Blood sucking/flesh eating isopod

[Tavero]

Hah, the joys of owning a reef tank.
I've restarted my tank with fresh live rock 3 months ago because of several issues. It was running fine since then but it seems l have introduced some kind of isopod pest into my tank. One of the flesh eating kind. How do I know that? Well I was bitten while feeding my corals right now. I was able to remove that bugger out of my tank because it was stuck to my finger, but I'm worried this isn't the only one because pests never come alone. One also seem to have bitten my Molly. There is a bump on the tail.
I don't know much about the ecology of flesh eating isopods so I need to ask the obvious question: do I have to worry to experiencing a scene from the Alien movies? Do these things burry into living fish or even lay eggs into them?
I am still surprised how these things were able to reach adulthood between my rockpool shrimps. Usually they devour any crustation smaller than a few millimeters. The had to hide really well.

 

[ISpeakForTheSeas]

Do these things burry into living fish or even lay eggs into them?

My understanding is that the kinds of isopods (and potentially amphipods) that might bite people like this (i.e. carnivorous/parasitic ones) brood their eggs in a pouch on the female's underside, so they wouldn't likely lay eggs inside the fish (or your hand).

I can't say for sure exactly what kind of pod you have without pics, but Cirolanids are known to do this sort of thing on occasion (I've heard of this happening with both Cirolana and Excirolana species), so I'd guess you have a Cirolanid of some kind. I can't totally rule out other kinds (such as Corallanids) that are known to feed off of people on occasion too, but they seem to do so more rarely. Either way, if it's an isopod that's biting people, it's almost certainly from the Cymothooidea superfamily.

 

[Kzang]

Not sure what you got, but when I first started, I got live rock from my LFS and I got a cirolanid isopod. It would attach during the night, feed, then drop off during the day. The only way I caught it was I looked at the tank in the morning and it was still attached.

 

[Tavero]

My understanding is that the kinds of isopods (and potentially amphipods) that might bite people like this (i.e. carnivorous/parasitic ones) brood their eggs in a pouch on the female's underside, so they wouldn't likely lay eggs inside the fish (or your hand).

I can't say for sure exactly what kind of pod you have without pics, but Cirolanids are known to do this sort of thing on occasion (I've heard of this happening with both Cirolana and Excirolana species), so I'd guess you have a Cirolanid of some kind. I can't totally rule out other kinds (such as Corallanids) that are known to feed off of people on occasion too, but they seem to do so more rarely. Either way, if it's an isopod that's biting people, it's almost certainly from the Cymothooidea superfamily.

No pic for now because I flicked the isopod on the carpet after pulling my hand out. At least it's out.

Funnily enough when I first felt the sting I thought it's one of my greedy rockpool shrimp again trying to rip off dead skin. They do that sometimes and it hurts but never draws blood.

The isopod was able to pierce skin in a matter of seconds.

 

[KrisReef]

No pic for now because I flicked the isopod on the carpet after pulling my hand out. At least it's out.

Funnily enough when I first felt the sting I thought it's one of my greedy rockpool shrimp again trying to rip off dead skin. They do that sometimes and it hurts but never draws blood.

The isopod was able to pierce skin in a matter of seconds.

Man up and quit messing around with these tiny predators. Stick your bare hands in the tank and when you get a bite remove your hand and dip it in fresh water, maybe with a little Iodine and Potassium Chloride to keep the operation clean and efficient. Keep at it until the biting stops.

Don't you watch super hero movies?

That's the way to roll!

Also, if you do find another one, snap and post a pic so @ISpeakForTheSeas can give us a proper ID. Won't be long until another live rock reefer encounters what you have, imo.

Out here in CA we have cirolinids that used to get in our sampling buckets and bite my coworkers. I never got bit presumably because the bugs were afraid of catching a bad blood born pathogen from me?

 

[Tavero]

Not sure what you got, but when I first started, I got live rock from my LFS and I got a cirolanid isopod. It would attach during the night, feed, then drop off during the day. The only way I caught it was I looked at the tank in the morning and it was still attached.

So they just feed of the blood and then hide again? Similar to moskitos or bed bugs? But can they actually reproduce in tanks? Thats the important question.
I will probably have to get a red light to check the tank at night because I have never seen one by using a normal flashlight.

 

[KrisReef]

So they just feed of the blood and then hide again? Similar to moskitos or bed bugs? But can they actually reproduce in tanks? Thats the important question.
I will probably have to get a red light to check the tank at night because I have never seen one by using a normal flashlight.

Interesting idea, a lot of reef bugs and planktonic life will swarm when you hang a Point light source over the side of a boat. You may be able to exploit this fact to collect them if you have more than one? I would also suppose they are not asexual self replicators so with luck you got the first and last one? Waiting for results in future posts. Hope this isn't a huge problem to fix for you, either.

 

[ISpeakForTheSeas]

So they just feed of the blood and then hide again? Similar to moskitos or bed bugs?

It depends on the kind/species and life stage of the pod, but some parasitic/carnivorous pods do basically exactly that; others will latch on and stay on for days; some will literally latch on and only let go if you peel them off or if their host dies; some only do these things while young; others transition from one style of feeding to another; etc.

But can they actually reproduce in tanks? Thats the important question.

If you have a male and a female of the species and they have enough, proper food for them, yes; they could reproduce in the tank.

As mentioned above, these pods literally brood the eggs (and in at least some species, the larvae through their first molt or two) in a pouch inside the female's body. After the eggs hatch, the females release their young as basically miniature adults, so the young should be able to swim and hide like the adults can.

Interesting idea, a lot of reef bugs and planktonic life will swarm when you hang a Point light source over the side of a boat. You may be able to exploit this fact to collect them if you have more than one? I would also suppose they are not asexual self replicators so with luck you got the first and last one?

This is an interesting idea - I have no idea if they'd exhibit positive phototaxi (i.e. if they'd swim toward the light), but it'd be cool to find out, and it could potentially be useful for removing them. I know some species from the same superfamily do swim toward light, and they're known (at least as larvae) to swim to the surface during the day and to dive sown to find fish to feed on at night, so it's definitely worth a shot.

To my knowledge, they shouldn't be able to reproduce asexually (though in some species, the males may be able to turn female, so having more than one in a tank regardless of the sexes may enable reproduction).

 

[Tavero]

Man up and quit messing around with these tiny predators. Stick your bare hands in the tank and when you get a bite remove your hand and dip it in fresh water, maybe with a little Iodine and Potassium Chloride to keep the operation clean and efficient. Keep at it until the biting stops.

Don't you watch super hero movies?

That's the way to roll!

Also, if you do find another one, snap and post a pic so @ISpeakForTheSeas can give us a proper ID. Won't be long until another live rock reefer encounters what you have, imo.

Out here in CA we have cirolinids that used to get in our sampling buckets and bite my coworkers. I never got bit presumably because the bugs were afraid of catching a bad blood born pathogen from me?

Well look at that. After sucking blood another one seemed to appreciate a more balanced diet and was craving for some frozen artemia.

Flicking it on the carpet also seems to be a bad idea because it was able to crawl around outside of water fairly fast and far. It also survived pure ethanol for almost 15 minutes. Talk about sturdy.
Edit: size is 6.5mm. larger than I thought. The one that bit me was definitely smaller.

Are these eggs? Please don't tell me they are eggs. They are eggs right?

 

[EeyoreIsMySpiritAnimal]

This article has some possible ideas for catching/ trapping them...

https://reefkeeping.com/issues/2006-02/bp/index.php

 

[Tavero]

First time I stained a sample. I think I overdid it and now my fingernails are blue... A sacrifice I did for science.

 

[EeyoreIsMySpiritAnimal]

He looks so cute and harmless... Lol

 

[KrisReef]

First time I stained a sample. I think I overdid it and now my fingernails are blue... A sacrifice I did for science.

Ultra Blue Fire & Lightening Bugs- Rare! $79.99 each + Shipping.

 

[ISpeakForTheSeas]

Sorry, haven't had time to find a key and figure out isopod morphology until today - I didn't realize that I would need super clear pics of the various mouthparts to key out the family and super clear pics of the various tail-parts (top and bottom) to key out the genus, but it is for sure in one of the following families: Aegidae, Cirolanidae, Tridentellidae, and Corallanidae.

As mentioned above, based on known people-biting species, it's probably either a Cirolanid or Corallanid species, but if you can get some super clear close-ups of the mouthparts and tail-parts (pretty much everything from the last pair of legs back), I can narrow it down more from there.

For anyone curious, here's the family key:

American Isopod and Myriapod Group - Cymothooidea

Main Page | Isopoda > Cymothoida > Cymothooidea Suggested Common Name: FisheatersNumber of subordinate taxa: 1405 species in 9 families worldwide, 246 species in 7 families in our areaEtymology: after Cymothoa Fabricius, 1787, see that account for more information. Common name refers to this

www.americanisopodsmyriapods.com

And here are some pages with diagrams to figure out the morphology (I like the first and second ones for figuring out the general pieces/makeup of the bodies, but the third is very technically detailed):

Crustacea Glossary

Isopod Anatomy and Biology - Isopod Site

Isopod Anatomy Mature isopods have 7 pairs of walking legs that are pretty much the same. In Latin, "iso" means "same" or "equal" while pod means "foot". However, isopod mancae (babies) have only 6 pairs of legs in their initial instars. Isopods also have 2 pairs of antennae — one large pair and...

isopod.site

Untitled 1

 

[ISpeakForTheSeas]

Are these eggs? Please don't tell me they are eggs. They are eggs right?

Forgot to answer this, but yeah, there's a good chance those are eggs.

 

[Tavero]

Sorry, haven't had time to find a key and figure out isopod morphology until today - I didn't realize that I would need super clear pics of the various mouthparts to key out the family and super clear pics of the various tail-parts (top and bottom) to key out the genus, but it is for sure in one of the following families: Aegidae, Cirolanidae, Tridentellidae, and Corallanidae.

As mentioned above, based on known people-biting species, it's probably either a Cirolanid or Corallanid species, but if you can get some super clear close-ups of the mouthparts and tail-parts (pretty much everything from the last pair of legs back), I can narrow it down more from there.

For anyone curious, here's the family key:

American Isopod and Myriapod Group - Cymothooidea

Main Page | Isopoda > Cymothoida > Cymothooidea Suggested Common Name: FisheatersNumber of subordinate taxa: 1405 species in 9 families worldwide, 246 species in 7 families in our areaEtymology: after Cymothoa Fabricius, 1787, see that account for more information. Common name refers to this

www.americanisopodsmyriapods.com

And here are some pages with diagrams to figure out the morphology (I like the first and second ones for figuring out the general pieces/makeup of the bodies, but the third is very technically detailed):

Crustacea Glossary

Isopod Anatomy and Biology - Isopod Site

Isopod Anatomy Mature isopods have 7 pairs of walking legs that are pretty much the same. In Latin, "iso" means "same" or "equal" while pod means "foot". However, isopod mancae (babies) have only 6 pairs of legs in their initial instars. Isopods also have 2 pairs of antennae — one large pair and...

isopod.site

Untitled 1

Easier said than done. Getting a clear image is one thing, making a photo of that is another. Meanwhile that guy is totally dried up. Looking through the microscope is a lot clearer but my camera is crap.
That's the best I can do.

 

[NanoJHB]

Can't help with the question, but wow that photography is nextt level good ! You've really got some skills

 

[ISpeakForTheSeas]

Easier said than done. Getting a clear image is one thing, making a photo of that is another. Meanwhile that guy is totally dried up. Looking through the microscope is a lot clearer but my camera is crap.
That's the best I can do.

Yeah, it is definitely easier said than done (and the photos you've gotten have seriously been really good).

Unfortunately, I can't make out enough detail on the mouthparts (which isn't terribly surprising since they're layered and the specimen is kind of translucent), but if you can see them clearly, you may be able to key it out yourself; you basically need to look at the shapes of four of the stacked layers of the mouth parts (the mandibles, maxillipeds, and maxillae - the "Crustacea Glossary" link above shows where and what these are) and the key linked above can tell you specifically what to look for.

 

[Tavero]

Yeah, it is definitely easier said than done (and the photos you've gotten have seriously been really good).

Unfortunately, I can't make out enough detail on the mouthparts (which isn't terribly surprising since they're layered and the specimen is kind of translucent), but if you can see them clearly, you may be able to key it out yourself; you basically need to look at the shapes of four of the stacked layers of the mouth parts (the mandibles, maxillipeds, and maxillae - the "Crustacea Glossary" link above shows where and what these are) and the key linked above can tell you specifically what to look for.

Are you a biolgist? I looked at your links but to be frank, that stuff went straight over my head.
While that topic is interesting, if I'm able to get rid of them and never see or hear from them again I am happy.

I will try to use traps with fish innards and report back how it goes. Hopefully that mix of blood and bile is a more appealing meal for this annoyance.

 

[ISpeakForTheSeas]

Are you a biolgist? I looked at your links but to be frank, that stuff went straight over my head.

No, I'm just an author with an undergrad psychology degree who likes learning new things.