- This topic has 4 replies, 3 voices, and was last updated 12 years, 9 months ago by Matthias Hofmann.
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January 11, 2012 at 1:55 pm #4068Peter FinkeParticipant
The following picture was taken by the trader himself (“Tropic-Aquaristik”, Germany) in 2008. It was sent to me with the question: To which soecies do these fish belong?
The background: The trader knew the permanent critique of specialists on the usual naming of traded Parosphromenus. We all criticized that practice of calling nearly all traded licorice gouramis “P. deissneri”. Normally, the European or American trader is rather innocent as this naming is regarded since he receives the fish from Asia, and it is the Asian exporter who names the fish in a list. And these exporters obviously like the old name “deissneri” very much and don’t read the literature that tells us that Kottelat and Ng redescribed that species in 1998. And therefore in 2008 Mr. Erbstoesser from “Tropic Aquaristik” thought to ask me whether the naming of the fish he just had received as “P. deissneri” is correct or not. And if it is not, what species it is correctly. He accompanied his wish with two pictures just taken form his freshly filled tank, this is one of the two.
That the fish was not deissneri was clearly to be seen at one glance. (The true deissneri is very easily to be recognized). But what ws it? Clearly one of the many undescribed forms that emerged in the trade in recent years, often with Sumatra as source. Obviously, there were still good Parosphromenus-habitats on Sumatra that were tempting for exporters and their catchers because they could caught many fish with small effort in short time each year some months after the spawning season. I had a suspicion but I was unsure and therefore forwarded the picture to my friend Martin Hallmann, as specialist on the bintan-group. And Martin confirmed my suspicion: It’s the form spec. Sentang (or even sometimes falsely called “sintangensis”) from the Sumatranian Sentang-area, a form since then dominating the international trade of Parosphromenus including different names; often they are called “deissneri” and often “bintan”. The former is definitely false, the latter may even be correct, but we don’t no so far, since we have no genetic data up to the present day that confirm that identity.
But this is only the background to the picture I want to show you. The interesting thing is: It shows only males! A tank full of a special Parosphromenus forms but males only! I do not know why that is the case. We know of the fact that pH, temperature and other environmental factors decide about the sex of fish-indivuduals (other than with mammals or birds), but it is highly improbable that this happens in the natural habitat. Maybe that some chemical (?) input has changed the water conditions, or have the animals cought been selected fot males and females afterwards? But why? Many questions. At any rate I thought to show that picture to all.
January 12, 2012 at 3:16 am #4072helene schoubyeKeymasterI quess its probably not the case with this excample, but I know that in some other species – like red cherry shrimps (not a fish:)) – but there you always used to have a problem with finding males, – and some people said it was because the males were much less attractive than the females, so in the shop they wouldnt be able to sell for the same amount of money, – so they were simply taken out before coming to the shop.
I also heard the same thing about a fish species, which unfortunately I cant remember which one was – but where it was a known problem, that what appeared in shops was alway only one sex (the most attractive one) – because for ordinary aquarium keeper perhaps looks is more important than breeding.
But I must say, I doubt in this case that someone (like at the location of capture) would actively take away the less colourful and attactive fish (in this case the females) and keep them away from appearing in the shop .. but who can say ?January 12, 2012 at 9:07 pm #4073Peter FinkeParticipantI know of these rumours too. They were told for several times when an exciting species was new and expensive. Probably – the rumour said – the exporter or the breeder sells only one sex in order to prevent others to spoil his good business. This was told for instance with Dario-species and with Botia-species, but there was never a proof. I think it was nonsense, camouflaging the fact that one was unable at first to breed that new species. Certainly no export company takes measures to single out the sexes with Parosphromenus; they can be pretty sure that most licorice gouramis will be dead in the tanks of unexperienced aquarists in a few months time. This is quite in time before the new spawning and catching season begins, and they can sell all fish again.
One of the motives of the Parosphromenus-project is to change this mentality of mere “keeping” that fish. The most interesting thing with licorice is their behaviour and the most interesting behaviour is shown during courtship and breeding. We must learn to breed them, not only to keep them.
But I admit: for that purpose you need both sexes. The people who buyed that spec. Sentang-fish out of that tank I showed had no opportunity to breed them. They received only males. And why? I don’t know, but I suppose that the catch was like this. And why? I don’t know, but I suppose some kind of environmental change (perhaps by a chemical input, or merely a rise in temperatures following the cutting of high trees around), and the developing fry and growing young developed (nearly) into males only.
Or what other cause could reasonably be thought of?January 12, 2012 at 9:22 pm #4074helene schoubyeKeymasterAt some point I had these fish – shown in the picture – they were id’ed as p.sintang / sintangensis ? –
I remember I had to buy many fish because most of them were males as well.They were actually then one of the species which did not prove so difficult to breed, – but here again most were males.
I kept them as in my other tanks, at that time though I was not very good at keeping the ph low, so it was around 7-7.5March 15, 2012 at 11:52 pm #4297Matthias HofmannParticipantMal in loser Folge ein paar Fotos von der Anlage und den Tieren.
Fotografisch muss ich mich noch verbessern; aber daran arbeite ich…. -
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