HCA: Hermit Crab Association

Someone at the HCA found a bug on a dead crab and it was identified as Megaselia scalaris, a fly that feeds on almost anything, but will prefer decaying matter - like dead crabs. They lay their eggs into the stuff the feed on, so if you found them on a dead crab, they may already have layed their eggs into the body.They are not really parasitic, since they don't feed on living crabs, but I couldn't think of a better word Here's a picture:http://www.phorid.net/phoridae/mscalaris.htmlThey are similar in size and shape to a fruit fly (actually, I misidentified them as fruit flies at first on the HCA), but fruit flies don't have a hump like those flies.You can find some more info here:http://ohioline.osu.edu/hyg-fact/2000/2144.html

Ah you beat me to it! Here are some pictures and the content of the thread:A member at HCA discovered these in her tank and inside the shells of her dead crabs.This is the info collected at HCA in regards to these bugs:TardigradePost subject: Jinjurale's bug identified! Hi Guys, This is Megaselia scalaris (Loew), a cosmopolitan, often synanthropic, polyphagous, scavenging phorid. They often attack injured or weakened invertebrates, especially in cultures of ****roaches, crickets, tarantulas, etc., but I've never heard of them infesting hermit crabs until now. Henry Disney (who keeps track of such things) will also be interested, so I cc'd him on this too. Brian ___________________________ Brian V. Brown Curator, Entomology Section Natural History Museum of Los Angeles County 900 Exposition Boulevard Los Angeles, CA, 90007, USA Telephone 213 763-3363 FAX 213 746-2999 bbrown@nhm.org www.phorid.net Wow. When he says polyphageous (eats anything), he means it. These flies have been found living in shoe polish, blue paint, human cadavers in formaldehyde and lungs in living people ! It also may be responsible for an outbreak of rashes in US schools. They are a "neo-tropical" species, but also a "tramp" species, meaning they hitch rides all over the world in shipments. It probably was in the crab when purchased, since it was at the store and are rare in cold climes like Minnesota. This is something that could happen again, so we should know it is out there. They appear when organic matter is rotting, exactly what Melin said. I guess that's why she's the teacher. Henry Disney was cc'ed this message. He is THE world expert on phorids, so you guys are famous now and will probably end up in some text book. And let's not talk about folk-cures. _________________ MelinI have these bugs in my classroom right now. They are always a clear sign something is amiss. Yep, they come with the crickets (As do the mites) and they feed on the dead. I am not concerned about them at all. I never see them unless there is decaying matter. Once the body is discovered they take off... presumably for another host. I have them because i was hoping my crab might be molting, but he died. I knew he died by the flies and later the smell. Bugs really are good! The are a strong indication of lots of things. I think. One thing i do recommend is cleaning the tank or area where you might have found the bug. They come to dead creatures fast. And my doors and windows are always open. I think that is part of why they come so fast (not to mention climate) BUT, if they are laying eggs in the substrate then you want to be sure those are gone. I have never seen them on a molter, but i dont want to take the chance. Good show Tardigrade!! Did it say they drown in water? Cuz i am pretty sure they do! Thanks for the props above. Honestly, i am only speaking from experience not scientific knowledge. I observe everthing though. Sometimes a little too much... _________________ Daethian Very valuable information! So will there be a follow up on how to deal with this with the hermit crabs? What happens when you have the bugs in your tank but no decaying matter for them? Will they eat on the crabs?? Are they drowndable???_________________ Melin Daethian, i have been looking stuff up on line, with Tardigrade's help, and it seems to be the same thing i have had. When there is no decaying matter, the flies leave. I would certainly bathe the crabs on a regular basis. And i will do that too. Just in case larva has been deposited. But I haven't seen them in my main tank. Just my ISO where my crab died. Every time i have had a death, they showed up. And left almost as quickly. Honestly and i don't mean to say the person with infestation is wrong, but i don't think the bugs stay unless there is some decay or bacteria festering. In her original post she said she could hardly stand it the stink was so bad and that she might have a dead crab. My guess is that the flies noticed the death early on. As soon as that crab passed... If they are bad enough they could be deposiing eggs. Only my guess on what i have seen with mine and read... Bathing and a complete clean up should take care of the problem. JUST my best guess... Still looking into it and I know others have entomologists or some contacts working on this._________________Jedediah Thank you! That's interesting and I'm glad we found out for sure what it is. I collect bugs that appear in crabitats, so here's another one for my collection I still wonder about the crippled wings - maybe the fly was newly hatched and the wings had not hardened yet? I found an article that states that they are attracted to those yellow sticky traps. I used those in my crabitat a while ago to get rid of gnats and they can be attachted to the lid of the crabitat where the crabs cannot reach it._________________Daethian Thanks Melin. Obviously the drastic measures given before are not necessary then. Clean and sterilize everything to remove any eggs or larvae and it should be fine. Great job guys!!!

Talk about speaking too soon! I got this message tonight:Daethian,Jinjurale just emailed me. She said she followed all the steps given to her but lost another crab today. Again with bugs. She said one of her crabs was behaving suspiciously, moving in and out of its shell. She pulled the crab from its shell and found maggots and a fly. This was a live crab, previously healthy. The crab is now in a new shell. It is pretty clear to me that these phorids can be a big problem. In Melin's case, she was not 100% sure it was the same bug, but even if it were, Melin's bugs may not have yet developed a taste for live crabs. I put the three emails and the two pictures on my web site. The links are as follows:James Whitfield emailBrian Brown emailHenry Disney emailhttp://homepage.mac.com/jimgibbs/.Public/Disney%20email.txthttp://homepage.mac.com/jimgibbs/.Public/Brown%20email.txthttp://homepage.mac.com/jimgibbs/.Public/Whitfield%20email.txtFrom the Disney email, you will see that these flies can subsist within living human flesh (myiasis). If they can do that, there is no reason that they cannot subsist on a living crab. They are facultative parasites and that appears to be what is happening in jinjurale's case.I am thinking that this is a desperate situation and that the usual hygeinic principles will not suffice. The crab she removed from its shell had worms and flies, which she killed.I think taking the crab out of their shell like she did may be extreme and dangerous, but safer and more certain to work than that soap treatment. If I were to do that, I would chill the crab in the fridge for 15-20 minutes to make them slow. It is not likely to die from this, but it may. Then take them out of the shell and boil the shell. Carefully remove any worms on the crab. Kill the worms. Worms on the body are larvae of the flies. Do not flush them or dispose of them live in any way. Look for eggs, maybe with a magnifying glass. Any eggs will be on the crabs arranged in a cluster or in the shells. Kill those too, like the worms. Don't dispose of them live. Make as sure as one can to remove ALL worms and eggs because we don't want to have to do this again. That is what I might consider doing myself if I were as desperate as her. I realize this is dangerous and unconventional, but I am convinced her crabs will die if she does nothing. I would do it if I were in her shoes.And I remind you that doing nothing is also unsafe.**end message**Here is her (jinjurale's) log of what has transpired, this does not include the above information.How do I get rid of bugs and what are they? Go to www.misterboogrey.com/bug.html to see it.My previous posting was removed by the directors, it was what I posted after having a guy tell me how to get rid of the bugs. Because it was removed I thought that he had to be wrong and did not do what he said to do to get rid of the bugs. Below is what has been happening. I am afraid that I will lose all my crabs in my 20 gal tank. Does anyone know anything about these bugs????Below is what has been happening to me or should I say my crabs. Should I try what this guy told me to do? So far I have lost 5 crabs, all had one or more bugs in their shells.-------------------------------------On Tue Mar 08 - One of my crabs, Tango Mango (Indo) started acting weird 4 days ago. At first he kept filling his shell with water so I could see it in there and he was already missing his 2nd left leg when given to me, but he seems to have more trouble moving now.Today when I got home he was sitting in the deep water dish half way out of his shell. I picked him up and he barely moved and his eyes seem to be hanging down. I put him into ISO by himself. I have been having trouble with temp and humidity fluctuations, but now of the other crabs seem to have any trouble.On Fri Mar 11 - When I checked on Tango Mango he looked much better today. He is holding up his eyes and pulled back into his shell.I changed the food and went to eat my dinner. When I looked back in there he was eating. His eyes look like they have white flakes on them. I have had several other crabs molt, but never saw any signs of it so I'm not sure if he is going to molt.On Sat Mar 12 - Tango Mango was at the food dish eating, later he was in the hideout that I made for him.On Tue Mar 15 - Tango Mango just sits in the hideout. When I looked at him, he pulled back into his shell.Wed Mar 16 - Tango Mango and he looks dead, there is no movement or smell. What should I do? Molting? The sand around Tango Mango is getting dry, misted around him.Thu Mar 17 - Tango Mango died, had him for 6 months. I am pretty sure what is wrong - it’s a bug. Found a bug in the shell, the tail part of Tango Mango looked like it was being chewed on. It took 1/2 hr to get bug out of shell. Took pictures of it.Kale (Rug) was sitting in the water dish, when I picked her up she seemed weak. Put her in ISO. Took a look at her before bed and she was in the water dish and barely moved. I took her out and set a coco hut over her.Fri Mar 18 - Asked about bug at pet stores, everyone at 6 different pet stores said that it was nothing that they have seen before and nothing that is fed to pets. Asked about bugs at University and was told that it was a tropical bug and that they would try to find out exactly what kind. Asked a guy (no idea how to spell his name) I knew who is from the Philippians (I think, can't remember for sure) who sells hermit crabs about it. When I showed him the bug (live in a plastic bag) he looked shocked and then upset. He killed it, he wanted to make sure that it did not get to his 100 or so crabs that he had right there to sell.He said that it is a very dangerous bug to hermit crabs. This guy (sorry I don't know his name) explained everything more than once before he wanted to hear why I had the bug and showed it to him, he said he does that because the bug is so bad. The bug is from the tropics so it can't live here outside of the crab tank in Minnesota because its to cool for them. He didn't know the English name for the bug and I didn't understand what he called it.The bug lives in the crabs shell and lays eggs. The larva hatch and eat the crab. When the crab dies the larva leave to become the adult bug and so on. Most people never see the bug because they have a few crabs and never replace them, they are most often only noticed when the bug population is way up when the crab is given a bath. He said that pet stores like Petco make him angry with the way they take care of crabs and that they don't disinfect them before selling them.How to get rid of the bugs:-You will be using warm chlorinated water and turning the crabs to get rid of all air bubbles in the shells.-Indo's and E's are the most sensitive so the only way to get rid of the bugs is to bath them in chlorinated water every day for 5 days. Chlorine kills the bugs but slower than the method for other crabs.-For all other types of crabs you will use Dial unscented antibacterial soap. Don't use any other type of antibacterial soap other than Dial or you will kill your crabs. What you do is put chlorinated water in a bowl, rub the soap in your hands and rinse in the bowl of water, you will have enough soap when the water looks cloudy. Give the crabs (not indo's or E's) a bath in the soapy chlorinated water, they must be in it for 3 minutes. Then rinse the crabs in chlorinated water until all the soap is gone. You will need to bath the crabs in the soapy water 3 times. Sorry I can't remember if he said 3 days in a row or something else. I will go talk to him again to make sure

, but I won't be able tofor a few days.***Important: Even if you crab is molting you must bath it. It is better to take a chance on killing a molting crab than to kill all your crabs and if the crab that is molting is infected it won't survive for long without getting rid of the bugs in its shell.Now the tank:The sand, gravel or what ever you use needs to be sanitized. Also sponges.Wash the inside of the tank with Dial unscented antibacterial soap and rinse well. Do the same for all dishes and decorative items including shells. With the shells be sure to rotate them to get all the air out.Sat Mar 19 – Kale died, had her for 1 year, her body was a mushy, when I cleaned the shell I found a dead bug. Sterilized the ISO tank.I was going to start bathing the crabs the way I was told, but my posting about it in the Hermit Crab Association website was removed.So now I’m not sure if the guy was telling me the truth or what, the HCA WM has not contacted me either about it.Someone on the HCA site thought it was some kind of fruit fly and suggested I use red wine with a drop of dish soap in it to get the bug,so I’ll try that. Also trying a piece of over ripe banana and cantaloupe.Unnamed from Petco (PP) was sitting next to the water and kept moving around in its shell like something was wrong in there. I thoughtmaybe sand so I bathed the crab, no sand or anything came out. Later when I looked in the crab was sitting in the water dish, took it outand set at other side of tank. Later it was back in the water and looked week. Put in ISO.Sun Mar 20 – Last night off and on I kept checking the tank to see if I could see any bugs around the wine and fruit – no signs of any.Unnamed from Petco about 3 weeks ago (PP) died. It had 3 bugs in its shell.Tue Mar 22 – During the night it started smelling bad in the room again, this morning 2 more crabs were dead.Unnamed from Petco, got about 3 weeks ago (Cav) died. It had 4 bugs in its shell all were dead.Moonflower (not sure type, white crab) died. Had her for 3 years. She was under the sand, had to dig for her, was so bad I didn’t search for any bugs.The University has not gotten back to me about the bugs yet.

Hm - we might end up in phorid literature after all.But this is really alarming. I think I will check my roach and cricket colony for those flies, just to be sure - I don't want to end up with them in my crabitat or other terrariums.I agree that bathing probably won't get rid of those flies and that bathing with soap, as this guy suggested, is very likely to kill the crabs. Taking the crabs out of their shell is a desperate measure, but I can think of nothing better to get rid of those flies when they have infested the crabs. If you notice any flies in your crabitat, make very sure that they are Megaselia scalaris before trying the freezer method!

I copied my post from the HCA:I have read on this website:http://ohioline.osu.edu/hyg-fact/2000/2144.htmlthat those flies are attracted to yellow sticky traps. It's worth a try.If you can, put all the crabs that are in the infested tank in ISO alone. The flies have a life cycle of about three weeks so if the crabs were in ISO for your weeks without anything happening, you can assume that there are no more flies on them. Maybe the crabs should be kept on damp paper towels that are changed every evening.I know it's a lot of work and it will be hard to keep up the right temperature in the mini-ISOs, but you can at least make sure that any crabs that are not yet infested with those flies stay healthy.Unfortunately, I have no idea how to get rid of the flies and especially any larvae and eggs that are already on the crabs short of pulling the crabs out of their shell after cooling them down. Bathing doesn't seem to help and I'm really not sure that bathing with soap will kill the flies, but I'm rather sure it will kill the crabs. On the whole I think that cooling the crabs down in the fridge is the better method. I know it's dangerous and I hope we can come up with something better. If anyone else reads this: please don't try this if you have any other bugs in your crabitat - you can get rid of those with bathing and cleaning the crabitat!Another idea: how about offering the flies some decaying crickets or something similar? They will be attracted to those, lay their eggs there and if you change the bait every day, you might get rid of the flies. But I'm not sure this will work.