The Lacandon sea catfish[3] (Potamarius nelsoni) is a species of catfish in the family Ariidae.

[4] It was described by Barton Warren Evermann and Edmund Lee Goldsborough in 1902, originally under the genus Conorhynchos.

[2] It is known from the Usumacinta River, in Mexico.

It reaches a maximum standard length of 39 cm (15 in).

This Ariidae-related article is a stub.