My guess is the upper fish is N. splendens and the lower fish is N. parilus. There is a LOT of variation within species in the "nudiceps group", and I'm not convinced that the characteristics used in the species descriptions by Roberts & Stewart (1976) are reliable, especially since N. teugelsi wasn't recognized until 30 years later, and the geographic boundaries of the "species" in this group have not been well defined.
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