Bug Identification - "White tick" and "Single tentacle worm"

[Lavyathan]

Hello!

I run a 5 gallon PICO tank that until yesterday had no fish. I also feed phyto daily, so there has always been an abundance of wee beasties that have fascinated me. Most I've been able to identify (copepods, amphipods, munnid isopods, spinoid worms, spirorbid worms). However, there have been some worms with a single tentacle that I've been unable to identify, and today I noticed a new 'bug' that looks like a solid white copepod to the naked eye, but very different under a microscope. I've named the below pictures "worm" and "tick" until I can identify. Any help that people can provide, or a link to resources to help identify?

 

[StatelineReefer]

First is a ciliate of some sort.

Is the second motile or sessile?

 

[Lavyathan]

First is a ciliate of some sort.

Is the second motile or sessile?

Thanks, I'll look into the first!

The second is pretty well stuck in place from what I can tell, but the tentacles extend/contract to a crazy degree where I can't see their base when fully retracted.

 

[taricha]

First is ostracod, second is a micro giant squid. (Jk, no idea on the second)

 

[StatelineReefer]

Thanks, I'll look into the first!

The second is pretty well stuck in place from what I can tell, but the tentacles extend/contract to a crazy degree where I can't see their base when fully retracted.

I'd love to say what it is, but I can't because as with many small sessile invertebrates, theres no distinguishing features on it.

It does incorporate nematocysts into it's appendages, so I would say it's probably a very tiny anemone... ball or aiptasia.

 

[KrisReef]

"Sea fleas are tiny carnivorous crustaceans. There are hundreds of recognised species, and they feed mostly on dead marine life such as fish, crabs, sea birds and even whales, but will nibble live human flesh if it's convenient. Many are so small a microscope is required to recognise them.Aug 7, 2017"copied from the source of all life and information, the web.

 

[Lavyathan]

First is ostracod, second is a micro giant squid. (Jk, no idea on the second)

Interesting, I should have guessed that there would be saltwater ostracods, I have a ton in my freshwater tanks.

 

[Lavyathan]

I'd love to say what it is, but I can't because as with many small sessile invertebrates, theres no distinguishing features on it.

It does incorporate nematocysts into it's appendages, so I would say it's probably a very tiny anemone... ball or aiptasia.

I have observed plenty of larger specimens in my tank, and they don't seem to turn into either ball nems or aipasia, and I don't have any that I've found in my tank besides a couple mojanos I've been meaning to get rid of. Instead they stay as one long, reaching tentacle that almost has the shape of a peacock feather to my eyes. With the microscope I can now tell that those little polyps are what make up the feather shape.

 

[StatelineReefer]

I'd love to see the larger form, if you have a picture of one, could you also take another slide image of the 'worm' focusing on those little tentacles?

I see a little more definition in picture 3, and now I see why you call it a worm, originally I thought that was a ridge of an oral disc. I'm curious now...

 

[Lavyathan]

I'd love to see the larger form, if you have a picture of one, could you also take another slide image of the 'worm' focusing on those little tentacles?

I see a little more definition in picture 3, and now I see why you call it a worm, originally I thought that was a ridge of an oral disc. I'm curious now...

I definitely plan to! I'll see what pictures I can get in the next week and update here. The microscope pics are a little hard to get, as they are usually attached to sand or rock, so it makes it hard to get a slide cover on to get the entire worm in focus.