Trachelyopterus insignis

[Kostas]

Hello,

I just got 2 of these I think, bought as Colombian woodcat but IDed them as this species. How can I sex them at about 12cm size? The store was selling them as Fisher's woodcat, which they seem not to be, so I tried seeing them by the dorsal hump and wasn't very able to of course. I now saw the males have a modified anal fin. But how do I really spot this? What's the easiest and sure way to sex them at this size? I could get two more if I have to, to increase the odds, but wouldn't like multiple males fighting for example.
They are in a 200g tank

Thank you very much in advance

[Kostas]

Is this is a male? What do you think?












What do the different sexes look like in this species?

I don't have a photo of the second one, only saw it at dusk and need to check them when both are out with better light

[Kostas]

I got another two today as they are supposedly a social species and wanted to help them feel secure and at ease to cruise throughout the day. I took some photos of the new ones

Specimen (No. 2). Female?

[Kostas]

Another(No. 3)(the one in the front). Can't really decide. Male/female? The one in the back is the No. 2 specimen

[Kostas]

I think I have one sure male, no1, and the rest are debatable. What do you think?
How to I tell apart T. insignis from T. fisheri?

Thank you very much in advance

[bekateen]

How to I tell apart T. insignis from T. fisheri?

Are these our only two options? (I'm not familiar with this group, so I don't know if it's something other than one of these two). But if it is for sure one of these, I'm inclined towards fisheri. Although yours don't appear to have the crazy big dorsal spine present in fisheri, there is this little detail from the CLOG pages:

Another feature that gives its identity away is the terminal mouth, whereas other Trachelyopterus species have a slightly superior mouth (see also General notes).

I've taken two of your photos, cropped them and rotated them to make the fish approximately horizontal. In both photos, the mouth appears to be more terminal in position than superior in my opinion (although to be transparent, the photos are not taken from a perfect side aspect, so I could be wrong on this). Anyway, if I'm guessing, I'm guessing and choosing only between these two species, I'd go with fisheri.

Cheers, Eric

[Kostas]

Thank you very much for your reply Eric!

The mouth does is terminal on my fish. But so it is in the T. insignis photos I can find, so it's not very clear to me. None of the specimen has a dorsal fin shape like in the fisheri photos, including my 15cm long male(no1).
The common name they are sold under is Colombian Woodcat, so I *assume* they at least are a Colombian species, otherwise, yeah, they can be any species. They were imported as T. fisheri buy from what I find on the net from the European importer, they must be insignis(smaller final size listed and no strange dorsal is shown or described for differentiating the sexes). But I find my specimen agree more with the insignis photos than any other. As you can see, the head "shield" is not very visible on my fish like its on other species. Maybe they are small? Or maybe that's the typical

Cheers,
-Konstantinos

[smitty]

I can answer whether it is male or female. But that is one nice cat.

[Martin S]

From the general body shape and the images, maybe two different species? To me, the fish in the first 6 pics isn't the same as the other images, but I could be wrong? I'm not sure if the 'twisted' dorsal of

Trachelyopterus fisheri

is a feature that develops as the fish matures? @Marc Van Arc is the man, maybe he will be able to chip in with a reply? And regarding the sex of the fish, it may be easier to wait for them to mature a little and try again. Sexual dimorphism can be hard to spot in juvenile fish, but can also get easier as they mature.
HTH
Martin

[Kostas]

Thank you very much for your replies!

Thanks smitty, I thought the same too! I quickly checked final sizes and sexing, and got them. Its very rare to see these here and i had space in my 2m tank!

The body shape and everything seems the same from up close. The first 6 photos where taken from a strange angle and the image may be somewhat distorted. The only thing i wanted to show as much in detail as i could, was the anal fin shape/texture. The first specimen is the biggest of all, at 15cm size and has a developed gonopodium. The rest are from 10cm to 13cm and i need to check them again in detail. I really need to sex them as i probably won't have another chance of getting any more if i don't have both sexes and i would like to breed this species if possible.

I am not sure when the strange dorsal fin develops. but since that is a big and bony extension, i think it should at least start developing in half grown specimen like these. I am sure the sex characteristics will be more subtle than in mature, adult fish, but we more or less always have to sex them the earliest possible when getting fish small and need particular sexes. In my group of 4, i really need to be sure 1 is male(which i think i am sure no1 is) and at least 1 female(now thats the difficult part...female or undeveloped male? And how do the anal fins of females of this species look like?)

I really could use any thoughts and opinions on this subject from anyone knowledgable on this group of catfish. Its the first time i keep Auchenipterids and everything about them has been totally new to me, including their sexing and behaviour. I really did not know what to expect but the more they settle in, the more i like and enjoy their behaviour. I find it very interesting that they hide in the most exposed of places while there are plenty of dark hiding holes in the tank. But no, these prefer to just set next to a Cryptocoryne clump or on Microsorium leafs. Or just find a dimly lit, secluded area and just lay down. And they love current. They go swimming against the spraybar flow and play with it sometimes. One i got with rot on its dorsal fin puts the damaged area in the full flow from the spraybar to clean the tissues(they are all slowly healing nicely from their wounds and rot on fins and barbels). Interesting fish. One has already come to eat from my hand!

[Martin S]

Am going to stick my neck out and say these could be

Trachelyopterus insignis

, though the CLOG images for this fish aren't the best reference. From the lack of twisted dorsal, none of the other

Trachelyopterus

appear to match, so very difficult to be 100% sure for me.
The head markings do have some resemblance to something I've seen but I' just can't place it!
Martin

[Kostas]

I feel the same way about them. Even the head and dorsal fin markings match with the CLOG photos, though indeed the photos were not good enough to judge adequately the characters to be 100% sure

Any ideas on sexing at their current size?

[Martin S]

Any ideas on sexing at their current size?

I have to admit I struggle with sexing these fish, the smaller

Centromochlus

are generally much easier, but the larger species such as these I find difficult. You may be right with fish 1 being male, and 2 female, but I can't be sure of the sex of the fish in the other photos, I was hoping Marc or Steve (@The.Dark.One) might chip in, but ultimately, the photos aren't the best for sexing and think, considering your situation of being unlikely to see any more of them being available anytime soon, enjoy them, feed with a good mix of frozen/live and prepared foods and as they mature, any sexual dimorphism should become more apparent.
HTH
Martin

[Kostas]

I also can't be sure when trying to sex them as i don't know how a female is supposed to look and how a developing male. I am finding it quite hard to know. Even for the no1, i don't know if it truly is a male or if the first ray of the anal fin is supposed to look like that in any sex(a bit thickened). If you noticed, the no1 has an anal fin with the leading edge being longer, then the fin reducing and then the fin beginning its typical curved shape. Other specimen have the leading edge barely longer and others only have the anal fin curved with no longer leading edge. These are all younger though than the big one, so i am not sure if this develops with age or if its a sex characteristic. Any experience or photos of the different sexes in this species or related ones, would be most appreciated to get a better idea what i am looking for

I can provide better photos for sexing if i know what i need to show in detail. They are pretty outgoing and i think i do can photograph them better

The reason i need to know if i have both sexes is that i do have the chance to buy more of them NOW but i will probably not get a second chance in the near future. I do feed them with bloodworms and a mix of quality prepared catfish foods + shrimp pellets and they gorge themselves like there is no tomorrow. They were quite skinny when they got here and seem to be gaining some mass

Warm regards,
-Konstantinos

[Martin S]

If you can get better photos, side-on with a clear view of the anal fin area, that would definitely help.
Glad to hear they are doing well.
Regards
Martin

[Kostas]

Thank you Martin

I am trying for better pictures.

What do you think of this one?




And this one? Might be the same fish, not sure


One of them has lost the markings of its lower body and its lower half is mostly white with the exception of the fins which have retained the markings. Is this indicative of a certain sex or maturity? The rest are fully marked, top to bottom, others very intricately, others less so.

Thank you very much in advance

[Kostas]

I see they change color at will... They can become plainer or intricately patterned at will. 1 is always darker but don't know if it means anything. There are squabbles among them and split fins happen

Any general help sexing them even with other species in the family as examples or even confirming their ID would be great