Belongs to the Gymnotus carapo species-group, which is characterized by having a transparent patch near the posterior end of the anal fin and two (vs. one) laterosensory pores in the dorso-posterior region of the preopercle bone. Distinguished by having unique combination of characters: wider interorbital distance (44.6 - 45.9% of STO); 9 scales above lateral line at midbody; 23 - 28 ventrally oriented lateral line rami; 37 - 40 pored lateral line scales to first ventral ramus of lateral line; shorter snout (29.6 - 30.5% of STO). Differs from G. carapo or G. bahianus, two congeners also occurring in northeastern Brazil, by its color pattern in which pale interbands, anterior to vertical through first ventral lateral line ramus, are ventrally and/or dorsally fragmented, allowing union of adjacent dark bands (Ref. 93136).