insects. The hoverfly larvae have a tapered, legless, maggot-like appearance and are usually green, brown, or cream-colored. Some key features of hoverfly larvae include:

• Aphid consumption: Each larva can consume hundreds of aphids during its development
• Camouflage: Larvae blend in with their surroundings to avoid predators

Pupa

After consuming enough aphids, the hoverfly larvae pupate and undergo metamorphosis. The pupa is typically brown and can be found in the soil or on leaf surfaces. During this stage, the hoverfly does not feed and remains motionless until it emerges as an adult.

Adult Hoverflies

Adult hoverflies, also known as syrphid flies or flower flies, are often mistaken for bees due to their black and yellow stripes. They play an essential role in pollination and pest control.

Distinct characteristics of adult hoverflies:

• One pair of wings: Unlike bees, hoverflies have only one pair of wings
• Size: They vary in size from 1/8 to 1 inch long
• Mating: Adult hoverflies mate to lay eggs and continue the life cycle

In conclusion, the hoverfly life cycle includes four stages: eggs, larvae/maggots, pupa, and adult hoverflies. These beneficial insects play a vital role in pollination and maintaining a balanced ecosystem by controlling aphid populations.

Role in the Ecosystem

Hoverflies play important roles in various ecosystems, providing ecological services such as pollination and pest control.

Pollination and Plant Benefits

Hoverflies are efficient pollinators because they visit numerous flowers to consume nectar and gather pollen. By doing so, they contribute to plant reproduction and ensure gardens thrive with diverse flora. Some benefits of hoverfly pollination include:

• Improved yield in fruits and vegetables
• Enhanced biodiversity in plants
• Supporting the lifecycle of other beneficial insects

For example, hoverflies are known to pollinate a wide range of flowers, contributing to the overall health of the ecosystem.

Natural Pest Control

In addition to pollination, hoverflies also serve as natural pest controllers, mainly in their larval stage. Hoverfly larvae consume common garden pests like aphids, helping maintain balance within ecosystems. They are considered valuable natural controls and contribute to population regulation of aphids.

Examples of this pest control can be seen in crops like lettuce, where hoverfly larvae help protect the plants from damage caused by aphids. Some practices enhance hoverfly populations, like planting nectar-producing plants that hoverflies prefer, resulting in better pest control for nearby fields.

Predators and Prey

Hoverflies, like other insects in ecosystems, have their own predators and prey.

Predators:

• Birds
• Spiders
• Other predatory insects

Prey:

• Aphids (by hoverfly larvae)
• Pollen and nectar (by adult hoverflies)

Overall, hoverflies are an essential part of the ecosystem, providing pollination, plant benefits, natural pest control, and contributing to the intricate web of predators and prey. By understanding their role, we can appreciate their impact on our gardens, crops, and the environment.

Hoverfly Distribution and Habitat

Hoverflies, also known as flower flies or syrphid flies, are a diverse group of important pollinators and natural enemies of various pests. They can be found in many regions around the world, inhabiting various ecosystems.

These flies are often spotted around flowers due to their preference for nectar and pollen as food sources, giving them the nickname “flower flies.” They can be found in gardens, orchards, and other places with abundant nectar-producing plants.

Some common species of hoverflies, such as the Scaeva pyrastri, are known to inhabit the Pacific Northwest region and can be found in orchards.

Hoverflies are generally found in areas with:

• Abundant flowers
• Suitable habitats for their larvae
• Availability of prey, such as aphids and scale insects

In order to support hoverfly populations, conservation efforts may focus on providing nectar-producing plants like alyssum. This encourages hoverflies to inhabit areas adjacent to crop fields, benefiting both the pollination process and pest control efforts.

Interaction with Humans and Animals

Hoverflies are known to be beneficial insects, providing several advantages to humans and the ecosystem. Their role as pollinators [7-10] and larvae being biocontrol agents of aphid crop pests [11] demonstrates their value (source).

Adult hoverflies feed on nectar in flowers, while their larvae are voracious predators of aphids. This dual function makes them indispensable to the agricultural sector and a natural pest control method (source).

Their appearance resembles bees or wasps, a clever form of mimicry that potentially protects them from predators (source).

For a clearer understanding, here’s a table highlighting key differences between hoverflies, bees, and wasps:

Considering their interaction with humans and nature, some key points about hoverflies are:

• Play a vital role as pollinators and pest control agents
• Mimic bees and wasps for protection
• Are integral to maintaining ecological balance
• Positively impact agriculture and gardening

In summary, hoverflies play a significant role in both human and natural ecosystems. Their ability to pollinate and control aphid populations ensure that they remain an essential link in our environment.

Hoverfly Pests and Diseases

Hoverflies, also known as flower flies and syrphid flies, are beneficial insects in gardens and agricultural fields. They are natural enemies of aphids and other small, slow-moving insects. They are often confused with bees or wasps due to their similar appearance, but they are harmless.

Adult hoverflies mainly feed on nectar and pollen, while the larval stage is predaceous, feeding on pests like aphids, scale insects, and thrips. A healthy population of hoverflies can significantly reduce pest populations.

Pests

• Aphids
• Scale Insects
• Thrips ()

In general, hoverflies themselves are not associated with any specific pests or diseases. However, they can be affected by common insect predators such as:

• Parasitic Wasps
• Predaceous Beetles
• Spiders

Diseases
Few diseases affect hoverflies, but they can sometimes be subject to fungal or viral infections, like many other insects.

Pros and Cons

Pros

• Natural pest control
• Increase pollination
• Attractive appearance

Cons

• Can be mistaken for stinging insects
• Require proper management to maintain populations

In the table below, hoverflies are compared to another natural predator, ladybeetles:

Managing hoverfly populations can be as simple as providing flowers rich in nectar and pollen for the adults, attracting more hoverflies to your garden and helping maintain a natural balance of beneficial insects.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Corn Tassle Fly is actually Hover Fly, but which species????? Toxomerus politus

Subject: Corn Tassel Fly
August 4, 2014 8:58 pm
I have a picture of said insect (That is what we in Indiana call them too…corn fly or corn tassel fly) and would like to contribute to your information.
Signature: Chawn Essary

please use the Ask What’s That Bug? link on our site and use Corn Tassel Fly as the subject line.

I have tried 3 times to submit that way and it just keep processing and never finishes? (the little arrow went around so much, I think I got dizzy! LOL)
So, here you go “Bug Man”!!
Thanks for your awesome site!
Best Regards,
Chawn

Hi Chawn,
Though your images are enormous, our email program should have handled 12M worth of attachments.  Perhaps your internet connection was slow.  Do you generally have problem emailing such large attachments?  More that ten years ago, we received an identification request from Illinois with no images that described a Corn-Tossle Fly, and based on the description, we decided it was a Flower Fly, also called a Hover Fly, from the family Syrphidae.  The common name Flower Fly refers to their pollinating behavior and the name Hover Fly refers to their ability to fly in place.  Your images confirm that identification.  Interestingly, we cannot find any other references to that name, but we must confess we only did a quick and superficial search for the term.  Flies in the family Syrphidae are highly beneficial.  The adults help to pollinate plants and the larvae feed on garden pests including aphids.  Alas, we could not locate an exact match to your Corn Tassle Fly on BugGuide, however, we suspect that based on its physical appearance, your individual is in the subfamily Syrphinae, and perhaps you will have better luck navigating BugGuide to a species identification than we had.  It is also worth noting that many flies in the family Syrphidae mimic bees or wasps, and since the Hover Flies are perfectly harmless, this affords them some protection.  We have greatly enlarged the Hover Fly and cropped tightly in the hope that one of our readers will be able to identify the species, or at least the genus for us.

Update:  August 17, 2014
Thanks to Kevin Moran who wrote in identifying the Corn Tassle Fly as Toxomerus politus which we located on BugGuide, though the common name is not indicated.  Kevin also provided a link to this pdf http://syrphidae.lifedesks.org/pages/25598/pdf  that provides this information:  “The larvae of Toxomerus politus (Say, 1823) also known as ‘the corn-feeding syrphid fly’, feed on pollen and sap from the saccharine cells of corn (Zea mays L.) (Marín A.1969; Smith 1974)”

Letter 2 – Flower Flies

Subject:  what’s this bug?
Geographic location of the bug:  Houston, Texas.
Date: 11/08/2017
Time: 10:53 AM EDT
They love flower juice.
How you want your letter signed:  Tan Doan

Dear Tan,
These are Flower Flies or Hover Flies in the family Syrphidae.  Many members of the family mimic bees and wasps to help deter predators.  Adults are beneficial pollinators and larvae eat Aphids and other small detrimental insects found on plants.

Letter 3 – Immature Flies may be Hover Fly larvae

Subject: Bug found in bedroom
Location: Swingfield Street, Kent
October 15, 2014 4:45 am
Found several of these bugs on the carpet in the bedroom on returning from a week or so away from the house.
What are they?
Signature: Anthony

As you can not tell from the pictures, I should have said that it is soft and moves a bit like a caterpillar and that the dark portion is at the tail end not the head.
I had a video that showed the above but it was rather big so I did not send it.
I am attaching the photos again in case it is difficult to tie up the 2 emails.
Regards,
Anthony.

Dear Anthony,
We are unable to provide anything more than a very general identification at this time.  This is an immature Dipteran, the insect order that includes Flies.  They remind us of the larvae of a Bot Fly, but we cannot be certain.  See this posting on BugGuide.

Letter 4 – Probably Hover Fly from New Zealand

Subject: Bee or fly

Location: New Zealand
January 27, 2017 7:02 pm
Hi Bugman… can you identify this bug for me. The closest I can find is that it is a NZ Hoverfly, I have never seen one before so I am very interested in finding out the information you have about it. It was flying around inside yesterday (28.01/17) It is suppose to be summer here in New Zealand, but the weather here is very spring like. Yes I took the photo myself in our lounge. I hope it is clear enough.
Thank you
Signature: Ngaire Faull

Dear Ngaire,
Flies have one pair of wings while most other insects, including bees, have two pairs of wings.  Your insect appears to be a fly, judging by its shape and what we are able to make out of the antennae, but there is not enough detail in your image to be certain.

Thanks Daniel.. what sort of fly? Did you see the one yellow stripe and that long stinging looking thing off its behind?

We agree with comments provided by Cesar Crash that this is probably a Hover Fly