What is the L# designated for this pleco?

[Vicz24]

I have had this guy since he was very small & is now 10" long. The Marble Sailfin Pleco is L001 but what is the Leopard Sailfin Pleco's L#? I am having a hard time finding it.



Thank you.

[pleco_breeder]

Have a look at L83/L165 ;)

Larry

[Vicz24]

That looks like the one, thank you. No wonder I had a hard time finding it, the first picture looks like the pleco is almost red & is a juvie.

[racoll]

This is not L083 or L165, it is

Pterygoplichthys gibbiceps

.

Those L numbers apply to specific, local populations of that species, not automatically to all members of P. gibbiceps.

[pleco_breeder]

Without trying to hijack the post, this may be a good time to find out if I missed something in regards to L's. My understanding has always been they are names applied to a fish till it is described to species. This is where it becomes a grey area for me. Since both L's have been recognized as this species, wouldn't collection locality, within the range of the species, deem them all to be the same? It only makes sense to me if there is a biological difference enough to segregate them, wouldn't that same difference also segregate them from the species?

I know, devils advocate and all that, but this does seem to be a valid question.

Larry

[Jools]

How's your intuitive set theory?

All wild species are made of up populations. Some with very narrow and some with very large distributions. The L numbers apply to specific populations in this case (sometimes they do, sometimes they don't). So, L083 for example, is a sub set of

Pterygoplichthys gibbiceps

and all P. gibbiceps cannot be said to = L083.

This is where it becomes a grey area for me. Since both L's have been recognized as this species, wouldn't collection locality, within the range of the species, deem them all to be the same?

Yes in this case but not always - they may be biologically distinct (example

L200

). They may also be without the known or originally described range.

It only makes sense to me if there is a biological difference enough to segregate them, wouldn't that same difference also segregate them from the species?

Yes. But that's not what happened here. The l-numbers were created, from a few collected fish, and once they were looked at in detail it was found that they were already a described species. The l-number persists as, as has happened here, folks aren't too sure what they really mean (oh, and L083 is commercially sexier and easier to spell than Pterygoplichthys gibbiceps).

Jools

[pleco_breeder]

In this case, since the number stays because of collection locality, what is the difference which separates it from its own species?

I know from conversation the number L083 has been applied to tens of thousands of fish labeled "marble sailfin pleco" prior to reaching the wholesale level and shipped all over the world. Therefore, there has to be some way of differentiating the population from the species. Otherwise, which name is applied no longer becomes relevant because the population is mixed.

With that being the case, I suggest we place both the nomenclature and number in synonymy and go with the more popular "big spotted suckyfish". Of course this can't be confused with the "big-spotted suckyfish" or else we're back at square one.

Larry

[Jools]

In this case, since the number stays because of collection locality, what is the difference which separates it from its own species?

The number is retired, it doesn't "stay". Unless, of course, in the future someone revises the species and find out all the population in the Tefe is something else. However, as you're about to say, it is perpetuated incorrectly and, in many cases, for commercial gain.

I know from conversation the number L083 has been applied to tens of thousands of fish labeled "marble sailfin pleco" prior to reaching the wholesale level and shipped all over the world. Therefore, there has to be some way of differentiating the population from the species. Otherwise, which name is applied no longer becomes relevant because the population is mixed.

Are you really saying tens of thousands of P. gibbiceps are exported from S America? The name is not correct if the fish didn't originate from the locality but it's still a retired l-number...

With that being the case, I suggest we place both the nomenclature and number in synonymy and go with the more popular "big spotted suckyfish". Of course this can't be confused with the "big-spotted suckyfish" or else we're back at square one.

Ah, but then how do we tell it from the mega spotted suckyfish?

Jools

[2wheelsx2]

I know this is getting nitpicky into the semantics, but if the L number is only for the fish collected in a locality, then what happens to the F1? Say you bred L24, you should not technically be selling them as L24 F1 since there's no such thing. You'd have to say unclassified Pseudacanthicus species bred from wild caught L24, wouldn't you? Seems like a vicious circle to me.

[pleco_breeder]

Are you really saying tens of thousands of P. gibbiceps are exported from S America? The name is not correct if the fish didn't originate from the locality but it's still a retired l-number...

One farm in the US that I'm aware of sales pond raised stock of these globally via a jobber. I used to have a working relationship with the individual, via their wholesale entity, and obviously discussed plecos in depth quite often. Anyway, it was his common practice to place an L number on any fish if one was available that matched the fish. I didn't, and still don't, condone the practice, but I'm sure it is still happening. Likewise, I probably bought hundreds of L129/Hypancistrus furunculus just because he had marketed them under the name mega clown pleco waiting on a real one. Of course this was long before the fish actually became available and was still on a holy grail list of fish to have.

Larry

[Mike_Noren]

Just in case people are not aware of this: L-numbers are not scientific. L-numbers are placeholder names used by the German aquarist magazine Die Aquarien und Terrarienzeitschrift (DATZ) to get around the problem that there are so many undescribed (i.e. unknown to science and does not have a scientific name) loricariids being exported from South America. Every shipment of fish which to the people of DATZ look different from previous batches get a new L-number.

Once the species has a scientific name the L-number is retired.

There's not a 1:1 relationship between L-numbers and specific names. Sometimes it turns out the people of DATZ have lumped several named species under one L-number; sometimes they've put several L-numbers on a single named species.

[pleco_breeder]

I know this is getting nitpicky into the semantics, but if the L number is only for the fish collected in a locality, then what happens to the F1? Say you bred L24, you should not technically be selling them as L24 F1 since there's no such thing. You'd have to say unclassified Pseudacanthicus species bred from wild caught L24, wouldn't you? Seems like a vicious circle to me.

Technically, since you bred fish from that locality, F-1 L24 would still be correct provided the adults were both from that locality.

My concern, and I didn't even realize this till this thread, is the question of whether there is a difference. L333 demonstrates this very well by the different morphs sold under the same moniker. All of them were initially sold under the same name when the number was first placed. I have to say I was rather upset with the quality of the first L333 alenquer, now L401, I received because they didn't match the standards I had came to expect of the fish. All the same, the first L333 "Porto do Moz" were so spectacular I spent months trying to figure out what had been sent me because they couldn't be L333. There are definable traits to base this on.

I can definitely understand the idea of breeding like fish to continue their traits, and even specific localities if they have a defining trait to distinguish them from the rest of the population. However, I can see no viable reason, aside from commercial gain, to continue to segregate the retired L83 from P. gibbiceps even if it is just a common name.

I completely agree with no longer using described numbers since the species description is always going to be more in depth than a picture in a magazine with the subtitle "new from Brazil". However, my point is if the number really is descriptive of a race or locality enough to differentiate it from the species it is thought to belong to, is it really retired. In the case of P. gibbiceps, I personally believe it's just a synonymous common name used strictly for commercial gain because numbers seem to directly correlate with money. I'm simply hoping someone can explain to me the difference since my own understanding of nomenclature and the generally accepted L format would indicate L083 and P. gibbiceps are the same.

If a fish inhabits a large area, and is scientifically accepted to inhabit that area without barriers forcing evolution, and free movement to intermingle with other variants of the species, why would fish within a small section of that range be defined as anything different than the rest of the species?

Larry

[Vicz24]

Wow, look what I started..lol. This is very informitive indeed & sometimes confusing. The L# used in the hobby for selling I believe is used for simplicity more than $ as it is easier to remember the L# of a pleco rather than the scientific name. You certanly can not go by the common name people have on a pleco as alot don't have one like L205. With plecos like L201 they are mistaken for alot of other plecos using the common name such as "Gold spot", "Gold Inspector", "Galaxy","Vampire" & so on. The only real way to tell a pleco is do the research & ask questions on knowlagable sites such as this one which is what I was doing with my pleco as I couldn't find it in the list, just the L001.

[racoll]

I completely agree with no longer using described numbers since the species description is always going to be more in depth than a picture in a magazine with the subtitle "new from Brazil". However, my point is if the number really is descriptive of a race or locality enough to differentiate it from the species it is thought to belong to, is it really retired. In the case of P. gibbiceps, I personally believe it's just a synonymous common name used strictly for commercial gain because numbers seem to directly correlate with money. I'm simply hoping someone can explain to me the difference since my own understanding of nomenclature and the generally accepted L format would indicate L083 and P. gibbiceps are the same.

If a fish inhabits a large area, and is scientifically accepted to inhabit that area without barriers forcing evolution, and free movement to intermingle with other variants of the species, why would fish within a small section of that range be defined as anything different than the rest of the species?

Really interesting points Larry. I agree it isn't always clear cut. I think there is retiring L numbers, and retiring L numbers, and they're not necessarily the same process.

First case in point: take

Peckoltia compta

, a species "discovered" and traded as L134 well before it was described to science. This is a simple case of the species being described from a relatively localised area that matched the trade collection localities, and the L number was retired and just used as a common name. Simple.

Now, take the case of L083 and P. gibbiceps, it is somewhat different. Pterygoplichthys gibbiceps was described in 1854 from the upper Negro, obviously long before the ornamental fish trade started. L083 was a fish "discovered" in the 1990s from the Xingu, and it looks quite different to the Negro P. gibbiceps, that was later given the number L165 (although I'm not sure why, as it was already described from the same river, but I accept that there could be multiple forms in the Negro). What we know as P. gibbiceps is widespread, and many other forms are also found in South America, and someone made the call that all of these represented one species. I don't know whether that was based on scientific assessment or not, but I wouldn't be at all surprised if "P. gibbiceps" was in fact a complex of species.

Anyway, my point is in this situation, that retiring this L number (L083) is indeed a somewhat subjective decision, until such a time that scientists get round to dealing with the problem. If it were my decision, I would probably use Pterygoplichthys sp. "L083" for the Xingu population/species, seeing as it's distinctive enough.

[Mike_Noren]

I would probably use Pterygoplichthys sp. "L083" for the Xingu population/species, seeing as it's distinctive enough.

That's a taxonomical statement that this is a distinct but as yet unidentified or unnamed species. If you want to express that this is a distinct population of a named species you could write Pterygoplichthys gibbiceps "L83". Perhaps even better would be Pterygoplichthys gibbiceps "Xingu", as that is more informative than the L-number.

In my opinion it's never wrong to use the most specific alternative, especially if you suspect that gibbiceps from capture locality X are not the same species as gibbiceps from capture locality Y.

[racoll]

That's a taxonomical statement that this is a distinct but as yet unidentified or unnamed species. If you want to express that this is a distinct population of a named species you could write Pterygoplichthys gibbiceps "L83". Perhaps even better would be Pterygoplichthys gibbiceps "Xingu", as that is more informative than the L-number.

In my opinion it's never wrong to use the most specific alternative, especially if you suspect that gibbiceps from capture locality X are not the same species as gibbiceps from capture locality Y.

I agree, and how about Pterygoplichthys cf. gibbiceps "L083 Xingu" for information!

However, I was thinking more in terms of PC's formal cat-elog nomenclature, which doesn't and probably shouldn't incorporate such a name.

[Jools]

SPECIES != L-NUMBER

So, I think the thing here is that we have to understand that the l-number systems isn't anything like the linnean system. That may be the understatement of the century.

While a species is different from the next species due to characteristics, this is not true of l-numbers. An l-number can be created for a multitude of other reasons. One reason for creating a l-no is that the l-no in question is from a different river than the type locality of a species it otherwise matches. So, L083 can only come from the Xingu, it's what, in that instance, is behind the creation of the number. That's got nothing to do with the scientific description of P. gibbiceps as Mike points out.

L083 falls within what I'm happy to call

Pterygoplichthys gibbiceps

, but I would not say that L083 (as "described" by a photograph and some words) is enough to say it's not what I'm happy to call

Pterygoplichthys gibbiceps

. L-numbers are within the serious aquarists domain, I can make those calls, I wouldn't dream of being so bold in the linnean world.

Consider L075, L124 and the other one I forget right now but it's up in the 300s. They're all

Peckoltia sabaji

(as far as I'm concerned) but only L075 is from the lower Para...

It's not simple...

Jools

[Shane]

I am biting my tongue not to jump into this thread, but I am pleased to see that my years of questioning the utility of L Numbers are starting to look (to some) more like prescience than lunacy.

L Numbers are NOT a useful non-scientific identification system. They are a marketing gimmick developed by an aquarium magazine to sell copy. They have since become a marketing gimmick for several book publishers, exporters, importers, retailers, hobbyist breeders, and convention organizers. I can sell the fish I breed at one of my local clubs by their proper scientific name or I can put their L Number on the bag and get twice as much.

Pterygoplichthys gibbiceps

Rio Xingu poplation is a perfect description, but L83 will sell for more money.

Take a look through the For Sale sale threads if you don't believe me. Dozens of postings selling L46 but almost none selling

Hypancistrus zebra

. 21 years after description and the "retired" L Number is used more often than either the scientific name or common name.

-Shane

[pleco_breeder]

Not to make light of this, as I do now believe this is one of the major flaws of the L system, but I think we've stumbled into a killifish collectors worst nightmare with an undefined number system.

I'm no ichthyologist, and gave up on most of those studies long ago. However, I can agree with the Xingu modifier for P. gibbiceps based on the range of the species and potential for multiple species. I simply hadn't given consideration that a species over a century since description hadn't been reviewed well enough to potentially revise. I find that even more surprising since it hasn't been that long since Glyptoperichthys and Pterygoplichthyes (I know something is misspelled there, but can't find it) were revised and segregated. Of course, most of those works are conducted from museum/educational holdings and not necessarily a sample of the various areas of the species range.

Anyone please feel free to correct me if I'm wrong in this statement, but it appears this becomes a question of "lumpers" vs. "splitters". I would still be interested to know what the defining difference of the Xingu population is. Note that I do not use the L number ;)

Larry

[racoll]

I can sell the fish I breed at one of my local clubs by their proper scientific name or I can put their L Number on the bag and get twice as much.

21 years after description and the "retired" L Number is used more often than either the scientific name or common name.

I don't think hobbyist's reluctance to use scientific names, or the fact that they are often seduced by creative advertising, has anything to do with the utility of an interim taxonomic system based on an iconotype-like system. The two are separate to me.

[racoll]

SPECIES != L-NUMBER

Well, it could be argued that DESCRIBED SPECIES != SPECIES ...

it appears this becomes a question of "lumpers" vs. "splitters"

Taxonomy as generally conducted has a strong tendency to underestimate biodiversity (species richness). Therefore, the L number system with it's "oversplitting" may ultimately be closer to the mark (averaged out of course).

[pleco_breeder]

As an active breeder, I have to believe Shane is right about this one. For some reason, I don't know what it is, pleco hobbyists are drawn to numbers. So many common names have been applied to these fish, and a lot of mis-identification with those, most hobbyists are afraid to buy something that hasn't been defined by somebody. Even with the simple ID of Hypancistrus zebra, and the simple zebra pleco common name, it's use is avoided as if L46 is some magic number that all of a sudden makes it more real.

This even happens with common Ancistrus strains. L34= Ancistrus ranunculus= flathead bristlenose. L144 is more valuable than blue eye gold Ancistrus even after explaining that the true L144 is not commercially available, and this is a morph of a common Ancistrus.

To make things even more confusing, on the rare occasion I see the correct fish offered, L107 and L184 are usually listed as "L107/L184" thereby removing any chance of knowing the locality and only hoping they are in fact the same species prior to a description. I've seen the same thing done for L399 and L400. This seems to be a habit which could lead to a lot of hybrids in the hobby and I've brought this up in the past in a different context.

The system is without a doubt flawed, and everybody from collectors to hobbyists have made it worse, but these numbers have become so entrenched in the hobby it would be impossible to fix. I believe a lot of the problem lies in human nature to want what is new. If it has been around enough to be described by science, that normally isn't the case. However, if it's completely unknown to science, and can only be defined by a catalog system while it awaits recognition, it must be really special.

This even happens in the case of recently discovered/described species, but normally fizzles rather quickly. Good recent examples in the hobby would be Danio margaritatus and Oryzias woworae. Both were described in the same approximate time frame they became available in the hobby. Both had OUTRAGEOUS initial asking prices, but rapidly fell to reasonably affordable. I don't believe the price drop was completely because of breeders making them available, but they were no longer "new".

In the pleco world, there are a lot of difficult breeding fish, but there are also a lot which are very simple. The mentality of being rare, even with fish which are easily reproduced in large quantities, drives the price. In the case of some easily produced fish, the perception of being rare and still easy to breed opens a completely different market for them as the "gold diggers" begin looking for them to make a fast buck.

I am not referring to any specific individual when using the phrase "gold digger". This is what I call anyone who keeps plecos only for the sake of cashing in on a market niche. I think everybody knows somebody who plans to turn these fish into their income source for an early retirement and has no real interest in them past that. I will also add the disclaimer, for Jools sake, that Planetcatfish most likely does not endorse this, or any of my comments.

Larry

[Mike_Noren]

I can sell the fish I breed at one of my local clubs by their proper scientific name or I can put their L Number on the bag and get twice as much.

This goes for all types of common names: any fish is much easier to sell under a common name than under its scientific name. I actually did a little experiment a couple of years ago at an aquarium auction, I sold some fish as "Tilapia snyderae" and some as "Rust tilapia (Tilapia snyderae)". Take a wild guess which sold and which didn't.

Latin names are intimidating and difficult to pronounce. Common names (which is what L-numbers really are) are not.

[AndrewC]

Latin names are intimidating and difficult to pronounce. Common names (which is what L-numbers really are) are not.

It's not all about money, Mike couldn't have said it better.

[Shane]

Common names (which is what L-numbers really are) are not.

I agree with you that L Numbers are, at best, just common names. If one accepts this then one also accepts that L442 is a designation equal in utility to Big White Spot Rubbernose pleco and nothing more.

The suppossed locality designation associated with L Numbers would be really useful if it were true, but the vast majority of L Numbers issued have only very vague locality data associated with them at best and wrong information in dozens of cases. I remember very clearly several Colombian exporters being very upset when a series of Orinoco fish were issued L Numbers as Venezuelan fish.

The system might have been far more useful if we called the fish Chaetostoma sp 10° 00' 00" N 66° 58' 08" W instead of L 187.
-Shane