I caught that species in Peru two years ago (HERE, HERE, and HERE) and tried to import them back to the USA, but they died before being shipped. My uncertainty of species ID is that I recall the L. griseus I caught as having pale pigmentation on the fins, similar to what is seen on the photos on the CLOG page, but the fish at FWE have a black margin to the dorsal fin and caudal fin, and a black spot at the base of the caudal fin, as can be seen in this photo here (Direct link):
So I jumped at the chance to get a group L. griseus and ordered all five pieces (that was all FWE received), hoping to get both sexes. The shipping box wasn't full, so I added three female to go with my 6-year old colony of the same, but it was very male heavy (maybe 1 female at most now, and I'm not even sure about that).
When the fish arrived, it turned out the five whiptails were actually three Limatulichthys and two (one of my "bucket-list" fish)!
I'm super excited to have gotten these, although I worry that I don't have both sexes of either species because of the numbers. (I have only a 50% chance with the R. melini, and a 75% chance with the Limatulichthys).
Let's hope and pray for the best. The fish are big (biggest being about 9cm SL), but they are not mature. So hopefully as they grow and feed, I find both sexes.
Cheers, Eric
Nice fishes!