Mystery hitchhiker fry ID. Surprise puffer?

[MrGibson]

Hey y’all. 
 

Tonight while sitting in front of my medaka grow out tank I noticed a little fish along the bottom that I didn’t put in there. I was only able to get some pretty terrible pictures of it. The current theory is it’s maybe a puffer if some sort based on its movement. It stayed near the bottom and slowly moved from spot to spot while moving its eyes in the orbits and picking food off the bottom. It’s hard to tell because it’s so small but it appeared to not be using its tail to swim and was moving very slowly and smoothly. 
 

I’m assuming this fish had to have come in as an egg on a plant or something and hatched out in my tank. I’ll attach the pictures I was able to get even though they suck in hopes it can inform some guesses. I’m thinking I may camp out in front of the tank with my dslr and a macro lens for a few hours this weekend to get a better look. If I’m able to I’ll update this thread. 
 

 @mountaintoppufferkeeper I know you keep and breed some puffers. Any ideas?

 

thanks y’all!

 

 

[mountaintoppufferkeeper]

Cool. Congrats. Its tough to see in stills. I  do a video on the phone and make it a gif for the short videos here. Spotted congo for comparison

 

And pao palustris

basically tiny foodbellys with eyes from very early on

I had a mystery flag fish fry before that made it through a sump overflow rack and multiple predators until discovered around that size. It probably went through the pump at least once as egg and new fry. Tracking that down now will update with that gif once found

 

[MrGibson]

On 3/1/2024 at 9:58 PM, mountaintoppufferkeeper said:

Cool. Congrats. Its tough to see in stills. I  do a video on the phone and make it a gif for the short videos here. Spotted congo for comparison

 

And pao palustris

basically tiny foodbellys with eyes from very early on

I had a mystery flag fish fry before that made it through a sump overflow rack and multiple predators until discovered around that size. It probably went through the pump at least once as egg and new fry. Tracking that down now will update with that gif once found

 

Appreciate the comparisons. I’m definitely going to try for some video this weekend. Im not certain it’s a puffer but I’m having trouble thinking of anything else that moves like that. I’ve got a new light coming Monday as well so that may help brighten things up for better visibility. I’d say it’s probably around a half inch or so right now but that’s really a guess based on the few glimpse I got of it. I’ll be sure to update if I get any video

 

thanks 🙂

[mountaintoppufferkeeper]

Found it ...eventually :). Pretty cool whatever it becomes.

 

[Odd Duck]

Here’s some pea puffer fry for comparison starting younger.

 

[MrGibson]

Update! It reappeared!

I’ll work on getting a gif posted

[MrGibson]

I gave up on a gif. Here’s a link to a video.

 

any ideas? The movement of the mouth has me thinking it’s not a puffer. 
 

side note, does anyone know the term for fish mouths that extend forward like that? Just curious

[MrGibson]

@Fish Folki know you’ve worked with a good number of species. You ever seen a fry like this?

[Fish Folk]

I’m not sure. I thought Jordanella floridae at first glance… maybe a little male… but that doesn’t seem right. To my eye, the Dorsal + Caudal fin pronouncement seems to preclude Puffer… but I’ve never raised juvenile Puffers. 

[Colu]

I was going to say Florida flag fish @Fish Folk

[MrGibson]

On 3/3/2024 at 9:22 PM, Fish Folk said:

I’m not sure. I thought Jordanella floridae at first glance… maybe a little male… but that doesn’t seem right. To my eye, the Dorsal + Caudal fin pronouncement seems to preclude Puffer… but I’ve never raised juvenile Puffers. 

Flag fish crossed my mind as well, largely from @mountaintoppufferkeeper’s post, but I’m not really sure. I may try to figure out who I’ve bought plants from and see what they think. I’d agree on it not being a puffer at this point. 

On 3/3/2024 at 9:32 PM, Colu said:

I was going to say Florida flag fish @Fish Folk

Seems like this is the leading theory at the moment. 

[MrGibson]

Looking further into this tonight I’m thinking I can maybe say it’s some kind of pupfish, similar to flag fish. The only issue I’m seeing is that most pupfish have truncated caudal fins whereas this appears to have a rounded caudal fin. I guess it’s possible that shape changes with age maybe?

 

so far I think the closest match I’ve gotten is desert pupfish but I don’t believe those are commonly kept, and again the caudal fin is off. 
 

And thus the rabbit hole goes deeper. 

[Odd Duck]

Definitely doesn’t move like a puffer although I can certainly see why you thought it might have been initially.  Every puffer species I’ve ever seen closes the tail a lot and uses it to turn in place vs mostly using their pectoral fins to turn (although they will do that, too).  But they usually have some color in their tails and flick them the tiniest bit to rotate on the spot.  They will curl their bodies right up when they spin in place.  Plus the mouth isn’t right.  No guesses from me although I think you’re on the right track with pupfish / flag fish body type. 

[MrGibson]

On 3/7/2024 at 3:52 PM, Odd Duck said:

Definitely doesn’t move like a puffer although I can certainly see why you thought it might have been initially.  Every puffer species I’ve ever seen closes the tail a lot and uses it to turn in place vs mostly using their pectoral fins to turn (although they will do that, too).  But they usually have some color in their tails and flick them the tiniest bit to rotate on the spot.  They will curl their bodies right up when they spin in place.  Plus the mouth isn’t right.  No guesses from me although I think you’re on the right track with pupfish / flag fish body type. 

Yeah puffer is for sure thoroughly ruled out. I think at this point the best way to narrow down the ID is to grow it out lol