how can you tell if they are hybrids. what are they a hybrid between.
The only
practical means of identifying hybrids is to compare fishes to photographs of known species, having particular regard to colouration and patterns thereof. Naturally such processes are fraught with hazard, particularly since in the case of G multisquamatus as there is some confusion over this species. It is however worth noting that the rainbowfish preservation group has doubts about the presence of genetically pure multis in Oz. This is not to say hat they don't exist, but people in the know say that they have not seen any for some time. Furthermore it is unlikely that if they are present, that they will be commercially available.
G multisqamatus will hybridise with other Glossolepis species, and probably with Chilatherina species, though it is probable that crosses with the latter are sterile.
It is unlikely that any new bloodstock of multis has reached Australia in the past 20 years, so the worry is that any being sold are unlikely to be pure bloodstock; or that they have changed radically as the result of inbreeding (this later scenario is known in several Melanotaenia species).
Syd.