Maratecoara is a genus of small killifish in family Rivulidae, restricted in the atlas to Brazil. The 4 species are tiny, 1–2 in, and belong to the same South American seasonal-killifish lineage as many Cerrado and coastal-plain rivulids, groups adapted to living in shallow pools and marshes that can dry out between rainy seasons.
None of the 4 species - M. formosa, M. gesmonei, M. lacortei, and M. splendida - carries an established common name in the atlas, reflecting a genus known mainly to killifish specialists and regional ichthyologists rather than the general aquarium trade. The conservation picture is more concerning than for most small characin or livebearer genera in the atlas: of the 4 species, 2 are assessed Vulnerable, 1 is Least Concern, and 1 is Not Evaluated, consistent with the pattern seen across many range-restricted Brazilian seasonal-pool killifish, where a single stretch of habitat converted to agriculture or drained for development can threaten an entire population.