More pictures of the habitat.
I noticed in a stream filled with T-barbs, Systomus binotatus, Aplocheilus panchax, half-beaks, harlequins, Apogon barbs and Rasbora elegans a distinctive few specimens of a rasbora that has the build of R. elegans, but a clearly red tail. They also lack a prominent spot on the flank, while a spot is evident on the base of the tail.
The pictures show the red-tailed fish as well as R. elegans proper for comparison. I am inclined to see this fish as not just a biogeographical variant of R. elegans, given that its sympatry with R. elegans proper (which should by right subsume any insignificant phenotypical variations back into the mother population). So it's possible that some form of sexual exclusion may have taken place to allow the emergence of this fish. The red-tailed rasbora also seem to spar only with each other, and not the regular elegans.
Does anyone have any ideas?
More pictures of the habitat.
It's wonderful to be able to see so many fish in local (local, right?) streams...
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I'm crypt collecting... Starting cheap, now have Cryptocoryne beckettii, C.beckettii var petchii, C.crispatula var.balansae, C.griffithii(Melted! ), C.nurii, C.parva, C.pygmaea(Melted! ), C.tonkinensis(Melted! ), C.walkeri, C.wendtii 'Brown', C.wendtii 'Green', C.wendtii 'Green Gecko', C.wendtii 'Tropica' and Cryptocoryne x willisii
Oh, juggling is hard work, man!...
wonderful pics, would like to have seen the rasboras profile shot to see for myself, any possible wayto do that, the harlequin looks beautiful was there a shoal or just the odd one.
cheers mick
Harlequins seem to prefer somewhat faster flowing and deeper sections of open water along the stream. They don't form tight schools, just loose aggregations of individuals (although juveniles will form larger groups and prefer more sheltered, heavily planted nooks).
thanks for the info budak, we only see them in tanks, they have the same
shoaling as some of our fish over here like the roach and rudd,
btw they are some of our cyprinids in GB.
cheers mick
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