Hello, I have recently discovered within my axolotl tank that there is a strange aquatic isopod....

[IdentifyThisPod1556]

To give some context, the tank has plants and shrimp. So it is indeed bioactive. I recently fell upon a strange isopod living within the confines of the tank, and although it behaves like a terrestrial species (porcelial), it chooses to live underwater, and posseses functional gills. Please give some info as to what this might be. Thank you.

 

[Scorpiobsession]

About how large is this isopod? Terrestrial isopods evolved from aquatic ones so it was likely a stowaway from one of your elements.

 

[Scp682]

Probably a stowaway or a parasite but that's unlikely since axolotls are all captive bred.

 

[Arthroverts]

That appears to be quite a large specimen!

@Ponerinecat, @schmiggle, thoughts?

Thanks,

Arthroverts

 

[Polenth]

Other than it most likely being some sort of waterlouse (freshwater isopod), I don't know... but knowing that people call them waterlice might help you find out which ones are local to you.

 

[Salmonsaladsandwich]

I suspect it might be Trachelipus, which is a widespread terrestrial isopod that resembles Porcellio but prefers to live in very moist conditions and can survive underwater for long periods.

 

[Poonjab]

Asellus aquaticus. The jerk of the water world.

 

[IdentifyThisPod1556]

I suspect it might be Trachelipus, which is a widespread terrestrial isopod that resembles Porcellio but prefers to live in very moist conditions and can survive underwater for long periods.

Oh, really? Do you have any other info on this species? or is this info from experience? Do tell!

 

[spiderlover123]

About how large is this isopod? Terrestrial isopods evolved from aquatic ones so it was likely a stowaway from one of your elements.

This isopod seems to be around 1 inch. It doesn't seem to have any ability to swim.

 

[IdentifyThisPod1556]

This isopod seems to be around 1 inch. It doesn't seem to have any ability to swim.

To be clear this is my friend. He's the one who discovered the isopod.

 

[Scorpiobsession]

I agree with the Asellus aquaticus guess.

 

[Salmonsaladsandwich]

Oh, really? Do you have any other info on this species? or is this info from experience? Do tell!

They're a rather common species in moist areas in north america and europe, I've personally seen them crawling around and acting normally after falling in water and here's a paper that mentions their ability to survive underwater:

Terrestrial isopod community as indicator of succession in a peat bog - PMC

Terrestrial isopods were studied in the Dubravica peat bog and surrounding forest in the northwestern Croatia. Sampling was conducted using pitfall traps over a two year period. Studied peat bog has a history of drastically decrease in area during ...

www.ncbi.nlm.nih.gov

Regardless of whether my guess is correct though it's definitely not Asellus aquaticus.

 

[Arthroverts]

Trachelipus don't get up to an inch in length however if I'm not mistaken.

Perhaps @Xeroporcellio could shed some light on the subject?

Thanks,

Arthroverts

 

[Salmonsaladsandwich]

Well the size given is an estimate, not exact. If it's not Trachelipus my guess would be some other terrestrial isopod that can survive underwater since it really doesn't resemble any freshwater isopod i'm aware of.

 

[spiderlover123]

Well the size given is an estimate, not exact. If it's not Trachelipus my guess would be some other terrestrial isopod that can survive underwater since it really doesn't resemble any freshwater isopod i'm aware of.

Well to be fair I did measure it exactly to be around 1.20 inches. I am the man who owns the tank with the isopod in it. Sadly while I was transporting it to a cup it it seems i damaged the gill structure which caused it die. Do not lose hope though! I saw some mancae in my sponge waddling around so it seems to have gotten the change to reproduce before its untimely passing.

 

[jay444]

I do not keep isopods or aquatic pets. Yet, I find this post very intriguing and I'm curious

 

[Xeroporcellio]

The habitus is definitely different from Asellota and Cymothoidea (the typical freshwater isopods) and, in fact, is consistent with that of Porcellio scaber and Trachelipus rathkii (the photo doesn't help me to separate between those two options)! Its seemingly longer and more slender body, which could favor the Asellota option, is just an artifact of the photo (taken from the outside of the cup/bottle). The ''gills'' are in fact the pleopods, which have retained the gill-like structure of their ancestors, but now contain a system of ''false lungs'' for breathing on land.

Although a small number of terrestrial isopods have returned to a semi-aquatic lifestyle (check here), no species has become fully aquatic again and will usually drown after some time underwater. Concerning the latter two candidates (P. scaber and T. rathkii), they aren't even considered amphibious (although, as mentioned before, because of T. rathkii's wet habitat, it is more tolerant of freshwater), so it is remarkable that this specimen remained underwater and even successfully gave birth! By the way, when did you first notice its presence in the tank and are there any climbable surfaces-rocks, semi-aquatic plants, filtration gear etc, that stand above water? Also, did you @spiderlover123 keep the female after death? A good photo of the body out of the water could help put a proper name on it.

Some other interesting things that I noticed: a) She was ''HUGE'' (and maybe this character helped her survive a bit more underwater?)! I have seen and collected female Porcellio obsoletus that easily reach 3 cm (ca. 1.20 inches), but I have never found literature records of this magnitude for P. scaber and T. rathkii! b) In the photo, the posterior half of the body (5th tergite and downwards) is paler. This usually corresponds with freshly molted specimens. So, if it isn't another artifact of the photo, it means that she had molted very recently, perhaps less than an hour before the photo was taken!

 

[spiderlover123]

I do not keep isopods or aquatic pets. Yet, I find this post very intriguing and I'm curious

I wouldn't blame you. This is quite the weird case we have on our hands here all things considered. I really don't know how on earth it managed to get inside of the tank considering that my tank has only had exclusively ghost shrimp and amanos for almost 7 months. Another odd thing to be interested in is the fact that we cant seem to identify this species and it seems to have sparked a debate between some people on this thread. Truly this is the most interesting thing to happen to me all year!

 

[IdentifyThisPod1556]

The habitus is definitely different from Asellota and Cymothoidea (the typical freshwater isopods) and, in fact, is consistent with that of Porcellio scaber and Trachelipus rathkii (the photo doesn't help me to separate between those two options)! Its seemingly longer and more slender body, which could favor the Asellota option, is just an artifact of the photo (taken from the outside of the cup/bottle). The ''gills'' are in fact the pleopods, which have retained the gill-like structure of their ancestors, but now contain a system of ''false lungs'' for breathing on land.

Although a small number of terrestrial isopods have returned to a semi-aquatic lifestyle (check here), no species has become fully aquatic again and will usually drown after some time underwater. Concerning the latter two candidates (P. scaber and T. rathkii), they aren't even considered amphibious (although, as mentioned before, because of T. rathkii's wet habitat, he is more tolerant of freshwater), so it is remarkable that this specimen remained underwater and even successfully gave birth! By the way, when did you first notice its presence in the tank and are there any climbable surfaces-rocks, semi-aquatic plants, filtration gear etc, that stand above water? Also, did you @spiderlover123 keep the female after death? A good photo of the body out of the water could help put a proper name on it.

Some other interesting things that I noticed: a) She was ''HUGE'' (and maybe this character helped her survive a bit more underwater?)! I have seen and collected female Porcellio obsoletus that easily reach 3 cm (ca. 1.20 inches), but I have never found literature records of this magnitude for P. scaber and T. rathkii! b) In the photo, the posterior half of the body (5th tergite and downwards) is paler. This usually corresponds with freshly molted specimens. So, if it isn't another artifact of the photo, it means that she had molted very recently, perhaps less than an hour before the photo was taken!

Thank you for the info! As far as I know my friend spiderlover123 claimed there was a small portion of climbable surface to get to higher ground and breathe (IE, a filter and a air pump). It never tried to move to higher ground, nor tried to surface the water. Since the isopod has passed (due to rough handling as he claimed), plans are in order of preserving the dead specimen. It was indeed mid molt, and in my opinion, is some evident proof that this creature was comfortable with living in water!

 

[IdentifyThisPod1556]

Fantastic news! It seems the isopod has colonized the tank! spiderlover123 has claimed there is another specimen with the same appearance and behavior in the tank! So hope is not lost! We are waiting in anticipation to see if this means there are more in the tank, and if so this could be great news!