Was originally described as Melanorivulus ubirajarai which is not followed in this site.

Rivulus ubirajarai, and Rivulus kunzei, are described from the upper Araguaia river basin, central Brazil; both are considered as closely related to other species endemic from the same area. Rivulus ubirajarai shares with R. litteratus a unique colour pattern of caudal fin in females (short grey stripe between caudal spot and bar on the middle of the fin). Rivulus kunzei shares with R. kayapo a unique colour pattern of flank in males (irregular horizontal rows of red dots forming reticulate pattern). Rivulus ubirajarai is mainly distinguished from R. litteratus by having a distinct colour pattern of flank and dorsal fin in males, consisting of not overlapping chevron-like red oblique bars on the flank and rows of light grey spots on the dorsal fin in males, dorsal fin at vertical through the base of the 9th anal-fin ray, and 33-35 scales on the longitudinal series. Rivulus kunzei mainly differs from R. kayapo by having 29-30 caudal-fin rays and the presence of dark grey dots on the sub-distal portion of the dorsal fin and middle of caudal fin in males. The discovery of the two new species supports the recent report of a unique high species diversity of Rivulus in the area drained by rivers originating in the Caiapós hill. The combination of high species diversity with quick habitat loss makes rivulid species endemic to the Caiapós hill area highly threatened with extinction, deserving special concern.

No records are available for the breeding of this species but this will not differ very much with the way other small Rivulus breed.

Remarks :

First of all, life animals are needed for further study of this new species.

Max. size 29.9 mm SL.
Dorsal 9 - 10,
Anal 14 - 16,
D/A +9,
LL scale count 33 - 35