The genus name comes from Charles Frederick Hartt (1840–1878), a geologist, paleontologist and naturalist, who collected the many specimens during the Thayer Expedition to Brazil in the years 1865–1866.

[3] The greatest species diversity of Harttia, occurs in the Pre-Cambrian Brazilian Shield region.

[9] These rheophilic fishes are found in the upper courses of rivers over rocky and sandy bottoms.

[3] Sexual dimorphism includes hypertrophied odontodes on the pectoral fin spines and along the margins of the snout in mature males.

[3] Harttia exhibits considerable karyotypic diversity with chromosome numbers between 2n = 52 and 2n = 58 in the four species characterized.