Name by description Anablepsoides vieirai. Alternative name Rivulus (Oditichthys) vieirai.

New species from the Rio Itapecuru basin, Eastern Amazon, Brazil. Belongs to the R. urophthalmus species group, here following Killi Data International remained in Rivulus.

Rivulus vieirai, is a new species, from the rio Itapecuru basin, eastern Amazonia, Brazil. It is described in the same paper with R. luitalimae belonging to the Rivulus limoncochae species group while Rivulus vieirai belongs to the Rivulus urophthalmus species group. Rivulus luitalimae is distinguished from other species of the Rivulus limoncochae species group by having blue pelvic fins and one longitudinal line with 6 minute contact organs on the sides of the body. Rivulus vieirai is distinguished from other species of the Rivulus urophthalmus species group by the presence of black spots in the head, opercular region and behind the eye and a higher number of scales in longitudinal series.

Distinguished from all other species of the Anablepsoides limoncochae species group by several unique color pattern features: pelvic-fin light blue (vs. orange, yellow or light yellow), caudal-fin reticulated, light blue and light yellow at basis and distal area hyaline, with its upper portion light yellow (vs. orange), anal fin with reticulated basis, light blue with red brown dots at its basis, distal portion pale yellow (vs. reticulated basis, red dots with distal portion golden yellow with a black bar in A. elongatus and A. christinae, anal-fin with bright blue-green basis with rosy spots between the rays, followed by a line of red dots also between the rays and distal portion bright orange without black border in A. hoetmeri, blue basis with distal portion light yellow with black bar in A. rubrolineatus, anal fin pale yellowish, its basis whitish with red spots on posterior portion in A. parlletei, anal fin pale grey, with cream yellow basis and red spots in A. lineasoppilatae), dorsal fin origin posterior to the last anal-fin ray (vs. at the level of the 13th ray in A. hoetmeri, A. rubrolineatus and A. elongatus), one longitudinal line with 6 minute contact organs, beginning at the level of the trunk reached by tip of the pectoral fin and ending at the level of the anal fin (vs. present at pectoral fin or 1-3 contact organs on antero-ventral portions of flank or on each scale of midventral portion of flank or two longitudinal rows of 18-20 contact organs in A. hoetmeri), dorsal origin neural spines (26 vs. 21-23 in A. urubuiensis or 16-17 in A. hoetmeri), vomer teeth number (4-6 vs. 1 in A. urubuiensis and A. hoetmeri or 2-3 in A. parlettei and A. lineasoppilatae). 

Keeping and breeding is easy but a tight fitting cover on the aquarium is necessary because their ability to jump, even through the smallest opening, is unbelievable.

This species can, if there is enough space for them, be housed in a tank with more than one male and several females. If separated before and brought together again however, they can be very aggressive towards each other and fight to become the dominant fish. The best way to produce numbers of fry is to put a pair or a trio in a small tank of about 10 litres with a small filter in it or with some aeration. On the bottom of the tank place some peat moss or dark gravel and a floating "mop" to give space for laying their eggs. The fish will, if they are fed a rich variety of live food, spawn during their whole adult life and produce daily between 5 to 15 eggs.

The eggs should be collected by hand and stored for about 14 days in a small container. Eggs are 1.6 mm and amber coloured. It is wise to add an anti fungus to the water you store the eggs in, to prevent fungal attacks.

After hatching the young fry can eat fresh artemia nauplii without any problem. It takes 4 to 5 months to raise them to maturity. Often the males far out number females. For some species this can become a major problem for the breeder, as he has to raise many fry to enable distribution of a few pairs to other hobbyists. Recent personal tests found that lower pH levels during the time of hatching gave a higher percentage of females. To achieve this I used some peat moss that I added to the container with the eggs just before they were ready to hatch. This peat moss also is a good way to prevent eggs from being attacked by fungus.

Their lifespan can be up to 3 years in captivity.

Remarks :

Max. size 36 mm.
Dorsal 8,
Anal 11-13,
D/A 11,
LL scale count (average) 43-44
Pre- dorsal length to % SL – 74.4 %
Depth to % SL – 20.1 %