This species was described in the genus Hypsolebias.

W. Costa (2006) assigned many members of the genus Simpsonichthys to the subgenus Hypsolebias (Costa 2006). Hypsolebias was subsequently elevated to a genus (Costa 2011). According to some scientists, the separation of Hypsolebias from the genus Simpsonichthys is insufficiently substantiated and, therefore, debatable.

Type locality: near rio Lajeado, rio Tocantins basin, Campestre do Maranhão, Maranhão state, altitude 133m, (northern) Brasil.

Discoverer(s): Arsênio Caldeira Baptista Jr. and João Carlos da Cruz, April 1. 2011.

Superspecies-components: 

H. adornatus, alternatus, brunoi, caeruleus, carlettoi, delucai, fasciatus, flammeus, fulminantis, gardneri, hamadryades, harmonicus, hellneri, longignatus, lopesi, magnificus, multiradiatus, ocellatus, picturatus, shibattai, splendissimus, tocantinensis, trifasciatus.

Diagnosis: separated from the closely related species flammeus, multiradiatus and brunoi by the angle of the reddish brown bars on sides of male, with a slightly diagonal angle, approximately 15 degrees from vertical (vs. fully vertical) (Nielsen et al., 2012).

Text fragment from the description.

Hypsolebias tocantinensis is described from a temporary pool located in the rio Tocantins basin, Maranhão state Brazil. Hypsolebias tocantinensis belongs the H. flammeus species-group. It is the first occurrence of genus Hypsolebias in Maranhão state. This new species differs from all other species of that group, except Hypsolebias flammeus (Costa,
1989), Hypsolebias multiradiatus (Costa &Brasil, 1994) and Hypsolebias brunoi (Costa, 2003), by male color pattern and

by the presence of a metallic blue sheen surrounding the black spots in the female. It differs from H. flammeus, H. multiradiatus and H. brunoi by the shape of the dorsal and anal fins (rounded vs. pointed) and by the orientation of the reddish brown bars in males (diagonal vs. vertical). Hypsolebias tocantinensis differs from all other Hypsolebias by the presence of, in females, irregular light brown stains on the anal fins and by the pattern of the metallic blue sheen around the black spots (completely surrounding the black spots while in congeners this blue sheen is either absent or present in vertical bars).

This species can be productive, and the fry is small. Immediately after hatching, the fry should be fed with freshly hatched Artemia nauplii (brine shrimp) or better Paramecium. As most annual species do, they spawn by diving entirely into the substrate. It is best to provide a container with a lid on top in which a hole is made to allow the fish access. That container will need to have enough peat in it for the fish to dive completely into it. For most Hypsolebias species, egg development is complete after 8-10 weeks. However, it is wise also to check a few weeks earlier to see if any eggs have fully developed. Do not let the peat dry too far because the Hypsolebias like it moist. The development will be slower at storage temperatures between 21 and 24 Celsius and speed up at 25-29 Celsius. Before watering the eggs, put some eggs in the water of about 18-20 degrees Celsius to see if the eggs hatch correctly. That usually happens within 2-6 hours. Then, if eggs hatched well and fry, swim correctly, bring all remaining peat in the water. You may need to re-pack the peat after pouring over the first group of fry to a larger tank.

With regular water changes and sufficient food, the young will grow quickly, and after about 5-6 weeks, they can already produce their first eggs. Since this genus has an annual life cycle, the expected life span in captivity is not much more than 10 to 12 months. Their life expectancy is limited to when their pool still has water in the wild. This period can vary from 6 to 8 months.

Remarks:

It is unfortunate that many species that were described never reached the fanciers. This is because newly discovered species are placed in alcohol shortly after their discovery and description. Since Brazilian regulations prohibit the keeping and distribution of these species within their own country and beyond, it is impossible to take photos of these species, and only photos from the original description can be taken.

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Max. size 38.25mm.
Dorsal rays male 20
Dorsal rays females, 13–15
Anal rays males, 26
Anal rays females 17–19
LL scale count (average) 24–25
Pre-dorsal length to % SL–53.9–60.4 %

Nielsen D.T.B. & J.C. cruz, A.C.B. Junior 2012. A new species of annual fish, Hypsolebias tocantinensis sp.n. (Cyprinodontiformes:Rivulidae) from the rio Tocantins basin, northeastern Brazil. Zootaxa 3527: 63–71. Fig. 6, Table 1.