Many thanks, Peter, for your message, and helping to ID these fishes. And surprise that they may be something other than P. sumatranus – they would be interesting enough were they simply sumatranus! I must say that, although the photos fail to capture it, there does appear to be some kind of dark spot or marking on the rear portion of the dorsal fin, but it is fairly indistinct and not as pronounced as some of the classic photos of P. sumatranus show. If I can get a better photo of the male showing that marking, I will post it – it may or may not help with the ID.
Also, I will try to find out more information about the origin of these paros, but they do come from the commercial trade, so not certain if sure information can be given. Either way I’ll give an update here.
Regards,
David