Ropefish? Nopefish - Maybe A Loach? - FW Fish ID - 10/04/12
Hi there all at WWM, love your informative site and snappy responses!
<Love your kind words! Sabrina here, who adores all things odd and creepy!>
I've been running a well-planted 20ga for the last year or so, with a dozen zebra/Longfin Danios in there. All is pretty okay in terms of water parameters (ammonia, nitrate, nitrite 0, ph 7.5).
<So far, very good.>
Now a friend is moving out of province and wants to give me some fish - I said no to his convicts
<Good move - these would quickly outgrow (and overpopulate!) your 20g tank.>
but there's a crazy looking fish in there I want. It didn't grow much since he's had it in the last year and is quite small (good intentions, poor husbandry skills) - is it possible he's stunted the fish?
<Mm, well, possible, but.... let's keep going....>
Fortunately it's mouth is too small (currently) to eat his or my Danios
<A Ropefish of almost any size would be "iffy" at VERY best with zebra Danios.>
and I know that if it is indeed a Ropefish, I'll be able to upgrade to a larger tank shortly.
<If it IS a Ropefish, Erpetoichthys calabaricus, and you DO take it, you'd want to upgrade, well, urgently. They're rarely offered for sale less than 8 or so inches in length, and at that size, and considering their active, boisterous personalities, would need more than a 20g tank.>
So: it's dark brown-black,
<Strike one.... A Ropefish would be "muddy" dorsally, paler ventrally; not blackish.>
3-4 inches long,
<Strike two.... E. calabaricus is ALMOST never offered for sale at this size. It does happen, but very seldom.>
and about half the diameter of a ballpoint pen. What differentiates it from all the Ropefish I've seen is, rather than no dorsal fin, it has a short, rectangular dorsal fin, about a half inch long by a quarter inch high, 2/3 down its length.
<Strike three.... This isn't a Ropefish.>
The caudal fin flares outward with stiff spines supporting a similarly squared edge, like a shovel, instead of the diamond-shaped caudal fins I see on other Ropefish and bichir. It does however have four small mouth appendages and I have seen it burrowing in the substrate between making occasional darts to the surface of the water. It definitely doesn't resemble a caecilian, dragon goby, fire eel, or a bichir.
<Sounds identical, however, to a "black Kuhli loach", which could be one of a couple species, probably of genus Pangio.... links:
http://www.loaches.com/species-index/pangio-oblonga
http://www.loaches.com/species-index/pangio-pangia >
Forgive me if I'm mistaken, but I was under the impression that Erpetoichthys was the only species in its genus?
<Well, E. calabaricus is the only species of the genus Erpetoichthys. I think that's what you meant.>
Is there anything else that this wiggly, mellow little worm could be that I missed?
<As above.... I think it's a loach. Especially now that you use the terms "wiggly", "mellow", and "little worm".... very apt descriptors for a black Kuhli.>
And if I'm lucky and it actually is an Erpetoichthys,
<Aren't you lucky even if it's not?>
what will happen to the dorsal fin as it matures?
<If it is a Pangio, it's probably already mature.>
Should I expect this if/when I acquire more Ropefish?
<If you add an actual Ropefish, it will probably eat the loach first, and snack on the Danios later. But fortunately, if it IS a loach, it is pretty much compatible with the Danios - but would really appreciate soft water with a pH 6.5-7.0 if possible.... Check out your friend's tank's pH and see how far off it is from yours. Stability is most important, so if your friend has had the little guy in a pH similar to yours for an extended period of time, it may do quite well in your tank's pH of 7.5. That is, however, higher than I'd like to keep this sometimes delicate fish. Also, Pangio are gregarious. He wants conspecific friends. If you can't find conspecifics, other Kuhlis will do. In the US, it is easier to find some of the banded Pangio. Look here:
http://www.loaches.com/species-index/pictorial-species-search-index/serpentine-striped-brown-to-black-bands-over-yellowish-ground-color I'd recommend a minimum of five (though preferably more!) for most Pangio.... The more the merrier. Plus, they are TONS of fun to watch. You'll love this
fish.>
Sorry that I was unable to add a photo, thought I'd ask an expert anyway!
<A photo would make for a more sure ID, but your description is very good.
I hope I've landed this one, but if it does not resemble Pangio, do please consider snapping a pic.>
Thanks again, Hilary
<Best wishes to you and your new Pangio pal, -Sabrina>
Re: Positive ID on a Ropefish?     10/5/12
Ah! A Kuhli? Thanks so much!
<Glad to help.  -Sabrina>