I have 5cm L397 and L002's from Lealea. The L002's are new and I tried to get a great photo but they are still a little flighty. I got one not too bad to compare the two juvies.
Great idea in posting these pics and comparing these two species.
OK, so they come from different river systems, but they are really close, morphologically identical I'd suspect. To me I can see a clear line in the fins between the red and black in L397, but perhaps that changes with age. The lines on the head are so variable anyway, I'm not sure about using their relative thickness.
these two species will later be easy to tell apart: Panaqolus sp. "L 397" has head markings reminiscent of P. changae (heavily vermiculated), while P. sp. "L 2" shows more or less straight lines as in the first picture. Nevertheless, the fry pictures from a breeding account of P. sp. "L 397" I have here (sorry, only hard copy) show straight lines, as well. So you might have to grow them out to be sure based on this characteristic.
Regarding the light lines between black and orange, I am uncertain. No fry picture I have seen of P. sp. "L 397" shows them, they show very thick, black lines. But all of them are up to 3cm, the adults I have seen are much bigger, then. So provided this fish is somewhat 5-6cm, it is at least possible that this is a characteristic of this species.
Cheers, Sandor
"What gets us into trouble is not what we don´t know.
It´s what we know for sure that just ain´t so."
--Mark Twain