Gymnopis multiplicata reaches a body length of up to 500mm. The eye is covered by skin and bone, and can not be seen. The tentacle lies anterior to the eye. Teeth are monocuspid, slightly recurved, slightly arrow head shaped, and diminish in height posteriorly. Splenial teeth are present. The number of teeth increases slowly with age. The vent, is simple, transverse and lobed, and the male intromittent organ has 8-10 elongate lobes and appears fluted when everted. There are mineralized denticles embedded in the annuli of the dermal scales. There are 112-133 primary annuli and 64-117 secondaries. There are two nuchal collars, the anterior one possessing a transverse dorsal groove, and the posterior one grooved but mostly fused with the first primary annulus.
 

A Spanish-language species account can be found at the website of Instituto Nacional de Biodiversidad (INBio).