2mm long brown critter, what am I?

[Hufsa]

As if I didnt have a bad enough day yesterday, I also discovered a new species in my tank, one that I have not seen before. It doesnt seem to be planaria and it doesnt look like the rhabdocoela I have seen. Does anyone recognize this? It is 2mm long, I tried taking pictures with my handheld microscope but unfortunately it was hard to get clear pictures on this scale and its quite speedy. It appears to have two dark "eyes" deep inside the head, and has no other visible organs that I can discern.

 

[MichaelJ]

As if I didnt have a bad enough day yesterday, I also discovered a new species in my tank, one that I have not seen before. It doesnt seem to be planaria and it doesnt look like the rhabdocoela I have seen. Does anyone recognize this? It is 2mm long, I tried taking pictures with my handheld microscope but unfortunately it was hard to get clear pictures on this scale and its quite speedy. It appears to have two dark "eyes" deep inside the head, and has no other visible organs that I can discern.

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Hi @Hufsa Not 100% , but it looks like planaria to me - they can be brown... it could also be an entirely new species - in which case you get to name it! Hufsaria perhaps?

What happened yesterday btw?

Cheers,
Michael

 

[Hufsa]

looks like planaria to me

Nooooooooooooooooooooooooooooooooooooooooooo
..please be wrong Michael

I thought the triangle head / little ear flaps was required for planaria?
Its head is very pointy, no sign of flaps. Its also fairly "fat", not very flat

Hopefully not a new species, but if so I will name it timetonukethetankaria. No way this nasty little thing gets named after me!
Right now I mostly want to get a flamethrower and burn my entire tank, so I am hoping this thing will rather turn out to be harmless rather than predatory

 

[X3NiTH]

It’s a Nematode and it’s a fat one!

Tough call as to what type though, could be either B or D.

 

[jaypeecee]

Hi @Hufsa

Please take a look at this, third photo on the page:

Planarian flatworms - | Aquasabi

Detection and treatment of harmful flatworms

www.aquasabi.com

JPC

 

[MichaelJ]

I thought the triangle head / little ear flaps was required for planaria?

Yes, well, I am not sure... it looks like a sort of flatworm to me. But anyway, @X3NiTH is probably right on this one.

Cheers,
Michael

 

[X3NiTH]

This is the candidate offered up by @jaypeecee, it’s actually a very good fit, never seen a brown one like that before.

The mouthparts on @Hufsa picture look like a nematodes though and what looks like eyes may be deeper internal structure, hmm dunno now I’m not sure, @Hufsa needs a better microscope! Leaning more towards it being Planaria now though.

Put some bait in see if you can tease more out,

 

[Mr.Shenanagins]

I’m not convinced this picture didn’t come from your toilet, what are you trying to pull here?

 

[MichaelJ]

I’m not convinced this picture didn’t come from your toilet, what are you trying to pull here?

LOL... That thought did strike me as well when I saw @Hufsa's pictures.

Ok, Planaria takes the lead! (Sorry about that @Hufsa)

 

[Jaseon]

I’m not convinced this picture didn’t come from your toilet, what are you trying to pull here?

And its a big fat one by all accounts.

 

[sparkyweasel]

I’m not convinced this picture didn’t come from your toilet, what are you trying to pull here?

If it did, I would be worried about those eyes.

 

[arcturus]

LOL... That thought did strike me as well when I saw @Hufsa's pictures.

Ok, Planaria takes the lead! (Sorry about that @Hufsa)

Trying to give some hope to @Hufsa: isn't the "tail" of that thing too pointy for a planaria? @Hufsa: we need more photo evidence! But I am not sure if Nematode D above would be a better critter to have in the tank... that one looks dangerous...

vs

 

[Wookii]

I’m not convinced this picture didn’t come from your toilet, what are you trying to pull here?

That post brightened up my morning - almost spat my coffee all over my desk! 😂🤣

To @Hufsa - can you put the offending worm in small glass and shine a torch behind it while taking another photo - it might make it easier to ID (e.g. if you can see the 'eyes' planaria have), also a video of its movement might help, including if you can get it to free swim.

 

[Tyko_N]

I'm no expert in freshwater flatworms, and judging by the lack of information out on the web I would say that few people are, but I would guess that is a Rhabdocoela (similar to this one). I would expect more distinct eyes, head and intestine on a planarian, but more photos (preferably from below as well) would help if you can manage to get some @Hufsa. Overall, I think it's probably a harmless detritus/algae feeder, and I wouldn't be overly worried, although keep your eyes open for more.

 

[Hufsa]

I have the two discovered specimens in a cup in my windowsill, will try to take better pictures later today

Stay tuned for more "turd VS planaria"

 

[Hufsa]

I took more photos today, the improvement in quality is unfortunately not massive, but unless you all are interested in crowdfunding a microscope then there is not much to do 😅
I tried to include small photoseries that show its movement. When it encounters a wall it will retract its front end into its body, I dont know if youve ever seen a manatee or a seal crash into a glass pane but it looks exactly like that.
The dark patches that looked like eyes in one picture, I think are not eyes, just some other anatomy. It always carries its tail in a point, and the nose is also quite pointed but looks to have a slight indentation (opening?) ala @X3NiTH 's nematode pictures. Its very fat as some of you have pointed out, and is the same thickness all the way around, it does not appear to have a typical underside and will roll around indiscriminately. Sorry to disappoint but it is not a turd.
The tank is being treated for Scutariella so has been dosed repeatedly with Praziquantel and Levamisole.
Critter is obviously not fussed about these medications.
Based on this my ID so far is: Not planaria
Treatment plan: kuhlii loaches

 

[pat1cp]

Someone with more knowledge than I will be along soon.......but the debate will continue.

Is the partner happy about this ?

 

[Hufsa]

Planarian flatworms - | Aquasabi

Detection and treatment of harmful flatworms

www.aquasabi.com

Thanks for this link JPC I have now learned that they do not need to have ear flaps to be planaria

movement might help, including if you can get it to free swim.

It doesnt seem to free swim, will crawl along surfaces but detaches and falls if disturbed, it curls itself into a small ball also.

 

[dw1305]

Hi all,

It doesnt seem to free swim, will crawl along surfaces but detaches and falls if disturbed,

Does it move by looping? or does it glide?

cheers Darrel

 

[Hufsa]

Hi all,

Does it move by looping? or does it glide?

cheers Darrel

It glides, doesnt loop. Ive seen small leeches before and it does not move like a leech, fortunately for me