Currently viewing the category: "Cactus Flies"
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Subject: What bugs are these?
Location: Cairns, QLD, Australia
December 3, 2016 7:11 am
Found these in my yard.
Signature: CE

Stilt Legged Fly

Stilt Legged Fly

Dear CE,
Like another of your submitted images, we believe this is a Stilt Legged Fly in the family Micropezidae, but unlike the previous image, we have not been successful in finding any matching images from Australia online.  We are postdating this submission to go live to our site when we are out of the office for the holidays at the end of the month.

Correction Courtesy of Karl:  Banana Stalk Fly
Hi Daniel and CE:
This is actually a Banana Stalk Fly (Family Neriidae); we usually call them Cactus Flies in North America. Depending on which source you read, there are either two or three species in Australia. Of these, I believe Telostylinus lineolatus is the closest match. Regards, Karl

Thanks so much Karl.  Interestingly, we have a mating pair of Banana Stalk Flies from Hawaii in our archives, and that posting is also listed as Stilt Legged Flies.  We will create a Cactus Fly subcategory for both postings.

What's That Bug? does not endorse extermination

Special Mosquitos?
Location: Palolo Valley, Honolulu, HI
December 16, 2010 5:39 pm
Found these two getting busy on the shoe rack this morning… I hope they don’t recognize and remember faces for an attack later on when they’re done… Are these special mosquitoes or something? They sure don’t look like a regular Mosquito!
Signature: TH

Mating Banana Stalk Flies

Dear TH,
Wow, what an awesome photo you have sent to us.  We have no idea where to begin researching the identity of these unusual looking mating Flies, but we can assure you that they are not mosquitoes.  Like so many other creatures in Hawaii, we suspect these might be an introduced species, possibly from Asia.

Immediate Update
We quickly found a match for your mating Flies.  They are identified on BugGuide as Banana Stalk Flies, Telostylinus lineolatus, in the family Neriidae, the Stilt Legged FliesThe Cook Islands Biodiversity website has a page devoted to the Banana Stalk Fly, and they list the other common names Banana Fly, Push-me-Pull-me Fly and Push-pull Fly.  The range is listed as “Sri Lanka – Indonesia / Australia – Marquesas, Hawai‘i” and it is considered a pest species, but the site does not indicate why.  The Rainforest Revelations website has this information:  “With enormous eyes, this tiny, tropical, stilt-legged fly maintains a confident distance from human approach, by swiftly running around the blind-side of whatever surface it is on.  … Telostylinus lineolatus inhabits tropical north Queensland, where it aggregates on flowers and rotting fruit.  They are members of Neriidae, which is a relatively small family of true flies (Diptera) with long, stilt-like legs.”  The Evolutionary Biology Lab Research website has this information on the family:  “Neriidae is a relatively small family of true flies (Diptera) with long, stilt-like legs. Most species are found in the tropics. Neriids have very interesting behaviours, and many species are strikingly sexually dimorphic, with males having much longer legs, heads and/or antennae than females. Like piophilid flies, neriid larvae have the ability to leap during the stage just before pupation when they migrate from the larval feeding substrate to the pupation site. Very little research has been done on this interesting group of flies.

Correction January 2, 2017
Though we correctly identified the species, we now know that Banana Stalk Flies are in the Cactus Fly family Neriidae.

What's That Bug? does not endorse extermination