Christian, are these (at least the males?) a deep red,
almost cherry red fish? TFH magazine (February 2005)
ran an article by Heiko Bleher on his 1999 collection
of parva. I was surprised by the intensity of the
mature males' red, which contrasted in a very striking
manner with a dark stretch on the sides behind their
gills.
Didn't remember such colors in Allen's book. When that
photo was again looked at (on page 136), it seems to
be on a table. One can guess it would been removed
from a preservative, placed on a lab table and
photographed. Dr. Allen noted that it had not been
kept in captivity as of the publication of his book,
though he originally collected it in 1989, from a very
obscure spot, and described it in 1990.
Allen's discussion of it's colors suggested variable
fish. "Males are either a bluish to mauve with a black
mid-lateral stripe or silvery with red speckling and
narrow red stripes between each scale row on the side
of the body."
Bleher's article also includes the image of a
semi-adult with very unexceptional colors. Could the
fish pictured in the 2002 All Rainbows and related
families likewise be youngster?
Probably wouldn't be the first time aquarists were
surprised by males who finally matured and colored up.
:)
Thanks and all the best!
Scott