PlanetCatfish.com

Apologies first but I shall just cut & paste from another elsewhere so I reserve the right to revisit and clarify if required (if it can't be done later). So here goes...

Here's a spanner in the works...

Virtually every reference says P.brevis = L205 = LDA078 as clearly stated on:
Planetcatfish, Scotcat, Wikipedia, fnzas, planetacuario etc etc etc....
http://www.planetcatfish.com/common/spe ... es_id=1339

And then I found this...http://www.loricariidae.no/loricariidae ... _L205.html
L205 is often confused with Peckoltia brevis
And...http://www.plecoplanet.com/forum/showthread.php?t=10815
If you follows...(Armbruster, 2008), then Peckolita brevis (LDA 78) and Peckoltia sp. "L 205" identical... (although I cannot see either LDA or L number mentioned in the reference)
However it then goes on to say:
...Peckolita brevis (LDA 78) and Peckoltia sp. "L 205" but can be clearly distinguished. The most easily recognizable difference is the fine dots on the head:
Peckoltia sp. "L205"- the fine points goes to the dorsal fin.
Peckoltia brevis - the fine points, stops well before the dorsal fin.

P. brevis has aged an orange color. The body shape is different.
(Look Seidel/Evers "Wels Atlas 2" or Seidel "Back to nature" )
(And another ref that I failed to bookmark!)

So despite the vast majority of sites, profiles and care sheets(including here!) having P.brevis, L205 and LDA078 being synonymous (PC included so I may look in to referring that to the mod gods) apparently they are not as they are different beasts both physically and in markings (subtle maybe but deifinately there).
(Edit: Not found much on LDA078, it just send to be stated its P.brevis and I haven't got a ref for comparison, scientific or otherwise)

There is also one important detail I should note: Origin!
L205 is stated as coming from the Rio Ucalayi, the very same locale that has been repeatedly stated as not having any such fish (re P.brevis)

Same fish as described on a German website:
(edit: will try to get the ref if required...sadly I forgot to bookmark it!)

Ucayali Dwarf Pleco, L 205, Peckoltia sp.
This fish is about 10-12 cm, as the name suggests, is home to the Peruvian Rio Ucayali...It is the L 205 NOT to Peckoltia brevis, these two species are often confused or incorrectly declared...

And so my m+f pairing of these fish...

I bought these from as L205s (the only label on display) from a shop who I know orders not just from wholesalers but also direct from importers. Discussions confirmed these were from the latter.
I have not done a Pb vs L comparison on them since finding the new refs but would not be surprised if I did discover they were true L205. Pre-purchase, and working on the info assumption that Pb=L (because that's what all the site I looked at said at the time), I simply checked their id vs other small Peckoltias and visually similar related types and did not do a forensic analysis (pointless with them being juveniles and much smaller 2 years ago).
I would put pix but Iike so many plecs it would involve having to lift them out and that would likely mean a chase which would disturb the whole tank, something I am not going to do just for curiosities sake. I would rather wait to here about the species divide before I get my hands wet (I do have older pix but not much recently that shows the markings clearly enough)
...
Conclusion based on references:

The PC profile in detail is correct, however it has a gross error is that it refers to 2 different species and so needs splitting - the current one is fine for L205 but the true Peckoltia brevis/LDA078 needs a new one from scratch (which may upset some folks 'my fish' listings but it can't be helped - unless the current data is cut and paste to a L205 profile, and the P.brevis is kept but with the date tails amended - 6 of one, half dozen of the other...)

...unless someone can explain how the two distinct species can for on one page, or rubbish the references using science as opposed to assumptions.
....
Enough said, about time I hit submit!...D.

Yeah, I've got both fishes and I'm pretty sure they're not the same thing. It's just a matter of updating the site etc.

I would be careful using internet references, it is very hard, often impossible to figure out how reliable they are basically because being right or wrong about such things is actually more relative and not absolute as one might think. You also need a deep history / knowledge of the sites to understand the source of the data. As you say "virtually every site" refers to L205 = P. brevis but that's because when I put the original l-number pages online in 1997, they were copied as even back then there was at least a small understanding that a lot of the info in the only other source of l-number info in the English language (Aqualog) was a bit inaccurate. As a related aside, during that time, I made up a few common names for common l-numbers and, hey presto, ten years later I walk into an LFS on the other side of the world and see that fish being sold with that name. It's all to do with an understanding of the background/history as I say.

As an example of the right Vs wrong thing, using the same logic as we see here, we would find that everything we are quite happy calling is not but it is hard to find a website that would take that view. So much of what we might want to say is right or wrong boils down to how hard it is to redefine it and the impact of doing so.

Another reason for data being like this is that many real experts eventually slide away from arguing the toss and thus cleansing the data. This is because the number of folks who can write 1500 word responses to whatever the issue is, is always greater than the number of experts and so, eventually, experts stop contributing or become very selective. Or spend more time on lowest common denominator social media sites as it's human nature to be happy as opposed to grumpy and many of those sites it's easier to be recognized as an expert before interaction begins. Then end point however is the general improvement of sites like PlanetCatfish through expert dialogue diminishes. This is unfortunate (in my view tragic) but, I think, temporary, in the future it will improve I think.

So, in matters like this, experience has shown me at least that it's about pulling together all the data and making your own mind up rather than hiding behind references - something I've learned over what is now nearly two decades of running this site. The only reason I know about the whole L205/P. brevis thing is because I got the described species from Yann and I have enough trust in what he tells me about their origin. I also understand the history of the L-number publication and collection patterns to know that it is unlikely they are the same species and that L205 is probably a species awaiting research - maybe one that one of the several resident pleco ichthyologists on the site like Milton or Rupert might want to have a go at. I can, by the way, provide fin clippings of both the Rio Purus and Rio Ucayali fishes. (Hint Hint).

Anyway, I will split the two up at some point and I think a CotM would be a good idea to explain the background. Hope that explains the position and that I didn't rabbit on too much.

Cheers,

Jools

Thanks for the reply Jools.

Hopefully you can see I haven't just based my conclusions on a 'Wikipedia says...' type set of references but scoured long and hard for multiple unrelated documents to back up my case hopefully covering both local, importer, respected and scientific based evidence (there was one with actually body measurements comparisons well beyond the basic longer/taller. Sadly I believe this is one of those I didn't bookmark, although I haven't cleared browser history so it's lurking somewhere in there). I even finally tracked down a PDF of Armbruster, 2008 that had been quoted so often but never with a url attached...

What I'd like to find now is the point that LDA078 was absorbed in to P.brevis as this has eluded me thus far.

Referring to Armbruster I also noted there is that even a notion that the 'true' Peckoltia brevis may not be so clearly homogeneous as he didn't include some example due to 'irregularities'. (My words not his which were likely much more scientific but which are burried deep in the PDF).

Another odd thing was Armbrusters distribution map of P.brevis where the specimens studied were from a widely separated locales across the main Amazon basis, which in itself is not an issue as it just implies a widespread fish species. What piqued my interest was they were all from distant tributaries with none in the central region - perhaps a further clue when it comes to there being not only populations but maybe subspecies and even new species...

...which fits in nicely with the mention of C.aeneues (such a common species yet oddly I've never kept even a single specimen!). This appears an equally well spread species, if not more so. The major differences, however, being that the populations of these fish, in general, are much more clearly connected and not reliant on long swims across flooded forests in order to set up viable new populations. Did I stumble across an article around here somewhere...? (I'll put it on the 'to do' list...)
.....
So with the L205 moved on the the Ichy gods...let's get busy with my Entomocorus gameroi which may take even more digging as early searches came back as 1 population in a lake and everything repeated from there...more late nights...this is assuming the discussions on Filter bacteria conclude neatly in my usual 'generic fish' home!

....
David