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I should remind you of the fact that the decision on the sex is in some aninmals (including fish) not determined by the genetics in the moment of fertilization, but much later by environmental factors. I wrote about this several times already, including this website. In Germany, the biologist Steinberg has investigated and published on this issue especially in the case of fish. This is an issue of high importance to the fish industry for in many cases of species it is of great importance for breeders of fish we need as our food to produce more females (eggs!)than males (milk!). There is no doubt in general; the difficulty lies in finding out which factor is responsible in an individual case situation.
The most important factors that have been found to be relevant for this in fish are the pH, the share of humic substances, the temperature and the general composition of minerals. This explains spawns with dominating or pure males resp. females. Every group of fish has its own optimal balance of these factors. Differences among the Parosphromenus species exist, too, but they are slight only.
As a matter of practical help every breeder is advised not to start a specific breeding with extreme values that are conveniant for him or her (e.g. lowest or highest possible pH resp. temperature, no humic substances or abundance of them, or an unusual composition of the mineral contents, for instance by using a water with too high a share of Ca) but to prepare the set up well informed about the ecological situation at the original locations. Generally speaking, too many spawns are performed in water with too high a mineral share, too high a pH, too low a share of humic substances and to high a temperature. Mind, that the pH of the tropic waters in blackwater regions are never without a high share of humic substances, are often of lower temperature in the rainy seasons of mating and rearing the young, when the mineral content of the water is most similar to pure H2O.
Hello Peter, that’s a problem in our already rather numerous threads: “I wrote this several times already….”….. Sometimes I remember, that someone had written already very good information about a subject, but can’t find it again … So I will now begin to paste and copy your post in my documents about “Paros” …. So I did already also with Pawels blackwater recipe …
If you read the actual threads, you think, “that’s very precisely worked out, I will remember it” ….. But some weeks later ……I’m thinking like Peter. Without humic it is certainly, but just not necessarily good. I for one think that I could not breed as many Paros without humic substances. I also tried it on several occasions with no peat, with some, such linkei works quite well, but most other species need at least one Torfzusatz. That depends, I think, along with the germ load, no humic = many germs, and these prevent the egg fertilization, humic substances prevent high bioburden. Germs clog the capillaries of the egg so that the sperm no change has ever to penetrate into the egg before. So I have learned again on a VDA seminar 🙂
Hi everybody,
@Helene: yes, they have 3 caves aus well aus some leaves in the “linke-Style” that Should Provider enough space and opportunities for breeding.
@Peter: I know of these problems and i think wie just have to experiment a little and maybe my stock will produce more females than males… We will See…I have the same conditions for all my fish (except parvulus, which I keep in a bit lower ph)
but otherwise no big difference concerning humic substances, softness etc.
I had the same problem once with harveyi, and at that time started a thread on the subject.
You can read that here https://parosphromenus-project.org/en/forum/4-Breeding/1364-p-harveyi-males-only.htmlWith these p.tweediei, there are females, but majority males. This was an unsual big hatch for me, around 40 fry. The harveyi batches was also big.
Most of the times when I breed extensive there seems to be a more normal and even distribution of male females.Helene, thanks for the link to the thread you started on this question, I believe I missed that one in reading so many threads before getting my first paros. So, you and Peter and others have considered this question at length and even made some interesting observations. Hopefully you have found or will find a solution by trying different things. I know, when I said “maybe you could experiment”. I then thought about how much work that really takes, and time. So just take my comment lightly 🙂 Lawrence Kent sent me 7 tweediei young (9 weeks old) and already I can see at least two pairs in the mix under magnification. He thought they were not sexable, so maybe he just picked out 7 random fish (he has quite a lot of them) and if so, maybe this suggests a more balanced ratio in his offspring. I will ask him what water parameters he keeps and breeds his in.
There are now – again – some more new information regarding this particular species.
I was contacted by Martin Hallmann, who told me that he believes this particular species is very much like the fish he once had, – which was P.cf. alfredi ‘Kota Tinggi’. Martin also send me some photos of the fish he had some years ago, – and I have to say the resemblance is very striking.
Martin wrote some thoughts regarding why he consider this identification to be more right than p.tweediei, – and he also gave me permission to explain this in forum (together with the photos) he send, – but I simply have to admit, that my understanding of the german is not good enough – as well as my understanding of the different problems around identification of species, so I am afraid of saying too much about this, – I might get it wrong. I have uploaded two of Martins photos in the ‘other forms menu’ under sp.alfredi Kota Tinggi.
I know from Peter, that there still could be some questions which could be asked regarding whether this is p.tweediei or p. alfredi and its perhaps not just the question of which is more right or not, – but perhaps also a question of how one looks at the whole question of identification.For me its just good to hear the different opinions, I can certainly see, that it makes sense to see this fish as P.cf.alfredi.
The next problem in this is to really decide what to do, – and how to go on about it in Census. At the moment I report the fish by the name it had from the shop, and keep it as such in order not to loose ‘track’ of it. But I also spoke to Peter about that it cannot be right to continue to report a species by an obvious ‘wrong’ identification.We’ll see. I will let you know what the next development is. For me, its mainly a proces of learning through all this, – the fish is still beautiful no matter what it is, – and it doesnt change anything much whether its one or the other, – but I have learned a lot through this fish about the difficulties around the species tweediei, rubrimontis, alfredi 🙂 …
Yes, Helene is fully right in decribing these difficulties. When I wrote the Parobuch “Prachtguramis” together with Martin Hallmann, we quarreled a lot about the question which fish Dr. Walter Foersch had got by Dietrich Schaller, who caught them for him after having visited Dr. Alfred, at that time (1975) head of the Raffles museum in Singapore. I had myself seen these fish in Dr. Foersch’s fishroom, indeed I had got some pairs of his offspring from him for myself, my first Paros. We all called them “deissneri” at that time, but nearly forty years later writing that book it was entirely clear: they had certainly not been deissneri but something between rubrimontis, alfredi and tweedie. I voted for tweediei although the fish showed more blue than the purely red we knew at that time from the typical tweediei. Martin voted for a mix between rubrimontis and alfredi, and in the end we decided for that spec. Kota Tinggi. It was Allan Brown who had given us fish that he had caught in the Kota Tinggi-region, and indeed, they resembled most the pictures left showing the offspring of Foersch’s fish.
But what does that mean for the question alfredi-tweedei-rubrimontis? I tell you what: Dr. Kottelat, who did the scientific descriptions of these three species only lately, in 2005, decided from dead museum specimens to distinguish these three species. It’s the same problem we know from ornithology: The old science of the birds was a pure museum-science. People shot the birds and then science began: measuring, weighting, describing the bodies and so on. We can thank god that this has ended by the protest of many laymen in the late 19. century! But in our fish, we still have that museum-taxonomy. That is the problem. As long as an outdated method of describing new small fish defines the species, we are often incapable of to determine rightly our living fish that has not been assigned with undoubtedly true a location.
The question remains open whether the fish we call spec. Kota Tinggi and which has come the uncertain ways of the trade is a fish more akin to alfredi or more akin to something else. If the location would be clear this would point to the nearness of alfredi, and that strengthens the position of Martin’s. But we do not know anything about locations in this case and the original locations are anyhow destroyed nowadays; we can be happy if we still find Paros somewhere near to them. The catchers of these fish here in question must have used such unknown new locations. But the real problem is that the hitherto scientific knowledge forces us to decide between those three species, what in truth is probably an intermediate form not decribed scientifically.
My conclusion is threefold: 1. We have nice fish and are happy that they still can be found, although nearly all great traditional locations around are destroyed for ever; 2. In this case the determination spec. Kota Tinggi is the most likely one, but to call this cf. alfredi is an open question; and 3. We need new methods of taxonomy, definitely including genetic methods. From all we know from this research up to now, the genetic differences between alfredi, rubrimontis and tweedie are so small that a genetic researcher would not have splitted these three into fully developed species. They may represent developing species, but nowadays the economic destruction of the Malayan countryside puts for ever an end to this development.
[quote=”helene” post=5171]
Martin wrote some thoughts regarding why he consider this identification to be more right than p.tweediei, – and he also gave me permission to explain this in forum (together with the photos) he send, – but I simply have to admit, that my understanding of the german is not good enough – as well as my understanding of the different problems around identification of species, so I am afraid of saying too much about this, – I might get it wrong.
[/quote]Helene, I think it is interesting for the community what Martin Hallmann thinks of your fish – so if I can help by translating Martin’s statement, just let me know.
[quote=”Peter Finke” post=5172]Dr. Kottelat, who did the scientific descriptions of these three species only lately, in 2005, decided from dead museum specimens to distinguish these three species. It’s the same problem we know from ornithology: The old science of the birds was a pure museum-science. People shot the birds and then science began: measuring, weighting, describing the bodies and so on. We can thank god that this has ended by the protest of many laymen in the late 19. century! But in our fish, we still have that museum-taxonomy. That is the problem. As long as an outdated method of describing new small fish defines the species, we are often incapable of to determine rightly our living fish that has not been assigned with undoubtedly true a location.[/quote]
Hello, Peter,
I understand what you mean by condemning the “outdated method of museum science”. But I think you wrong this method by completely rejecting it. And fortunately it is not true that the “old museum science” including measuring, weighing, describing has ended (but luckily most of the killing on purpose has!).The museum science still has it’s value – in no other way you will be able to make precise measurements, to count feathers (or scales), to compare a great lot of individuals. This would not be possible using living animals – not to speak of the fact that in museum collections you have access to species from regions which might be out of reach today (e.g., due to political facts, due to destruction). You have access to species which already suffered extinction in nature. But I agree with you when you say it must not be the only method to describe species.
The correct and comprehensive description of a taxon is like putting together pieces of a mosaic – every piece is important – museum taxonomy and morphology as well as behavioural studies in nature and captivity, genetics, molecular investigations, DNA-barcoding and so on. Not one of these methods is the ultimative and only one – and none is completely to be abandoned.
An excerpt I love very much, from a wonderful book of John Steinbeck (and Ed Ricketts) – “The log from the sea of Cortez”. To show that I understand that museum taxonomy can not be all ………… but I have to strike a blow for it if you condemn it like you do ……….
[i]”The Mexican sierra [a kind of fish] has ‘XVII-15-IX’ spines in the dorsal fin. These can easily be counted. But if the sierra strikes hard on the line so that our hands are burned, if the fish sounds and nearly escapes and finally comes in over the rail, his colour pulsing and his tail beating the air, a whole new relational external reality has come into being.
The alternative would be to sit in a laboratory, open an evil-smelling jar, remove a stiff colourless fish from formalin solution, count the spines, and write the truth ‘D. XVII-15-IX.’ There you have recorded a reality which cannot be assailed – probably the least important reality concerning either the fish or yourself.”[/i]
You are wrong in thinking that I “condemn” the museum taxonomy. I condemn it to be the only method, sufficient for describing new soecies of Paros scientifically. That means quite some restrictions: They could perhaps be suffient today for some organisms, even fish, that had not been detected and described before. Even birds. But in most cases that are relevant today it is entirely insufficent. And this is the case with Paros who only can be distinguished by slight differences in structure and colouring. Yes, even slight structural differences may occur and not indicate a species difference. May, not more.
You condemn, namely my way of speaking, I do not. The way I spoke was short for “entirely insufficient for describing new species of Paros in cases where only slight differences in structure and colouring are to be seen at the phenotypes”. Let alone the dead phenotypes.
All we know hitherto is that Parosphromenus is a highly variable genus still in heavy development at the present day. The new taxonomics that is used in birds for instance knows semispecies for instance, but uses has genetic informations in the background. Even the old concept of a subspecies is not used in Kottelat’s world, too. But he can’t, I admit, not using living fish, their behaviour, genetics. And that is not enough, I am sorry.
Peter, I am sorry, but I can’t help having the impression that you didn’t read my post thoroughly and completely. Don’t be cross with me: Your answer seems to be the spontaneous reaction of someone who is annoyed of being criticised.
If you read my post again you will find at last that we share a similar opinion: One method (e.g., museum taxonomy) is not enough for thoroughly describing a new species.
This is something I already agreed with you in my last post.But how but “condemnation” would you call this phrasing:
The old science of the birds was a pure museum-science. People shot the birds and then science began: measuring, weighting, describing the bodies and so on. We can thank god that this has ended by the protest of many laymen in the late 19. century! But in our fish, we still have that museum-taxonomy. That is the problem.
I could not let this form of words pass unchallenged. There’s nothing that let’s us recognize that you still believe this method to be a valuable one – among many others. It simply sounds like a clear and total refusal. It definitely doesn’t sound like:
“entirely insufficient for describing new species of Paros in cases where only slight differences in structure and colouring are to be seen at the phenotypes”
I did not mean to offend you – but I think it should be permitted to contradict you if one has another opinion (or knowledge!).
(By the way – killing and collecting animals for museum collections was definitely not ended by layman protests by end of the 19th century. There have been many expeditions which collected lots of animals for scientific purposes up to the 60s and 70s of the 20th century …)
Stefanie, I am sorry but you are wrong. I criticize the state of the Paro-taxonomy, nothing else. And what I say about ornithology is a fact of the history of science. Read Dominik Mahr, Fortschritt oder Rückfall? in: P. Finke (Hg.), Freie Bürger, freie Forschung. Die Die Wissenschaft verlässt den Elfenbeinturm. München: oekom 12105, 119-123. There we have another context, but this does not make my critique invalid. Many museum have big and valuable collections of bird skins, many of them were added recently, and I do not criticize that. But the modern science of birds would not have developed as it has if the methods of dealing with dead birds would have remained the same up to now. I don’t criticize that dead fish or birds are collected in the museums. But I criticize that our hitherto descriptions of the Paro-species are not on the level that is comparable to other taxa. Even the museum ornithology has advanced since long from describing corpses to another, advanced level. If we took behaviour (not to speak about the genes) as containing valuable additional information, ornaticauda and parvulus would probably not retain that status they have today. Not to speak about sumatranus.
I see that you say similar things, of course. But there is a remarkable progress made by many taxa that has – at least for our Paros – not been made up to now by including all the other important information not to be seen at the phenotype level. I do not state that I could it do better. But I state as a researcher on science in general the revision of the Paro-taxonomy including all that other informations is necessary. Fortunately there are people working on that.Hey everyone,
it has been a while since someone has added something here so I wanted to get this topic out again.
In the Hamburg-Meeting, I got some of the “P.tweediei” offspring from Helene. After a few starting problems they started to breed and have gotten in a really good state here so I have quite many of them. However, I never managed to capture good pictures to maybe help the determination of the exact name they should have.Unfortunately and due to a mistake of mine, I lost many of the animals from the F2 Generation and all the older fishes this weekend. Now there are perhaps 6-8 left (there used to be around 20) and, luckily some females too. (It was a problem that more male fishes were born than females).
Now as I observed them much more since this big loss, I was finally able to get some good pictures of two males displaying so i would like to share them with you here…
So what do you think.. tweediei???
No tweediei but very nice. I know the pictures of the males one generation before from Helene too. We had very near forms in IGL about 10 years before and one of them we called P. cf. alfredi Kota Tinggi. It could be a alfredi-near-form with black ventral filaments, but we didn`t know the real origin.
Cause they are no tweediei, please call them P. cf. tweediei (only because someomne has started like that) “trade…..20..” Helene should help, she should know from wich dealer they came.
The worst would be, that they get mixed with P. tweediei (from Pontian, Pekan Nenas).Best wishes, Martin
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