Has Acara margarita been rediscovered?

[Willem Heijns]

Some of the names proposed by Heckel (1840) have become synonyms. One of them is Acara margarita, synonymized with Cichlasoma bimaculatum since Günther (1862). But in the latest issue of DCG-Info a report (Hablützel, 2011) is presented on a cichlid found in the Río Guaporé (Bolivia) which the author believes could concern Acara margarita. Good reason to take a closer look at this.

Heckel (1840) described Acara margarita from two specimens which were indeed caught (by Natterer) in the Río Guaporé. In a footnote he said that he suspected his new species to be identical to Perca bimaculata Bloch 1792. This is Bloch's picture :

Perca bimaculata by Bloch

perca.jpg (53.46 KiB) Viewed 869 times

Bloch did not have any fish at his disposal for his description. Instead he based his new species on a drawing used by Marcgravius (1648) when he described Acara brasiliensibus. That species looks like this:

marcgravius1648.jpg (48.42 KiB) Viewed 869 times

Both illustrations are not very accurate (note the position of the blotches on the body). Heckel was of the same opinion and therefore stated that both the name Perca bimaculata and Bloch's drawing were not usable ("unbrauchbar").

And here's the problem. Kullander (1983) believes that Acara margarita is therefore a replacement name (a nomen novum) for Perca bimaculata. But to which cichlid this name should be applied is not clear. Bloch only had a drawing (by Marcgravius) and gave "the rivers of Brazil" as locality. If Kullander is right the names Perca bimaculata and Acara margarita cannot be applied to any cichlid species at all, because they are impossible to identify. The type material consists of no more than an inaccurate drawing.
But Heckel only "suspected" Acara margarita to be identical with Perca bimaculata. In addition he gave an extensive and detailed description of Acara margarita. It would be a pity if such a description would also be rendered "not usable". Moreover, the cichlid recently found in the Río Guaporé nicely fits Heckel's description. Could it be Acara margarita after all?

Oh, and to which genus (Cichlasoma? Aequidens?) this species should now be assigned is quite a different matter. Maybe another topic….

[cichla]

Thanks, Willem, for publishing the interesting, historic pictures.
It is most likely that Heckel intended to describe a new species (here margarita) instead of introducing only a new name (nomen novum) for Bloch's Perca bimaculata. However, whether the species taxon name margarita is available for the species from the Guapore or not, depends on the rules and the articles of the code (ICZN) and not on what Heckel intended. So, I am not sure if Kullander is right to suppress the taxon margarita or not
Anyway, I agree with you Willem, that it would be a pity if such a nice name like 'margarita' would be treated as ''not usable''.

By the way, the species from the Guapore (now called Perlflecken-Cichlasoma) was occasionally collected. For instance, I think the Cichlasoma (collected by Staeck in the Guapore drainage) pictured in the Aqualog ''South American Cichlids III'' on page 22 (left column, labeled as 'Aequidens plagiozonatus') is the Perlflecken-Cichlasoma.

[Rico Morgenstern]

Thanks for bringing this up, Willem!

Unfortunately, the Code leaves much space for interpretation in this very special case.

new replacement name (nomen novum)
A name established expressly to replace an already established name. A nominal taxon
denoted by a new replacement name (nomen novum) has the same name-bearing type as the
nominal taxon denoted by the replaced name [Arts. 67.8, 72.7].

72.7. Name-bearing types of nominal species-group taxa denoted by new replacement names (nomina nova). If an author proposes a new species-group name expressly as a replacement (a nomen novum) for an earlier available one, then the two names are objective synonyms; both the nominal taxa they denote have the same name-bearing type despite any simultaneous restriction or application of the new replacement name (nomen novum) to particular specimens or any contrary designation of type, or any different taxonomic usage of the new replacement name.

In my view, Heckel's footnote and the fact, that he placed the older available name Perca bimaculata Bloch unambiguously in the synonymy of A. margarita, leave no doubt that he regards both as conspecific. The question is, does this render A. margarita, at least in part, a nomen novum, established expressly for the purpose to replace the, in Heckel's view inappropriate, name P. bimaculata? Hard to say, but if this is so, there would be no rescue for the beautiful name Acara margarita. The Guaporé specimens described by Heckel had no type status, the type(s) of A. margarita would be the same as for P. bimaculata, namely the now unidentifiable fish on which Marcgravius based his original drawing.

[Juan Artigas]

But the fact that Heckel (1840) placed Perca bimaculata unambiguously as a synonym of Acara margarita should not necessarily mean that that both descriptions are based in the same material. Heckel used specimens (three in the NMW collection?) that he unambiguously stated as collected by Natterer in Guapore River, even having a registration of the vernacular name Acará cascudo. While Blotch based the description on Marcgravius drawing. It is not established that Marcgravius drawing derives from the same specimens used by Heckel as syntypes as far as I can see. If my translation aid is giving me a right interpretation, Heckel just establishes in the footnote (as Willem puts it) his suspicious that it is the same fish. In this case, I don't see why Acara margarita as a name should not be valid? Even if demonstrated a synonym of Cichlasoma bimaculatum.

[Rico Morgenstern]

The specimens collected by Natterer are of course not the same as those on which Marcgravius' drawing is based. It may appear somewhat illogical because the description itself refers exclusively to the specimens collected by Natterer, however, by inclusion of P. bimaculata in the synonymy, Heckel based his species Acara margarita on both Natterer's and - by bibliographic reference - Marcgravius' specimen. Normally, all of them would together form the type series.
However, article 72.7 (quoted above in full) requires unfortunately that Natter's specimens have to be disregarded, if Acara margarita is considered a replacement name for Bloch's Perca bimaculata [which is not the same as Cichlasoma bimaculatum (Linnaeus, 1758) by the way]. Therefore, they have no syntype status and are not elegible for a lectotype designation. Acara margarita would then be in any case an objective junior synonym of Perca bimaculata Bloch (as is Sparus acara La Cepéde, 1802, another replacement name for the same), the true identity of which is currently not determinable.

Consequently, the name Cichlasoma margarita cannot be used as valid for the now 'rediscovered' fish, which must be described under a new name.

I don't see why Acara margarita as a name should not be valid? Even if demonstrated a synonym of Cichlasoma bimaculatum.

Juan Miguel, I am not sure what you try to say here? How could A. margarita be valid when considered the same as Cichlasoma bimaculatum, which is the oldest available name for any Cichlasoma species.

[Juan Artigas]

Juan Miguel, I am not sure what you try to say here? How could A. margarita be valid when considered the same as Cichlasoma bimaculatum, which is the oldest available name for any Cichlasoma species.

What I meant is available, valid name even if the species is not

[Juan Artigas]

It seems that Heckel got inadvertently trapped by the rules.

[Rico Morgenstern]

Yes, that's right. However, it remains a mystery what in the world has led him to identify Marcgravius' fish with these paricular specimens, as he recognized many different, but superficially similar Acara species, and his conclusion seems to be devoid of all the accuracy with which he described Natterer's cichlid collection.

[Willem Heijns]

Well, there's two compelling questions still bothering me.

1. Did Heckel really identify Acara margarita as being the same as Perca bimaculata?
In his footnote Heckel effectively disregards Bloch's description as not usable ("unbrauchbar"). Which leaves only his reference to Bloch. In a recent publication (Amado et al. 2011) Symphysodon haraldi was declared synonym of a yet to be described Symphysodon species. When I mentioned this, the reply I got was that this is merely a case of bibliographic reference, common usage in the old days. My guess would be Heckel did the same thing. In addition, the Code says that nomina nova need to be proposed "expressly as a replacement name". I don't believe Heckel did this.
If I'm right here, Acara margarita stands as an available and valid name.

2. Why hasn't anyone designated a neotype for Perca bimaculata?
If Acara margarita and Perca bimaculata are the same, the type of Perca bimaculata (the oldest and thus valid name) would be the drawing by Marcgravius that was used by Bloch in his description. This type is apparently lost. Reason enough to designate a neotype. Still, Kullander (1983) states that this is not possible. He writes: "the Code does not allow a neotype to be designated for the arbitrary application of the name margarita to either species in question". I think he is right. But why not designate a neotype for Perca bimaculata?
If this were to be done, Perca bimaculata would become a valid name (maybe even applicable to the rediscovered Guaporé specimens). With current generic assignments we would then have another interesting problem at hand.

[Juan Artigas]

1. Did Heckel really identify Acara margarita as being the same as Perca bimaculata?

Heckel lists Perca bimaculata just below the proposed new species name Acara margarita, this is the then common way to declare synonymy I believe, although he does not mentions as much as I can see that it is a replacement name I agree. But, how else could that be interpreted?

2. Why hasn't anyone designated a neotype for Perca bimaculata?

We just have Heckel's unsupported opinion, and a bad drawing, so, how can we be sure that Bloch was actually describing the Guapore cichlid? Heckel was, but his types it seems can not be used. So, a neotype for what?

[Willem Heijns]

I would interpret it as a bibliographic reference without consequences for nomenclature.

The type of Perca bimaculata is not the "bad drawing" as you call it, which I published in the first post. The type is the drawing Bloch used to make his description. The drawing made by Marcgravius. This latter drawing is lost, although Heckel saw a copy of it (as he mentioned in his footnote).
We can be pretty sure the fish described by Marcgravius did not come from the Guaporé (see Kullander (1983) for an explanation). But that is not relevant for the nomenclatural issue. Again, if Acara margarita and Perca bimaculata are one and the same species, we could pick one of the Guaporé specimens as neotype.

[Juan Artigas]

I would interpret it as a bibliographic reference without consequences for nomenclature.

A bibliographic reference mentioning another species just below the declaration of a new species name? What would be the purpose of it?

The type of Perca bimaculata is not the "bad drawing" as you call it, which I published in the first post. The type is the drawing Bloch used to make his description. The drawing made by Marcgravius. This latter drawing is lost, although Heckel saw a copy of it (as he mentioned in his footnote).

We can be pretty sure the fish described by Marcgravius did not come from the Guaporé (see Kullander (1983) for an explanation). But that is not relevant for the nomenclatural issue. Again, if Acara margarita and Perca bimaculata are one and the same species, we could pick one of the Guaporé specimens as neotype.

If Marcgravius drawing is lost, wouldn't that make it possible that Nattered collected syntypes at NMW be declared as neotypes for Perca bimaculata? If I understand it correctly, we can not be sure Acara margarita and Perca bimaculata are one and the same species. What would be the reason to name a neotype for Perca bimaculata, whose origin we don't know and whose type is lost (and then unidentifiable except for Heckel's unsupported opinion) in a fish recently collected from the Guaporé? In this case Acara margarita syntypes are irrelevant (even if the same species as the recently collected cichlid) because the types can not be legally used.

[Willem Heijns]

We can only guess what the purpose of Heckel was in mentioning Perca bimaculata. But then, purposes and intentions don't count.

It would certainly be possible to designate one of Natterer's Guaporé cichlids as neotype for Perca bimaculata. But only if the two names (bimaculata and margarita) would refer to only one species. The reason would be that the name Perca bimaculata is available and valid and the type is lost.

Should the two names refer to two different species, designating a neotype for Perca bimaculata would serve no real purpose, since Perca bimaculata cannot be identified. In this case the two fishes used by Heckel to describe Acara margarita would be syntypes.

[cichla]

Acara margarita: I am afraid that Kullander might right to treat Heckel's margarita as ''not usable'' (see Rico's notes above). On the other hand I would like to treat Heckel's statements about Perca bimaculata just as a 'bibliographic reference' (see Willem's contribution above). However, it seems that Heckel is indeed „inadvertently trapped by the rules.“ (see Juan above).

Perca bimaculata Bloch is treated as ''species inquirendae'' by Kullander (1983, 2003). I dont agree with that because all authors after Bloch treat it as a (what we call now) Cichlid fish species. And later always as a Cichlasoma. Since there is already a Cichlasoma bimaculatum (Linnaeus) it needs a ''replacement name''. The oldest available one is Sparus acara Lacepède.

In the similar case of Perca brasiliensis Bloch, Kullander (1982) used the taxon as available for a Crenicichla of the saxatlis group from North-East Brazil http://www.dcg-online.de/encyclopedia/w ... indler.pdf Why not using Perca bimaculata (then Cichlasoma acara) for the Cichlasoma from Pernambuco?

It would certainly be possible to designate one of Natterer's Guaporé cichlids as neotype for Perca bimaculata. But only if the two names (bimaculata and margarita) would refer to only one species. The reason would be that the name Perca bimaculata is available and valid and the type is lost.

Since the type locality of Perca bimaculata is North-East Brazil (most likely Pernambuco) I dont think that it is reasonable to use a specimen of Heckel's margarita as a neotype for it. If Acara margarita is treated as a available (usable) taxon name (as the majority of all authors did, until Kullander 1983) then the type locality of this species is the Rio Guapore and the scientific name of the Perlflecken-Cichlasoma would be Cichlasoma margarita.

[Willem Heijns]

Ingo, could you elaborate a bit on the term "species inquirendae"? It is not a formal term in the sense of the Code, but what does it (formally) mean?

I would be interested in the description of Sparus acara Lacepède and why it is believed that this is the same species as Bloch's Perca bimaculata.

The difference in treatment of Perca bimaculata and Perca brasiliensis is of course that for the latter species no replacement name has been proposed (as far as I know). Heckel's work causes the problems here.

Although Bloch (1792) gave "the rivers of Brazil" as locality for Perca bimaculata, it is widely assumed that this species comes from north-eastern Brazil (Kullander, 1983). Having said that, it is quite impossible that Perca bimaculata is the same species as Acara margarita, taxonomically speaking. This could very well be a reason to undo Heckel's "proposal" for the replacement name and treat Acara margarita as a valid name. Or is this wishful thinking?

Finally, which Cichlasoma species from Pernambuco are you referring to, Ingo?

[cichla]

Ingo, could you elaborate a bit on the term "species inquirendae"?

Yes, sure....
Lincoln et al. (1998: 280): „species inquirendae: meaning a species to be queried; an incompletely defined species that requires further clarification or characterization“

I would be interested in the description of Sparus acara Lacepède and why it is believed that this is the same species as Bloch's Perca bimaculata.

There is no description at all, just the name Sparus acara and a statement that this is the new taxon name (''replacement name'') for Bloch's Perca bimaculata.

The difference in treatment of Perca bimaculata and Perca brasiliensis is of course that for the latter species no replacement name has been proposed (as far as I know). Heckel's work causes the problems here.

The taxonomic decision whether Bloch's species Perca bimaculata (= Sparus acara) is used for the Cichlasoma from Pernambuco or not has nothing to do with the proposed replacement name. The taxonomy and the nomenclature are independent. It is a (somewhat) subjective decision by Kullander whether Bloch's taxa are treated as available (Perca brasiliensis = Crenicichla brasiliensis) or as 'not usable' (case Perca bimaculata).

Finally, which Cichlasoma species from Pernambuco are you referring to.

see here: http://www.dcg-online.de/encyclopedia/w ... indler.pdf

At the time of Marcgravius (1648) the city Recife was called Pernambuco. So, I should clarify that the possible type locality 'Pernambuco' is referring to the area of Recife and does not mean the Brazilian state Pernambuco.

[Rico Morgenstern]

1. Did Heckel really identify Acara margarita as being the same as Perca bimaculata?
In his footnote Heckel effectively disregards Bloch's description as not usable ("unbrauchbar"). Which leaves only his reference to Bloch. In a recent publication (Amado et al. 2011) Symphysodon haraldi was declared synonym of a yet to be described Symphysodon species. When I mentioned this, the reply I got was that this is merely a case of bibliographic reference, common usage in the old days. My guess would be Heckel did the same thing. In addition, the Code says that nomina nova need to be proposed "expressly as a replacement name". I don't believe Heckel did this.
If I'm right here, Acara margarita stands as an available and valid name.

I do not agree that we have a mere 'bibliographic reference' here. The entry in the synonymy refers to the publication in which Perca bimaculata was made available by Bloch and not to a subsequent use of the name. Furthermore, Heckel (1840: 338-339) wrote in the footnote: "Without the courtesy of Hr. Prof. Lichtenstein of Berlin, who had te kindness to send me an exact copy of the original drawings contained in the rich collection of Prince Moritz von Nassau, it would have been impossible to recognize in the Perca bimaculata Bloch our Acara margarita[...]" (my translation). This leaves no doubt that Heckel accepts the conspecificity of the specimens described by himself with Bloch's P. bimaculata, i. e. proposed a synonymy, instead of using the latter name as a reference to some subsequent misidentification of specimens referrable to A. margarita. A possible explanation why Heckel created a new name instead of calling the species Acara bimaculata (Bloch) is the supposed inappropriateness of the name. Be that as it may, in any case Heckel proposed a new name wich replaced an older available one.

2. Why hasn't anyone designated a neotype for Perca bimaculata?
If Acara margarita and Perca bimaculata are the same, the type of Perca bimaculata (the oldest and thus valid name) would be the drawing by Marcgravius that was used by Bloch in his description. This type is apparently lost. Reason enough to designate a neotype. Still, Kullander (1983) states that this is not possible. He writes: "the Code does not allow a neotype to be designated for the arbitrary application of the name margarita to either species in question". I think he is right. But why not designate a neotype for Perca bimaculata?
If this were to be done, Perca bimaculata would become a valid name (maybe even applicable to the rediscovered Guaporé specimens). With current generic assignments we would then have another interesting problem at hand.

This question was already answered by Kullander (1983).
The type(s) of Perca bimaculata (and, by virtue of Article 72.7, also of Sparus acara and Acara margarita) is (are) the specimen(s) on which Marcgravius based his original drawing (not the drawing itself). I was not so far able to check Kullander's sources (mostly Marcgravius 1648 and Whitehead 1973), however, if his conclusions about the possible origin of Marcgravius' freshwater fishes are right, there are several species to come into consideration (e.g. Cichlasoma orientale, C. santifransiscense and perhaps one or more undescribed forms). Therefore, as long no evidence is presented that allows a further restriction of the type locality or an identification with one of the species by certain characters, any neotype designation would apply the name(s) arbitrary to one of this forms. Furthermore, a neotype designation is a more than delicate issue because of all the rigid requirements specified in Article 75.3. In any case, It would be a nomenclatorical tightrope walk, and thus it would perhaps create more problems than it can solve. Additionally, Perca bimaculata Bloch, 1792 cannot gain validity in the genus Cichlasoma for it would be a junior homonym of C. bimaculatum (Linnaeus, 1758), and the next available name, Sparus acara, has virtually never been used (not even as a synonym). Let's face it, would it be worth all the efforts to save such a name?

[cichla]

Sparus acara is used by Cuvier & Valenciennes and other authors.
I agree with you Rico, nevertheless Perca bimaculata Bloch is an available taxon which was always treated as a Cichlasoma. It is pretty unlikely that the specimen (type) pictured by Marcgravius (1648) is conspecific with C. santifransiscense, because this species is distributed in the Rio Sao Francisco (and smaller drainages south of the mouth), but with the Cichlasoma from Recife (then Pernambuco). Kullander used Perca brasiliensis for a Crenicichla from the Sao Francisco, but this is also not conspecific with the saxatilis-like species from Recife. For authors it seems more profitable to create new names instead of using (protecting) old, historic, taxonomically available names. This is the tragedy.

[Willem Heijns]

It's very easy to get lost in complicated discussion like this. I think a brief historic summary may help us.

1648:
Marcgravius describes Acara brasiliensibus. Whether he had real fish at his disposal or only the drawing provided to him by Prince Moritz (I knew there was a Dutch tie in there ) is not clear. He did publish a woodgraving of his new species. There were no rules in force governing publications, new names, types, etc.

1792:
Bloch describes Perca bimaculata using Marcgravius' description (with woodgraving) of Acara brasiliensibus and the drawing made by Prince Moritz. He had no real fish to look at. His description also contains a (very inaccurate) drawing. According to the Code (which governs nomenclature as of 1758), the drawing by Prince Moritz is the name-bearing type. The type locality is "the rivers of Brazil".

1802:
Lacepède lists Sparus acara as a replacement name for Perca bimaculata.

1840:
Heckel describes Acara margarita, inadvertently proposing it as a replacement name for Perca bimaculata.

So we have two replacement names for Perca bimaculata. Following the Code, replacement names and the name(s) they replace become each other's objective synonyms. And according to the Principle of Priority the oldest available name of those synonyms becomes the valid name. Nomenclaturally, our species thus bears the name Perca bimaculata Bloch 1792; type: a drawing by Prince Moritz, now lost); type locality: the rivers of Brazil.

When it comes to taxonomy, it's a quite different matter. It is assumed that Marcgravius collected his fish in the area of Pernambuco, although Bloch expanded that range to "rivers of Brazil". If the above assumption is correct, Heckel's Acara margarita simply cannot be identical with Perca bimaculata. Heckel was wrong. Consequently, the species from the Río Guaporé has no available name to apply to it.
As for the identity of Perca bimaculata, it has been suggested (Schindler, 1995) that this species is the same as Cichlasoma orientale Kullander 1983. If this is correct, Cichlasoma orientale becomes a synonym of Perca bimaculata. Assigning this name to Cichlasoma would create a homonym (Labrus bimaculatus is now Cichlasoma bimaculatum), so the next available name has to be applied. That would be Sparus acara, rendering Cichlasoma orientale a synonym of Cichlasoma acara (Lacepède 1802). We would still need a neotype for it and to designate a type locality.
I wonder what Kullander would say to all this....

@ Rico: I stil have my doubts about Heckel. He did not say that he recognized his Acara margarita to be Perca bimaculata; he merely suspected it (ahnen = to suspect).

@Rico: the type of Perca bimaculata cannot be the specimens (if any) Marcgravius might have used. In 1648 there were no rules governing this. The Code stretches its influence back to 1758 and of publications before that date only the information (names and descriptions) could be used (article 3.2). Therefore the type can only be associated with the first publication after 1758 and thas is Bloch (1792). He used a drawing (made by Prince Moritz), so that drawing is the type.

@Ingo: the term "species inquirendae" apparently has no nomenclatural status. Or am I missing something?

Finally, a general question: what is the use of publishing replacement names if they disappear into (objective) synonymy?

[Juan Artigas]

Willem, thanks for the comprehensive summary, things start to clear up. I just have one question. What is the version of the code we are assuming rules on those nomenclature acts?