It’s P. spec. Sentang from Sumatra. This has been the worldwide most traded form in the past years. Often it is called P. spec. bintan, for it is certainly closely related (if not identical) with P. bintan.
Therefore we can say: The Parosphromenus in aquaria that are most widely distributed do not clearly belong to one of the eighteen species scientifically hintherto described, but to two of the hitherto undescribed forms, namely “spec. “blue line” and spec. Sentang. It’s ridiculuous, isn’t it? But it’s the truth, because the great majority of licorice gouramis in the aquarium are not self-caught fish or fish stemming as offspring from such fish with a definitely know place where they were caught, but from trade. And the forms that are traded mostly are the both I mentioned.
(I removed the picture formerly at this place because it is not necessary for answering the question of Hendrik’s. But it is interesting in itself for all: Therefore I show it at a better place: in the picture’s section).