Scale bar = 20 mm Babelichthys is an extinct genus of crestfish from the ?Late Eocene-aged[1] Pabdeh Formation of Western Iran.

[2][3] The single known specimen consists of a head and the front-most region of the dorsal fin, preserving the extremely elongated and enlarged first dorsal-fin ray.

It has been inferred that Babelichthys had a highly elongated "crest" at the front of its dorsal fin that projected horizontally forwards like a horn, akin to that of the extant unicorn crestfish (Eumecichthys fiski) but even larger and more elongated.

[2] However, some studies find Lophotidae to be paraphyletic, and place Babelichthys as an indeterminate taeniosome.

[4] The genus name Babelichthys literally translates to “Babel fish” in Greek, named after the teleost-like, ear-dwelling, polyglot extraterrestrial species from The Hitchhiker’s Guide to the Galaxy, as a reference to the very peculiar, almost alien-like, appearance of the genus.