Tatia nigra?

[paul dixon]

That would be Tatia nigra, I suppose. We need a couple of photos of these, as there are none in the Cat-eLog

That's good enough for me as well

Wrt your last posting: the revision only shows dead specimens; I prefer live ones. But thanks anyway for the offer/attempt to make some pictures. Curious about what these look like.

These are two pairs of F1 adults that I dropped off to Steve's last Friday. Here's a couple of not great 2007 pics of the juveniles as they started to sex out.

Tatia sp. violet 024.jpg (19 KiB) Viewed 3468 times

[paul dixon]

Tatia nigra - and another

[paul dixon]

and another Tatia.

[Marc van Arc]

Thanks Paul.
Normally I'd say these are most likely T. aulopygia (changed the lenght of this species in the Clog), but after having a closer look at the "Revision of Tatia"-paper I have to admit things have become rather confusing.
Steve had already "warned" me in another post that the Clog information on some Tatia spp may no longer be accurate.
A paper that showed live specimens as well would be nice for us amateurs, wouldn't it?
I wonder if there's a reason for showing only dead specimens - I take it these newly described fishes are relatively fresh caught?


To all CSG and LFS visitors: have a great weekend!

[paul dixon]

Hi Marc
these were identified by Ingo Seidel when he saw them 2 years as nigra. They were originally imported as sp. purple by Pier Aquatics but Ingo brought us up to speed on the new, then, scientific description as nigra. Stunning fish with a velvety purple/black pallor and brilliant white underbelly.
We've had these for about 5 years. Spawned them in October 2007 and they've not gone since.

[The.Dark.One]

Apparently the best way to tell nigra from all other described Tatia (as well as colour/pattern) is that in nigra the post-cleithral process (sometimes called the humeral process) is very short (60% of HL, compared to 80% plus in all other sp). It doesn't reach the vertical line from the insertion of the dorsal fin spine, whereas most almost reach, or go past.

I got some from Paul (at an auction) as Tatia sp. Violet, and one had some small spots on the ventral half of the body when small, but if you check the post cleithral process it is too long for nigra.

See Tatia sp. A on http://www.scotcat.com/thedarkone/auche ... eridae.htm

So if these are the same as the ones in Aqualife, I'm not yet convinced they are nigra.

Just my two penneth.

[paul dixon]

Steve
your hypothesis takes us right back to sp. violet I'm afraid, as there don't appear to be any pictures of live nigra about.
Paul

[The.Dark.One]

Steve
your hypothesis takes us right back to sp. violet I'm afraid, as there don't appear to be any pictures of live nigra about.
Paul

Hi Paul

I'm not saying they are not nigra, just that it's not definite in my eyes. Perhaps sp. Violet's adults' post cleithral process is short? In some catfish I think the length of the pcp in proportion to the head etc differs in different stages of growth. My image is of a semi-adult.

Looking at the images in the clog of 'Tatia aulopygia' the second image looks like T. nigra as it appears to have a very short post cleithral process.

[paul dixon]

Hi Steve
agree entirely with you. I'll have to get some better pics. done and post them up for further discussion.
Ingo and Johny Jensen are on their way here now so I'll try and coerce them into shooting some for us.

[Marc van Arc]

Another way to distinguish T. nigra according to the paper is the fact that both adult males and females have an elongated upper caudal lobe. A female genital papilla is mentioned as well (page 534).

The colour is described as dark brown with light brown fins (caudal is dark brown). That doesn't seem to match velvety purple/black or could this be caused by the alcohol (page 533)?

[paul dixon]

The colour is described as dark brown with light brown fins (caudal is dark brown). That doesn't seem to match velvety purple/black or could this be caused by the alcohol (page 533)?

Alcohol, alcohol, are you suggesting that I had been drinking when I looked at these fish Marc

[Marc van Arc]

The colour is described as dark brown with light brown fins (caudal is dark brown). That doesn't seem to match velvety purple/black or could this be caused by the alcohol (page 533)?

Alcohol, alcohol, are you suggesting that I had been drinking when I looked at these fish Marc

Not really, unless you were drinking while reading that page
Seriously, I was refering to the Soares-Porto paper on the Revision of Tatia. On page 533 there's a description of the colour in alcohol.
I take it you have that paper; if not, let me know and I can send you a PDF.

[paul dixon]

Not really, unless you were drinking while reading that page
Seriously, I was refering to the Soares-Porto paper on the Revision of Tatia. On page 533 there's a description of the colour in alcohol.
I take it you have that paper; if not, let me know and I can send you a PDF.

Hi Marc
would be very happy to receive the paper as I don't have it. Please send to me at the museum.

aquarium@bolton.gov.uk

Thanks Paul

[MatsP]

I have some pictures of the fish from Aqualife (thanks to Jools helping out getting the fish between the glass and a bit of driftwood). I haven't had time to process the pictures yet, but hopefully tonight.

--
Mats

[The.Dark.One]

I have some pictures of the fish from Aqualife (thanks to Jools helping out getting the fish between the glass and a bit of driftwood). I haven't had time to process the pictures yet, but hopefully tonight.

--
Mats

Did the pics come out MatsP?

[MatsP]

Here we go:

Thanks for reminding me.

--
Mats

[The.Dark.One]

Thanks MatsP

As you can see in these images, the post cleithral process is still 'long' in the adults. Based on this IMO these are not nigra though I cannot be sure.

[MatsP]

I said the same thing to Jools when I'd just peeked on the screen of the camera [much easier than trying to spot it on the fish iself, as the flash shows those things much better than the lights on the tank].

Which of course leaves the question of "then what are they?", which I'm afraid I can't help to answer. Nor did I bring them home with me for further study - may have been interesting, but I'd already decided on several other fish, and there are only so many fish that woodcats get along OK with, and I didn't really want to just force them into an unsuitable tank...

--
Mats

[paul dixon]

Well chaps it seems we're no nearer to an answer!!

[Marc van Arc]

and there are only so many fish that woodcats get along OK with, and I didn't really want to just force them into an unsuitable tank...

Not sure what you are trying to say here; could you explain please?

[MatsP]

and there are only so many fish that woodcats get along OK with, and I didn't really want to just force them into an unsuitable tank...

Not sure what you are trying to say here; could you explain please?

Well, I'd have to remove some fish that would like to hide in the same space, and/or would compete for food, or would end up "food". I know I have a fair number of tanks, but it's still a limited number of spaces. One of the unfortunate sides of having most tanks fairly heavily stocked is that it's hard to fit new fish in.

They are also not small, so I expect they would prefer a tank bigger than 60 x 45 cm surface. This limits the number of possible tanks to 5 out of 12. One is a rift lake cichlid tank - not a good plan. I don't want them in with my breeding group of L128 - in case they do breed, the last thing I need is to have a predator that may choose L128 fry as a midnight snack. The next tank I (at the time) had 20+ Ancistrus in it, but I have got rid of the Ancistrus - but it's got my Centromochlus romani already, and my Dekeyseria is now in there, and I will move either the Hypancistrus L066 or the Peckoltia L147 - haven't decided which yet. And I really don't think they would go well in my 1.2m x 60cm tank where I have Leporacanthicus triactis and Orinocodoras. And the RIO400 in the house would definitely not work, with 4 large Synodontis decora, Megalechis thoracata and Geophagus surinamensis (along with a few others...).

So many catfish, not enough tanks...

--
Mats

[The.Dark.One]

Well chaps it seems we're no nearer to an answer!!

I'll try and get the leading centromochline ichthyologist's opinion.

[The.Dark.One]

I've had word back from Luisa Sarmento-Soares (who jointly authored the Tatia revision) and she has confirmed that it is not T. nigra. It is Tatia intermedia as it is currently understood. As you will see from the paper there is a wide variation of intermedia. It may well be that some are described as different taxa in the future but at the moment this fish is Tatia intermedia sensu lato.

In terms of the cat e log, IMO the fish shown under Tatia aulopygia pictured by NTUGuppy is nigra as it has the short post cleithral process. The other two fish show the fish discussed here IMO. If you look at the description of T. aulopygia in the revision the fish in the cat e log don't match. I also think what we have under T. neivai is wrong also. Neither am I convinced about what we have as galaxias.

[MatsP]

Revision is here:
http://www.scielo.br/scielo.php?script= ... 8000300022

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Mats