Parosphromenus spec. “TCE 2015”

[David Jones]

[quote=”Stefanie” post=5135]…(I never had P. tweediei – but the day may come 😉 ). [/quote]

I hope you do get them soon – actual tweediei are real beautiful fish! (but still not sure what these are :unsure:). I just got 7 F! tweediei juvies so am excited to see what they develop into 🙂

[David Jones]

Here is a video of the spawning sequence, same as the photos above. This pair does not make a bubble nest and the male removes all eggs during spawning to be reared under a leaf. Notice how the female can both swivel and rotate her eyes, like some kind of mechanical submersible vehicle – something I had not really noticed until making this video. The video was filmed at 50% speed to allow for very smooth observation. Be sure to watch in HD. It is a joy to photo and video them and share on this forum 🙂

https://youtu.be/SzpR88PUg4k

[Peter Finke]

In your fine video the fish look less similar to P. spec. Parengean resp. spec. Palangan, and more like tweediei with much blue in the anal fin. The red in the female unparired fins ist typical for female tweediei in courtship colours.

[David Jones]

Peter, these are not the P. spec. Parengean / spec. Palangan obtained by the importer in Florida. These are the more recent import via The Cichlid Exchange which share, as you say, many characteristics similar to P. tweediei.

At times I have wondered if they could be more P. alfredi? They do not have whitish-blue pelvic fins mentioned in the account for that species, but instead the blue-green/black pelvic fins of tweediei.

Or P. rubrimontis? They do not have the elongated, pointed dorsal fin tip as mentioned in the account for that species, but a rather the less extended dorsal fin tip characteristic of P. tweediei.

Or P. opallios? They do not have the blue-colored, spotted ventrals [pelvic fins] (similar to P. nagyi) with light blue filaments mentioned in the account for that species, but the pelvic fins colored as for P. tweediei, as already mentioned.

Or P. phoenicurus? They do not show the classic rhombic caudal fin shape and coloration of the wild-caught P. phoenicurus, but show shape and coloration more closely similar to P. tweediei.

I could make no conclusive judgements based on the unpaired fin spine/ray counts mentioned in the species accounts, as the counts mostly overlap in their variations. From what I could count from the photographs these fish could be any of the four species (possibly), but are not excluded as P. tweediei, based on those counts.

So based on:

• Male fin color and shape.
• Fin spine/ray counts.
• Female body and fin coloration.
• The fact that TCE also had imported P. nagyi from Malaysia at the same time this fish was imported and P. tweediei also come from Malaysia (empirical, not conclusive, evidence).
• The fact that P. tweediei is still to be found in the wild (as of Dec. 2014), even in the much altered (but more easily accessible) habitats of the palm plantations.
• That fairly recent imports in the trade (Helene’s fishes that also share many if not all of the characteristics of P. tweediei) could also be P. tweediei and indicate their ongoing accessibility to exporters. (versus P. phoenicurus – only one known commercial import from only one known collection location. P. opallios, on the other hand, has had more frequent exportations in the trade i.e. TCE 2013 and possibly again this year, listed by the same vendor, but unverified).

We have some body of facts pointing to these fish being more likely P. tweediei (or some close variant) than any of the other closely related forms.

In all of this, I think your observations in comments #4039 and #4047 of Helen’s thread “help with id ? alfredi ? tweediei ? rubrimontis?” should be well considered, as they place our questions and potential answers within the proper biological/ecological situation when it comes to the taxonomy of this genus.

I want to know what “species” this fish is and give it a biological name. However, given the limited nature of the binomial naming system seeking to be imposed, as Peter says, upon the fluid and ever-changing flow of biological life, and all of the vast uncertainty of the phylogenetic relationships of the relatively sparsely collected and documented forms of the genus, I am realizing any name we give this fish is likely to be temporary, subject to ongoing change and serves only as a reference point from which to talk about the actual fish. Add to this the changes that come into play once the fish is removed from the natural environment and begun to be propagated within the wholly different “habitat” of the aquariums of the fishkeepers, including the possibility of hybridization, genetic bottleneck (inbreeding) and completely different nutritional inputs – we can already see changes in color and body shape of captive-bred populations compared to the original wild forms. Lastly, in most of the species accounts on this website, there are the recurring provisos to the descriptions of each species of this closely related group, that there is quite a lot of color variations, among the wild collected fish and in their captive offspring. So the best we can do, in the absence of clear, known characteristics, known collection locations or especially the more certain genetic studies, is to make close observations of as many of the characteristics of the fish we have based on the available knowledge and to try to compare as many known facts as we can to seek some greater clarity about the forms we have. That is why this forum, with everyone’s contributions is so valuable in that regard, and this is exactly what is taking place in the comments and observations that have been made by everyone to best degree.

[Peter Finke]

Dear David, I fully agree with you; we cannot exclude all these species, and I add: We cannot exclude something else. What we learned from the “Mimbon 98”-case was: Most similar to alfredi, but possibly a very similar variant. Without any reliable informations on the location we are bound to keep silent on this question. We can surely exclude phoenicurus, for wild phoenicurus always had this slightly elongated caudal. (They lost this feature in the secnd or third filial generation, indicating that possibly phoenicurus is still veryay near to tweediei. More we are unable to say).

I understand your interest in giving the beautiful fish a name, but we can’t. We can only observe and describe the fish in all behavioural situations as acutely and most differentiated as possible, and you do so. That’s the speciality of your fine descriptions. Even if we receive further informations about the locality we might not be able to decide the question, but we could exclude either Kalimantan-species or Malaysia-species.

In the last run even the young descriptions from 2005 (by Kottelat and Ng) are not certain for all times. Without clear data from genetic instigations we cannot state such slight species differentiations for all times. The taxonomic means of these taxonomists are – outdated, sorry.

[David Jones]

Yes, Peter, you are right – they could be something else altogether – another option I omitted from my recent comment. Thank your for adding that option here. Looking at the colors of the fish, especially the male in flaring/breeding coloration, they do not look to be quite “classic” tweediei, as far as I can tell, based on Lawrence Kent’s photo on the website of fully sparring males of known tweediei. And they could be from somewhere else besides Malaysia, no doubt. However, as you say, this does not prevent us from making the effort to see where the fish might possibly fit into the known taxonomic system, given it’s less that final descriptions, based on what we do known and can be observed, as in the Mimbon ’98 case. If the fish could be referred to with some kind of biological or taxonomic name, I would prefer that, and at first was not happy naming a fish after an importer and year, but now see the necessity of it, given the lack of collecting locale and other deciding factors – I am accepting, as you have pointed out, that they may have to be referred to as “P. spec. TCE 2015” ad infinitum – I reread, some days ago, your explanations I referred to of the biological naming situation, and I was reminded of the limitations there, and it enabled me to let go of my want to call them some tweedie/phoenicurus/opallios to so great an extent. Yet I admit it is one fundamental characteristic of humans to want to name and categorize the phenomena we perceive, and a necessity, so that we can talk about things with some kind of common understanding. Surely this is the whole point of the Linnean binomial naming system, adopted by the scientific community. That that system, developed in it’s own time and milieu, is now seen to be incomplete or in need of augmentation is certainly no surprise, as you have shown, given the nature of the ongoing revision, or even complete discarding, of whole scientific theories and paradigms as human understanding and consciousness shifts. From a more philosophic viewpoint – your’s and other’s perspectives and comments, this discussion and the nature of biology in general reminds us of the benefits and limitations of that naming system and our human tendency to categorize, and perhaps, invites us to see something underlying or beyond the forms we seek to name. As you and others often refer to, Beauty, for instance.

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