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[Kerry]

Hoping someone might know what these are. found them in large numbers in the sump of my tank. Stuck to the glass and anything else they can. Don't move much but can feel them moving on my fingers. Any help would be much appreciated.

thanks

[Tired]

Look like pineapple sponges, but hard to tell with them smushed. Do they look like tiny white pineapples stuck to things? 

Pineapple sponges are completely harmless, and tend to grow only in dark areas anyway. Very common in reef aquaria.

[Kerry]

Hi thanks for the reply, They look a little like pupae of some sort of insect. Hard to get them off the glass but they are fat and I guess resemble pineapples.

cheers

Kerry

[Tired]

You can see a picture of pineapple sponges in the first post on this thread, or you can look 'em up online for pictures. A scraper will probably take them off the glass better, if you want them out, but they're completely harmless and will likely pop back up again anyway. 

[aSaltyKlown]

Saw this guy for the first time today.  Not sure if it's a Chiton, Sphaeromatidae or something else?  If it wasn't in my tank, I'd just call it a roly-poly! 

TIA

[Tired]

That looks exactly like a roly-poly. I'm pretty sure it IS. There's one striped just like that, and saltwater isopods usually have tails. I think a roly-poly fell in your tank. They can last decently long underwater, though it's probably drowned by now.

 

That said, you should catch anything that looks like that. That's definitely an isopod. Roly-polies are terrestrial isopods (which makes them crustaceans, like crabs! They need to live in damp places because they breathe with gills), and many saltwater isopods are harmful. There are a couple of harmless kinds, but you should catch isopods as a general rule, to verify that they are in fact a harmless type. Munnids are the most common harmless ones- anyone reading this can look up pictures. Lots of legs. 

[mcarroll]

11 hours ago, afrostyreefer said:

A google image search for "marine isopod" reveals a ton of lookalikes for this.

 

Doubful this guy is actually a terrestrial species unless there's a plant nearby that was recently brought indoors or some other vector.

 

For the record, your specimen looks nothing like the typical isopod you'll see in a forum post or google search for "parasitic isopod".

 

Parasitic isopod identification is very sketchy, but internet lore says the parasitic ones have large, dark eyes (for night-hunting sleeping fish....their m.o.).  But your isopod has typical "bug eyes" that are more or less small and camouflaged.

 

I'd guess yours is a detritivore or scavenger just like his terrestrial lookalike cousins.

 

See Wikipedia's entry for Woodlouse under the section on their Ecology which mentions the amphibious (ancient) and aquatic (modern) branches of the family – including marine species.

 

Interestingly, they (not sure which species) are apparently kept as pets on their own merit.

 

[Tired]

It's specifically the stripes that are throwing me. I know I've seen a terrestrial isopod that looks exactly like that. It would be weird for one to be in the tank, but not impossible. 

 

The best thing to do with an isopod in the tank is take it out and find out what it is. If it's harmless (and mcarroll is right that the small eyes are a good sign), it can just be put right back into the tank. I should rephrase: there are a great many species of isopod, most of which aren't predatory. But in reef aquaria, there are generally only a few species encountered, and some of them are definitely predators and a very big concern with fish. This doesn't appear to be one. 

 

I've kept roly-polies/woodlice as pets. Pretty much any terrestrial species can be kept as a pet, usually with ease, though some of the big, fancy-looking Spanish species are harder to keep happy. They're popular as pets among people who like bugs as pets, because they're very easy to maintain and don't tend to escape. Just keep them on some moist dirt, give them some leaf litter, and occasionally sprinkle in some fish food or other protein source. There are pretty kinds, too- zebra isopods and dairy cow isopods are popular. It also helps that they don't bite, sting, fly, or do anything else that people tend to find objectionable. 

[mcarroll]

These (or ones like them) are apparently (from Googling) really common on some Atlantic beaches....plague-level, scare-the-beachgoers common sometimes.  I don't know why they're so rare in aquariums/why one has shown up in this aquarium though.  Pretty odd no matter what type it is.  I wouldn't expect much different behavior from one of these when compared to an amphipod of similar size.  Would be interesting to have!

[aSaltyKlown]

I normally think of myself as a pretty good Google sleuth and found all types of info as well as here and other forums.  But did not see anything that would nail this one down. 

 

Thanks for the replies and the recommendation to search "marine isopod" - this seemed to have nailed it.  

 

I haven't seen it again, hopefully I can get a top down picture once I see it.  I'm still curious as to where it came from.

[Tired]

Unless it's a terrestrial one that came in from who knows where, it was likely on your rock or a coral frag. Maybe hidden on a big snail shell. 

[Jerad81]

After looking at this post I think this might be a stromatella? I just found it in my tank today and thought it was a snail at first but it doesn't appear to have a shell. Plus, looking at it closely, it appears to have some tiny spikes sticking out of it's back. Sorry my pics aren't the greatest, the camera on my phone can be a little frustrating, but I hope they are good enough for someone to officially id it. Thanks for the help!

[Tired]

Looks like a nudibranch. A stomatella has a small shell, like a tiny shield, on its back. Nudibranchs are generally the color and texture of their food, so I'd take a wild guess at this one eating some sort of black sponge. 

 

That being said, I suppose it might be a baby elephant slug. Get a pipette and gently blow on its back, to try and annoy it. Elephant slugs have a small white shell hidden under their mantle, and will show it if they try to retract away from a threat. 

[Jerad81]

1 hour ago, Tired said:

Looks like a nudibranch. A stomatella has a small shell, like a tiny shield, on its back. Nudibranchs are generally the color and texture of their food, so I'd take a wild guess at this one eating some sort of black sponge. 

 

That being said, I suppose it might be a baby elephant slug. Get a pipette and gently blow on its back, to try and annoy it. Elephant slugs have a small white shell hidden under their mantle, and will show it if they try to retract away from a threat. 

Ok, that's good to know, thank you! I will definitely keep a pipette handy. It pulled a disapearing act on me after I took the pics but next time I see it I will give that a try.

[Tired]

Nudibranchs in aquariums (assuming that's what this is) generally don't live very long, because they tend to have extremely specialized diets. You may never see it again. As a general rule, unless a nudibranch is the color and texture of a coral you want to keep, you don't have to worry about it. Extremely flamboyant ones that are flashy as a "poison!" warning are an exception, they don't usually resemble their food, but they're also quite rare as hitchhikers. 

[Minireeftank]

Anyone know what this is? 😕

[mcarroll]

Tunicate?  Lucky!

[Tired]

If it sort of closes those two siphons down when approached/touched, it's a tunicate. Tunicates, also called sea squirts, are harmless filter-feeders. They frequently don't live long in aquaria because they need a lot of filtered food, but the worst it'll do is die. The best it'll do is grow and be neat. Interestingly enough, that little guy is one of our closest non-vertebrate relatives. Tunicates start out life as a sort of boneless tadpole, which has a notochord. The notochord is the foundation of the spinal cord, like vertebrates have. They just opt not to use it for much, once they find a good spot to settle down, glue their heads to the substrate, and grow into a bag of nothing. Our other closest non-vertebrate relative is the lancelet, which is something like a simplified, boneless fish, and is a sensible animal that starts mobile and stays mobile instead of starting mobile and turning into a coral impersonator. 

[mcarroll]

Good descriptions!  

[Sealybomb]

Seen this worm for the first time this evening. It’s below the sand so probably not the easiest thing to ID. Looks about an inch long but could be longer. Has black markings and a black looking head (top right of pics) will keep an eye out to see if I can get better pic but not likely.  Any ideas?

[WV Reefer]

1 hour ago, Sealybomb said:

Seen this worm for the first time this evening. It’s below the sand so probably not the easiest thing to ID. Looks about an inch long but could be longer. Has black markings and a black looking head (top right of pics) will keep an eye out to see if I can get better pic but not likely.  Any ideas?

Looks like a peanut worm. 

[Sealybomb]

15 minutes ago, WV Reefer said:

Looks like a peanut worm. 

That was my guess too (had a look through some other ID thread). 
question is..... when you see something like this for the first time should you dig it out to get a better look at it? Maybe can get a better pic then to ID it....

[WV Reefer]

3 hours ago, Sealybomb said:

That was my guess too (had a look through some other ID thread). 
question is..... when you see something like this for the first time should you dig it out to get a better look at it? Maybe can get a better pic then to ID it....

If you are worried you can but more often than not most hitchhikers are no big deal. 

[Sealybomb]

32 minutes ago, WV Reefer said:

If you are worried you can but more often than not most hitchhikers are no big deal. 

Decided to leave it be .... the wife was disgusted by it though 🤣

[Tired]

Digging it out might help ID it in future, but wouldn't likely work. Burrowing worms are tricky to get ahold of. Observation without disturbing it and making it hide is probably more useful than digging about to catch something that's nearly guaranteed to escape.