# Phorid flies ..truly dangerous?



## infinitebohr (Feb 19, 2012)

Hello all!

Spent some time reading past posts about phorid flies since I believe I have these in my invert room. After reading many posts, checking other forums, and reading in several books (T Keeper's Guide for one), I can honestly say I'm not totally convinced about the Phorid fly threat. Don't get me wrong, I am certainly not an expert and I'm not trying to be a contrarion just to troll the forums or the commonly held belief. However almost everything I read was speculative and usually just a story about a T dying, Phorids being sited in the area and the conclusion being drawn that the phorids must have done it! I know that we all lose invertebrates unexpectedly and often times without an explanation. I posted recently about a very strange brown spot appearing on my vinegaroon, and I haven't seen him for almost a week now...so I'm expecting the worst, but at this point I just don't feel that the probability lies in the direction of the phorids. 

My point is that I was unable to find hard evidence that phorid flies do in fact parasitize tarantulas, scorpions, crabs, or pedes. I did find (as noted in other posts) that a particular species is infamous for fire ant control, but not much else. Almost everything listed them as a scavenger of decomposing materials, fungi, and that they show a special love of dead crickets. A few people mentioned them as a vector for nematodes, and that certainly is a scary notion! 

It certainly could be that I'm simply in denial about them, or maybe I'm just flat wrong. I just wanted to see if anyone could 100% lay this to bed? I didn't find a post that gave conclusive evidence. The authors of T keeper's guide seem to believe in this problem, and that certainly gives me pause, but I just can't shake the thought that if the maggots (or flies) really do crawl inside the T's mouth or what have you, I feel this would have been widely documented and would be a well known phenomenon rather than a "well this happened once to us" kind of thing.

Thanks in advance for any thoughts and please remember this was written out of curiosity and healthy skepticism! (and hopefully not too much ignorance) I look forward to finding out whether I just have an annoying pest problem, or an entire collection to quarentine and rehouse :cry:


----------



## Formerphobe (Feb 19, 2012)

> vector for nematodes


From my reading, this is the biggest concern.


----------



## BenjaminBoa (Feb 20, 2012)

I don't know much about phorid flies, I've had them in my Avic tank (they used to come from the pipes in our basement) I never had any issues, just changed the bedding and put in a water bottle upside down, with a funnel going into it (facing up) with a low powered light behind the bottom of the bottle. The flies go in and are too stupid to find their way out, even when the light is turned off. putting some fly paper along the rim of the screen catches them too, however a complete clean up always took care of them. If I had to guess I'd assume they're like the mold scare people have, where the mold wont cause the death of the Tarantula, but the fact that the mold is thriving is a signal of larger issues.

If I understand correctly, the phorid flies are scavengers of decaying organics, so are mites, fungi, mold, and many other things we find in our tanks. If phorid flies are thriving that means mites might be thriving that also means there is probably too much decaying organics inside the tarantula tank and things need to change. I'm pretty sure they're similar to mites in treatment too, I have gotten them in my plants a lot. It seems like they can't survive in soil that is dry (unless they've found a way to get into the moist decaying parts of roots or stems) My jade and my cactus never get them, unless there are fleshy parts that have died, however my pathos, spider plant, orchids, and shifflera get them all the time. I've found that putting in some traps, drying the plants out, pruning dead roots and leaves, and sometimes putting the plant in an air tight container for a few weeks takes care of them. If the flys still show up after all of that I jsut change the bedding (outside so no flies take off into my house.) And I make sure to use dry soil so any larva on the plant wont have an easy time maturing. My orchids, cactus, and Jade I will leave soiless for a week or so to make sure they're all gone. If I still can't get rid of them I throw the plant away, but I've only had to do that once.

Reactions: Like 1


----------



## Moonbug (Feb 20, 2012)

I guess it is the fire ants that need to beware.  They turn them into "zombies"!  I am not sure how or if the affect the tarantulas.  

http://news.nationalgeographic.com/news/2009/05/photogalleries/zombie-ants/


----------



## infinitebohr (Feb 20, 2012)

I find the correlation between the plants and the flies interesting. I use Pothos in almost every tank if it's moist enough...I wonder if that is the source of the flies! I am pretty good about picking up after my bugs and even though I've looked I've never seen maggot at all. The plants could be the answer...if that's the case, then out they go!


----------



## BenjaminBoa (Feb 21, 2012)

infinitebohr said:


> I find the correlation between the plants and the flies interesting. I use Pothos in almost every tank if it's moist enough...I wonder if that is the source of the flies! I am pretty good about picking up after my bugs and even though I've looked I've never seen maggot at all. The plants could be the answer...if that's the case, then out they go!


Just don't root the plant in the tank. If you cut one of the pothos vines and remove the leaves from a node or two above the cut and shove it into the soil it will root its self in no time, if it's not doing so hot just root it in a cup of water and then put it in your tank. That way you don't risk tracking any larva or mites in from the old potting soil or roots.


----------



## AbraxasComplex (Feb 21, 2012)

BenjaminBoa said:


> I don't know much about phorid flies, I've had them in my Avic tank (they used to come from the pipes in our basement) I never had any issues, just changed the bedding and put in a water bottle upside down, with a funnel going into it (facing up) with a low powered light behind the bottom of the bottle. The flies go in and are too stupid to find their way out, even when the light is turned off. putting some fly paper along the rim of the screen catches them too, however a complete clean up always took care of them. If I had to guess I'd assume they're like the mold scare people have, where the mold wont cause the death of the Tarantula, but the fact that the mold is thriving is a signal of larger issues.
> 
> If I understand correctly, the phorid flies are scavengers of decaying organics, so are mites, fungi, mold, and many other things we find in our tanks. If phorid flies are thriving that means mites might be thriving that also means there is probably too much decaying organics inside the tarantula tank and things need to change. I'm pretty sure they're similar to mites in treatment too, I have gotten them in my plants a lot. It seems like they can't survive in soil that is dry (unless they've found a way to get into the moist decaying parts of roots or stems) My jade and my cactus never get them, unless there are fleshy parts that have died, however my pathos, spider plant, orchids, and shifflera get them all the time. I've found that putting in some traps, drying the plants out, pruning dead roots and leaves, and sometimes putting the plant in an air tight container for a few weeks takes care of them. If the flys still show up after all of that I jsut change the bedding (outside so no flies take off into my house.) And I make sure to use dry soil so any larva on the plant wont have an easy time maturing. My orchids, cactus, and Jade I will leave soiless for a week or so to make sure they're all gone. If I still can't get rid of them I throw the plant away, but I've only had to do that once.


It sounds like what you have is just fungus gnats. They are notorious for living in the soil of tropical plants. Harmless to your tarantula, but can cause issues for some plants if they begin to feed off of roots and stems. 

The majority of Phorid flies on the other hand need a source of decaying animal matter to lay their eggs and reproduce. I had a pair that lived on one of my Pamphobeteus sp. Chicken Spider for some time with no problems. I removed them over time, but there were no issues with her. The female only crawled off to lay eggs in dead crickets.

In another case one of my feeder colonies began to crash at the same time a massive phorid fly population exploded. Tiny maggots everywhere in the feeder bin, even on dying adults. I cleaned it out, decreased the humidity, and the feeders stopped dying with no more flies surviving. Were they killing the feeders? No clue, it could have been the humid substrate containing too much ammonia. The problem stopped when the quality of my husbandry increased.

Reactions: Like 1 | Informative 1


----------



## infinitebohr (Feb 22, 2012)

Yes, I've also considered the fungus gnats. I have this "moonlight" I leave on for ambient light for my inverts at night and they flies that fly to it always get stuck and die (it's extremely hot). I can try to snap a close up photo of one of the flies tomorrow. I'm pretty sure I'm seeing that distinct humpbacked shape though and my understanding is that this is the main characteristic to look for to identify phorids.


----------



## AbraxasComplex (Feb 22, 2012)

I've dealt with both and always have fungus gnats (though a bit of fly paper knocks the population down right away). It's easiest to identify them with a side by side photo (from various online sources) and a magnifying glass.

Reactions: Like 1


----------



## infinitebohr (Mar 3, 2012)

AbraxasComplex said:


> I've dealt with both and always have fungus gnats (though a bit of fly paper knocks the population down right away). It's easiest to identify them with a side by side photo (from various online sources) and a magnifying glass.


100% correct on the Fungus Gnat hypothesis. I took them down to my girlfriends research lab and we looked at them under the microscope. Big relief to find out they are just annoying pests rather than potential parasites.


----------



## BenjaminBoa (Mar 4, 2012)

AbraxasComplex said:


> It sounds like what you have is just fungus gnats. They are notorious for living in the soil of tropical plants. Harmless to your tarantula, but can cause issues for some plants if they begin to feed off of roots and stems.
> 
> The majority of Phorid flies on the other hand need a source of decaying animal matter to lay their eggs and reproduce. I had a pair that lived on one of my Pamphobeteus sp. Chicken Spider for some time with no problems. I removed them over time, but there were no issues with her. The female only crawled off to lay eggs in dead crickets.
> 
> In another case one of my feeder colonies began to crash at the same time a massive phorid fly population exploded. Tiny maggots everywhere in the feeder bin, even on dying adults. I cleaned it out, decreased the humidity, and the feeders stopped dying with no more flies surviving. Were they killing the feeders? No clue, it could have been the humid substrate containing too much ammonia. The problem stopped when the quality of my husbandry increased.


Huh, well that is good to know. What is the big difference between fungus gnats and phorid flies body wise? The guys I'm talking about have a little hunch to their back and almost look like black fruitfly- sized wasps, with a pointed ovipositor and small black wings that look a little narrower and longer than a fruit fly's wings. When they get startled they fly a few circles  around the "nesting" site and then return to it, very few of them seem to ever wander far from what ever soil I find them in.  Oh and they are very annoyingly attracted to peoples eyes and hair >/


----------



## infinitebohr (Mar 4, 2012)

Well honestly I was sure I had Phorid flies as I swore there was a hump in the back. If you look at pictures of Fungus Gnats online, they also have a hump-like shape, so I found that to be misleading. Again, I used a lab microscope to identify my pests as fungus gnats so that may not be a possibility for you, but the key indicator for me were these little secondary wings behind the main wings. That and they looked more "waspish"...so you probably have fungus gnats that you thought were Phorids...like me!! 

If you go to Google images and search "phorides2.jpg" the first image will be a comparison chart. The one on the left is the fungus gnat, the middle is the Phorid fly, and the one on the right is a fruit fly. Hope this helps!


----------



## BenjaminBoa (Mar 5, 2012)

Definitely fungus gnats! The Sciarid fly had the same pointed ovipositor I saw, and I definitely would remember those bizarr muscular back legs the phorids have... almost looks like cricket legs.


----------



## infinitebohr (Mar 10, 2012)

I figured I'd go ahead up and upload for people's future reference incase the link goes bad.
Left: Fungus Gnat  / Middle: Phorid Fly  / Right: Fruit Fly

Reactions: Like 1


----------

