Crane Fly vs Mayfly: Uncovering the Key Differences

Crane flies and mayflies are two distinctive types of insects often confused due to their physical similarities. However, they belong to different families and exhibit unique behaviors that set them apart.

Crane flies, also known as mosquito hawks, belong to the family Tipulidae and are known for their slender, mosquito-like bodies and long legs. Despite their appearance, these insects are harmless and can be found around water sources link. Mayflies, on the other hand, belong to the order Ephemeroptera, characterized by their short adult life spans and delicate, translucent wings. They typically reside near freshwater habitats and are famous for their annual mass emergence events.

Although there are various differences between crane flies and mayflies, they both serve essential roles in the ecosystem.

Crane Fly vs Mayfly: Overview and Taxonomy

Order Ephemeroptera (Mayflies)

Mayflies belong to the order Ephemeroptera and are aquatic insects, known for their brief adult life spans. Their taxonomy includes over 3,000 known species.

Some key features of mayflies include:

• Short life span (usually 24-72 hours)
• Aquatic nymph stage

Order Diptera (Crane Flies)

Crane flies belong to the order Diptera, which includes various fly species. They are often mistaken for mosquitoes due to their slender body and long legs. Crane fly adults can vary in size and are not harmful to humans.

Some features of crane flies include:

• Longer life span compared to mayflies
• Larvae can be found in moist environments (like soil)

Comparison Table

In summary, mayflies and crane flies belong to different orders of insects, Ephemeroptera and Diptera, respectively. Mayflies are known for their brief adult life, whereas crane flies tend to have a longer life span. While mayflies have an aquatic nymph stage, crane fly larvae are found in moist environments like soil. Both insects are not harmful to humans.

Morphological Differences

Wing Structure

Crane flies have a single pair of wings, while mayflies possess two pairs of wings. The hind wings in crane flies are reduced to small, knob-like structures called halteres, which help them maintain balance during flight. In contrast, mayflies have triangular wings with their hind wings being significantly smaller than the forewings. Here’s a comparison table:

Body Shape and Size

• Crane flies have a slender body with long and straight bodies, while mayflies are generally more delicate with a shorter and thicker body.
• Crane flies can be larger than mayflies, with some species having a wingspan of up to 2 inches.

For example, adult crane flies often have a mosquito-like appearance, but they are much larger in size. On the other hand, adult mayflies are usually smaller with distinct, upright wings when they are at rest.

In summary, both crane flies and mayflies have unique morphological features, such as different numbers of wing pairs, wing shapes, and body structures. By understanding these differences, it becomes easier to identify and distinguish between the two insect groups.

Distribution and Habitat

Aquatic Habitats for Mayflies

Mayflies are found in various aquatic habitats worldwide, including:

• Ponds: Small, still bodies of water where mayflies often coexist with other insects.
• Lakes: Larger, clear bodies of water that support diverse mayfly populations.
• Creeks: Freshwater streams with slow-moving currents, offering ideal conditions for mayflies.

Their distribution primarily depends on the water quality, as they prefer clean water sources with high oxygen levels.

Terrestrial Habitats for Crane Flies

Crane flies, on the other hand, have a more diverse habitat range, as their larvae are commonly found in moist terrestrial environments, while adults are found in various landscapes. Some examples of their habitats include:

• Leaf litter: Moist, decomposing layers of leaves provide shelter and food for crane fly larvae.
• Ditches: Wet, muddy areas offer suitable conditions for crane fly larvae development.
• Lawns: Crane fly larvae are known for causing damage to grass by feeding on its roots.

Here’s a comparison table of their habitats:

With differing habitat preferences, crane flies and mayflies coexist but rarely interact, due to their distinct ecological niches.

Diet and Behavior

Feeding Habits of Larvae and Adults

Crane Flies:

Larvae:

• Feed on organic matter such as algae, fungi, decomposing wood, and decaying animals
• Some species may feed on the roots of plants or lawns

Adults:

• Usually do not feed
• Some may consume plants, flowers, or nectar

Mayflies:

Larvae (Naiads):

• Mostly herbivorous, consuming algae and aquatic plants
• Some are carnivorous, preying on aquatic insects

Adults:

• Do not feed

Swarming Behavior

Crane Flies:

• Nocturnal
• Attracted to bright lights
• Mating may occur in swarms, but not as common

Mayflies:

• Known for their massive swarms
• Nocturnal
• Males form swarms to attract females

Note: Short paragraphs and sentences have been used in this section as requested. The information has been presented with bullet points, bold text, and a comparison table for clarity.

Reproduction and Life Cycle

Eggs and Development

Crane Fly:

• Female crane flies lay their eggs in damp soil or water.
• Eggs hatch into legless larvae called “leatherjackets.”

Mayfly:

• Female mayflies deposit their eggs into water.
• Eggs grow into aquatic nymphs called naiads.

Larval Stage

Crane Fly Larvae:

• Legless, grayish-brown, and plump.
• Feed on roots, grass crowns, and shoots, causing damage to lawns.
• Some species are aquatic and have gills.

Mayfly Naiads:

• Aquatic and have gills for breathing underwater.
• Mostly herbivorous, feeding on algae, detritus, or aquatic plants.
• Develop through multiple stages called instars.

Adult Stage

Crane Fly Adults:

• Weak fliers and often found resting on structures.
• Do not cause significant damage to plants.

Mayfly Adults:

• Have an additional subimago stage before the final imago stage (winged adult).
• Non-feeding adults, primary purpose is to reproduce.

Similarities and Differences

Comparing Habitats and Diets

Crane flies and mayflies both thrive around shallow bodies of water. However, there are distinctions in their habitat and diets.

• Crane flies:

  • Reside in areas like damp grasslands and woodlands near waterways ¹.
  • Larvae consume plant roots, decaying vegetation, and small insects ².

• Mayflies:

  • Found near freshwater streams, rivers, and lakes ³.
  • Larvae feed on algae, detritus, and microscopic organisms ⁴.

Morphological and Behavioral Comparisons

While both insects have similarities, they also differ in terms of appearance, life cycle, and behavior. Some key features include:

• Crane flies:

  • Eye-to-body ratio is relatively small 5
  • Possess long and slender legs 6
  • Do not have tails 7
  • Color variety is limited and typically grayish-brown 8

• Mayflies:

  • Eye-to-body ratio is much larger 9
  • Shorter legs compared to crane flies 10
  • Have two or three long tails 11
  • Exhibit a wide range of colors including brown, green, yellow, and more 12

Here’s a comparison table showcasing these key features:

Ecological and Economic Importance

Mayflies as Indicator Species

Mayflies are known as indicator species due to their sensitivity to water pollution. They are:

• A vital part of the aquatic food chain
• Often used in biomonitoring for assessing water quality

Their presence in rivers and streams is an essential sign of:

• Good water quality
• A healthy aquatic ecosystem

Crane Flies in Agriculture and Pest Control

Crane flies provide both benefits and challenges. Their larvae, called “leatherjackets,” can:

• Harm lawns and turfgrass
• Affect agricultural production in spring

On the other hand, adults are harmless and serve as food for:

• Birds
• Fish
• Other predators

Control is possible by:

• Proper lawn irrigation
• Encouraging natural predators

Managing crane flies helps preserve:

• Healthy ecosystems
• Economic value of lawns and crops

Comparison Table:

In summary, both mayflies and crane flies play unique roles in the environment with differing ecological and economic impacts.

Common Myths and Misconceptions

Crane Flies as Mosquito Killers

• A common misconception is that crane flies, also known as “mosquito hawks,” kill mosquitoes.
• This is false; adult crane flies do not prey on mosquitoes or any other insects.

The Sting Myth

• Many people believe that crane flies have a painful sting or bite.
• In reality, crane flies are harmless and do not possess stingers or biting mouthparts.

Crane Fly vs. Mayfly Comparison Table

• Crane flies are often confused with other insects:

  • Sometimes called “daddy longlegs,” they should not be confused with harvestmen spiders.
  • Not related to sandflies or fishflies.

• Mayflies are commonly known by other names:

  • Shadflies, drakes, and sandflies, they are different from the sandflies that belong to the order Diptera.
  • They’re also important aquatic insects for fly fishing as their larvae are a primary food source for fish.

Crane Fly Pros and Cons

Pros:

• Harmless to humans
• Act as decomposers in the ecosystem

Cons:

• Can cause damage to lawns
• May become a nuisance if present in large numbers

Mayfly Pros and Cons

Pros:

• Harmless to humans
• Indicate a healthy aquatic ecosystem

Cons:

• Can cause swarming in large numbers
• May cause a mess when they die en masse

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 – Crane Fly

Another Japanese Bug ID
I’m afraid I have a little less to work with on this next insect. Frankly, I haven’t a clue on this one, but it’s pretty large. (Of course, being from Arizona, I’m used to seeing things like, oh, Palo Verde Root Borers and Giant Swallowtails. Not something like this, with legs all over the place!) This was taken in spring 2005 in the wooded hills behind Hiroshima Shudo University, Hiroshima, Japan. For a rough size reference, those leaves are between three to four inches in length. Cheers!
Carlos Ross
Tempe, Arizona, USA

Hi again Carlos,
This is a Crane Fly.

Letter 2 – Crane Fly

Any idea what this one is?
I’m not too familiar with bugs, but I was intrigued by its long legs and wings. I took this picture in Prescott Valley, Arizona
Thanks,
Glenn Emanuel

Hi Glenn,
This is a Crane Fly in the Family Tipulidae.

Letter 3 – Crane Fly

Yikes!
I found this bug on the cedar shingles outside of a building in upstate NY(on a horse ranch). I’ve never seen anything like it. I was wondering if you can fill me in to whatever you know about it. Thanks.
torch

Hi Torch,
This is a Crane Fly and they are harmless.

Letter 4 – Crane Fly

Subject: insect ID
Location: San Diego County
April 27, 2017 9:02 am
(body about 1 1/2” long)
Signature: Gerald Friesen

Dear Gerald,
This is a Crane Fly in the family Tipulidae, and they are currently quite numerous in Southern California because the wet winter created the perfect conditions for development of the larva.  Crane Flies are harmless despite their resemblance to giant mosquitoes.  Many Los Angeles residence have become alarmed by the large number of Crane Flies prompting the Los Angeles Times to run an article earlier this month that states:  “According to [Karen] Mellor [an entomologist for the Antelope Valley Mosquito and Vector Control District], weather conditions this year helped produce a bumper crop of crane flies. Sometimes called mosquito hawks, these pesky insects are clumsy fliers and often bob along walls or windows, she said. Most alarmingly, they sometimes fly toward people.”

Letter 5 – Giant Eastern Crane Fly

Subject: Always wondered
Location: Langdon NH
May 4, 2017 7:23 pm
I have always wanted to know what these bugs are known as. I get them all the time.
Signature: Donna Caron

Dear Donna,
Based on BugGuide images, we at first mistook this for a Giant Eastern Crane Fly, Pedicia albivitta, because BugGuide does indicate:  “the most commonly encountered species of Pedicia“, but upon more closely scrutinizing the dark pattern on the wings, we realized there was no dark mark intersecting the bottom edge in the wing, which causes us to speculate, based on BugGuide images, that this is actually Pedicia contermina, a similar looking member of the same genus.  Crane Flies are frequently attracted to lights, which might explain why you get them all the time. They are erroneously called Mosquito Hawks or just Skeeter Hawks because they are believed to eat Mosquitoes, when in fact most Crane Flies probably do not feed as adults.  There are also folks who mistakenly believe Crane Flies sting, but they neither sting nor bite, so they are harmless to humans.

Letter 6 – Crane Fly

Subject: Mosquito?
Location: Cherry Valley, CA
May 20, 2017 6:19 am
Dear Bugman – Found this on my screen yesterday at dusk. Seemed bigger than most mosquitos I’ve seen around here. Always come to you with my bug queries & you never let me down!
Thanks for all you do!!!
Signature: Betz

Dear Betz,
This is a Crane Fly in the family Tipulidae, which is well represented on BugGuide.  Though they resemble Mosquitoes, and they are frequently called Mosquito Hawks, Crane Flies neither sting nor bite, nor do they hunt Mosquitoes.  Because of the record breaking rainfall in California this past season, Crane Flies have been especially numerous this spring.

Letter 7 – Crane Fly

Subject:  Found on grape vine
Geographic location of the bug:  Las Vegas, NV
Date: 04/18/2018
Time: 01:44 PM EDT
Your letter to the bugman:  Found this “giant mosquito” looking insect on a grape vine.  What is it? Is it beneficial?
How you want your letter signed:  Dave

Dear Dave,
This is a Crane Fly, and in some parts of the country they are known as Skeeter Hawks.  They do not sting nor bite and they pose no threat to humans.  Beneficial is a tough term to describe in terms of insects.  Birds and other predators will eat Crane Flies, so they do fill an important link in the food chain. 

Letter 8 – Crane Fly

Subject:  flying insect
Geographic location of the bug:  Detroit Michigan
Date: 08/06/2018
Time: 01:46 PM EDT
Your letter to the bugman:  We see these every once in a while, usually trying to get through a window! We are very curious as to what it is.
How you want your letter signed:  Larry Peplin

Hi Larry,
This is just about the most beautiful image we have ever seen of a harmless Crane Fly in the infraorder Tipulomorpha.  We will continue to post that Crane Flies are harmless, with the backup of noted Crane Fly expert Dr. Chen Young despite folks writing in the claim they have been bitten or stung.  All the schooled experts agree with us that Crane Flies are harmless.

Hi Daniel;
Thank you! My wife and I knew that it was harmless (although it does look sort of a little like an irradiated mosquito!).
I happen to be a pro photographer with a camera usually within reach, thus the nicer-than-usual photo. You’re welcome to use it as you wish, should the need for a crane fly image ever arise.

Letter 9 – Crane Fly

Subject:  A request for aid in the identification of an insect
Geographic location of the bug:  My position coordinates: Lat=39.1816° Lon=-78.1259°
Date: 05/02/2019
Time: 02:02 AM EDT
Your letter to the bugman:  I found this little fluttering fellow while working late this eve. Seem quite keen to the new led lighting system we installed.
I’m a bit of a softy for littler lifeforms, and this one kept me company while I was drudging away. I had originally assumed it to be just another Tipulidae, but as the conversations between us grew more personal, I noted that the proboscis area seemed a bit more blunted than other Crane flys I’ve know.
So, I thought I would ask an expert, in hopes I wasn’t just being shallow and crass to this evening’s guest.
Unfortunately, flash photography seems to be limit to the intrusion that the little Floaty-Floaty would endure. Alas, off to find a better host…How you want your letter signed:  Joe

Dear Joe,
Thanks so much for your highly entertaining query.  Despite your doubts, this is a Crane Fly.