Corydoras what
6-19/01
Written by Kevin Korotev for the SPLASH, the official publication of the
Milwaukee Aquarium Society, INC.
Corydoras are a favorite. Odd and unusual Corydoras are a passion. Identifying them is a challenge, but spawning them is the ultimate breeder’s adventure. Some Corydoras are rare and unusual BECAUSE they don’t spawn readily. Having said that, I consider this a success story.
For a few weeks in the summer of 2000, there was a new (to me) Corydoras popping up in fish stores all over town. I had no idea what this fish was despite a thorough search of my reference books and the Internet. I narrowed the choices down to 4 possibilities…and stopped. I had to get them first, then grow them to adult size before ANY identification could be attempted. I "collected" 7 of the nicest from 3 different stores and called them the "TinWoodsman" Cory after the character in The Wizard of Oz. Some names just ARE.
You can not force a Corydoras. Maturity takes time, as do experiments with water conditions. This fish seems most active in the classic Cory conditions; neutral pH, soft and cool. They continued to grow for 6 more months and did not appear gravid until a year had passed. By this time my 3 males and 4 females had stopped just short of 3 inches. Having reached this length, 2 of my possible ID choices were eliminated. Frankly though, identification wasn’t on my mind quite as much as it had been. NOW the challenge was to get them spawning.
With the editor’s permission, I will insert a list here of spawning tips, which I’ve included in previous Corydoras articles….
1) Have some tank raised males in the group, as they SEEM more likely than wild males to initiate courtship.
2) Be ready with plenty of good food (live black and frozen bloodworms) when the females FIRST ripen. It seems exponentially harder the longer you/they wait.
3) Keep them cool and change their water (with still cooler water) regularly.
4) Keep a regular, but moderate 'current'. I used a sponge fitted powerhead.
5) Keep the pH under 7.0
Have a big group.
7) Know that there are exceptions to all of these points.
*******
Although I have an opinion, I am still not confident in the true identity of this fish. I will never be. I did not collect it, am not an expert, and can only use pictures of other often mis-identified fish as my reference. I do, however, enlist the help of people I consider very knowledgeable. In the Winter of 2000, after sending some photos to Julian Dignall at PlanetCatfish,
www.planetcatfish.com
) I received an email from Ian Fuller. If you’ve done any Corydoras research you know the name. He was "of the opinion" that the fish was a possible unidentified color form or sub-species of Corydoras Tretlii, but was possibly mis-lead "…by the appearance of red in the finnage". As honored as I was by the response, I admit hesitation in accepting this answer. The PICTURES did show a red tinge, but the actual fish did not appear so. The only other thing to do was get the fish, the actual fish, to another "expert".I have had dealings with J. Eric Bodrock (
www.oddballaquatics.com) of Pittsburgh, Pa almost from my entry into this hobby. I have gained a considerable respect for his knowledge of all things fishy…particularly Corydoras. I wrote him about the fish and piqued his interest. It seemed only natural to then offer him the fish under the condition that he make an identity guess. His enthusiasm was evident in an email sent to me on the night that he received them.Hello Kevin,
The fish arrived this morning, around 10:30, in great shape. They are defiantly different than any that I have. I can also say that I never seen them before. COOL! …
Later:
OK, here we go.
They aren't treitlii, the body markings of these is almost solid & their body shape is narrower.
From all the "variant" photos of amapaensis I could find, they aren't these. They all have a more distinctive body pattern to them & have a longer forehead to the nose.
C. septentrionalis comes in a wide assortment of colors also, but almost always with markings in the tail. Interesting that the Aqualog books say that the septentrionalis are also different ellisae forms?
Not much about stenocephalus out there, but the fish on page 116 of Derek Lambourne's "Corydoras Catfish; An Aquarist Handbook" labeled stenocephalus, sure does look like our guys. But the Aqualog photo on page 90, not even close. Need to find more info on these.
My guess on the fish is probably a color variant of C. ellisae. Photo of ellisae in Seuss's book , page 173, and photo on page 706 of Burgess's 1989 "An Atlas of Freshwater & Marine Catfishes" show the exact fish we have except for just a very, very faint marking in the tail. The body, shape, and color of these photo's match ours pretty darn close. I'd have to say at this point that that's what they are…
Still Later:
Hey Kevin,
I found another photo of C. stenocephalus in The World Of Catfishes, by Midori Kobayagawa (TFH Publishing), page 92. The photo is the fish that we have… Our fish is most likely stenocephalus. (Until more info is found to show they aren't!)
Thanks,
Eric
…And that becomes the final word…"Until more info is found…"