It reaches up to about 12.5 cm (5 in) in standard length,[4] with females being somewhat smaller than males, is all whitish in color (non-pigmented), and essentially blind as adult, as their eyes are covered in a thick layer of skin (only retain a slight sensibility to light).

[6] L. lethops is almost only known from the mainstream of the lower Congo River in the vicinity of Bulu; however very small numbers have been found up to 20–30 km (12–19 mi) upstream or downstream from this site.

These may on occasion "catch" a deep water fish and force it up, also resulting in gas-bubble disease due to the rapid change in pressure.

[4] Consequently, when found at the surface they are usually already dead or die within minutes, although a minority may be saved by a special method where a needle is used to reduce the internal pressure.

[9][10] The closely related Lamprologus tigripictilis lives in shallow water in the exact same region as L. lethops, but it has normal pigmentation and eyes.