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Subject: What’s this bug?
Location: South Africa
December 4, 2014 10:46 pm
On a recent trip to a game reserve in South Africa (Pilanesburg), we stopped at a picnic area and came across these weird looking “flies”. They where large, being approximately 2 cm long and there where about 20 of them in one concentrated area. They where very lethargic and did not fly off when approached or even moved with a stick. They move slowly.
Signature: Regards, Sean

Buzzard Signal Fly

Buzzard Signal Fly

Dear Sean,
To say that we were taken aback when we first viewed your images is an understatement.  We could not even decide if this was a wasp or a fly.  The general shape of the body indicated to us that it is a fly, yet the head almost looked more like a wasp.  To further complicate matters, our first stop for South African identifications, iSpot, is currently doing a site migration and though we found images that looked similar, we were unable to read about those sightings on iSpot.
  We eventually located a posting on FlickR that identified this unusual fly as a Rooikopvlieg, Bromophila caffra.

Rooikopvlieg

Rooikopvlieg

Searching that scientific name lead us to Beetles in the Bush where a lengthy posting provided a common name of Buzzard Signal Fly.  According to Beetles in the Bush:  “It is a member of the family Platystomatidae, commonly known as signal flies and part of the great superfamily Tephritoidea of fruit fly fame (i.e., true fruit flies – not “the” fruit fly which belongs to the family Drosophilidae and which are more properly called vinegar flies). … But what about Bromophila caffra? Aside from being one of the most recognizable of flies in Africa, it’s sluggish disposition and apparent noxiousness were obvious even to early naturalists. Marshall (1902) noted the similarity of its coloration (black body, blue wings, red or yellow head) to that of two Pompilus spp. and one sphecid wasp with which it occurred sympatrically.”    In closing, Beetles in the Bush coins a heretofore lacking common name with this justification:  “I find it surprising that a large, strikingly distinctive, abundant insect such as Bromophila caffra should lack a common name, but it appears this is the case. None was given in Field Guide to Insects of South Africa, nor amongst the several South African wildlife and dipteran websites which I encountered featuring photos of this insect. In thinking about what common name Bromophila caffra could have, I can’t help but draw comparisons between this insect and the turkey vulture (Cathartes aura), or “buzzard,” of North America (despite their belonging to entirely separate phyla). Both species are among the larger members of their respective orders and make their living eating repulsive foodstuffs. Hulking black with naked, red, plastic-like heads, most predators regard them as too vile and noxious to bother with, leaving them free to pass their lives in unmolested disdain. With this in mind, I hereby propose ‘buzzard signal fly’ as the official common name for this insect.”

Buzzard Signal Fly

Buzzard Signal Fly

 

Linda Singleton, Amy Gosch, Andrea Leonard Drummond liked this post
What's That Bug? does not endorse extermination

What’s this fly?
December 27, 2009
Came across this handsome fella while staying at a chalet in the Taman Negara rainforest in Malaysia. It was hanging around some fruit I had on the table. Pix were shot yesterday. (Dec 27)
I’m pretty certain it is of genus Drosophila. Would you happen to know the species?
Chan Lee Meng
Kelantan, Malaysia

Unknown Fruit Fly

Signal Fly

Dear Chan Lee Meng,
We disagree with your assessment that this handsome fly is in the genus Drosophila, but we do believe it is a Fruit Fly in the family Tephritidae.  We do not feel qualified to take the identification any further than the family level, but perhaps one of our readers will be able to supply an answer.

Unknown Fruit Fly

Signal Fly

Update:  March 30, 2014
A comment has directed us to this link and the correction that this is a Signal Fly.

What's That Bug? does not endorse extermination

3 different flies with patterned wings
November 29, 2009
Here are 3 similar but different flies that were all sitting near each other. Two were perched on squash leaves in a vegetable garden. The very black one (in the last photo) was nearby on a wall near a sunflower. I took the photos on July 23rd and it was a warm sunny day. They were all smaller than the common housefly. And the black one was larger than the other two. They all look related but the wing patterns are different on each one. The 2nd pic fly is eating a bird (or teeny lizard) dropping. Could one (or more) of them be a walnut husk fly? Our neighbor has a walnut tree. Is it just a coincidence that they are hanging out together?
I aalso have photos of a green jumping spider protecting her eggs…I photograghed daily until the eggs hatched, little spiderets everywhere and mom had left. I don’t need any identification, just wondering if you’d like me to send some pics of the process.Thank you……
swarner
Fredericksburg, VA

Black Onion Fly

Black Onion Fly

Hi swarner,
We have been very busy recently, and today we are randomly selecting older letters to look for good postings.  Your photos are awesome.  We believe all three of your flies may be Picture Winged Flies in the family Ulidiidae, and we have conclusively identified the Black Onion Fly, Tritoxa flexa, on BugGuide.  The species if found over much of North America, and it is associated with cultivated garlic.

Picture Winged Fly

Picture Winged Fly

A second Picture Winged Fly is Delphinia picta, also found on BugGuide, and it breeds in compost piles.  The two white triangles on the leading edge of the wings is a distinguishing feature.

Signal Fly

Signal Fly

Continued searching revealed your final fly to be a Signal Fly in the genus Rivellia.  According to BugGuide, they are found on foliage feeding on feces, exactly as your photo depicts.

What's That Bug? does not endorse extermination