Taxonomy & naming
Harttia duriventris was described by Rapp Py-Daniel and Oliveira in 2011, from a type series collected at Igarapé Bacuri in the Rio Tocantins drainage (approximately 4°29'S, 49°30'W), Pará State, Brazil. The species has no synonyms.
The genus Harttia belongs to the subfamily Loricariinae — the elongate, flattened 'whiptail' loricariids of eastern South America's flowing waters. Harttia duriventris was one of several species treated in the 2011 revision of the lower-Amazon members of the genus, alongside the Tapajós-basin Harttia dissidens.
Morphology
Harttia duriventris reaches about 5 in in standard length. It shows the standard Loricariinae body plan: a depressed head and trunk, broad pectoral region, and a long, slender, tapering caudal peduncle suited to clinging in current.
Published morphological detail is largely confined to the original 2011 description, and no reliable account of sexual dimorphism has been published for this species.
Habitat
The species is recorded from the Tocantins River basin in the lower Amazon region, occurring in the upper Tocantins above the Tucuruí dam, Pará State, Brazil. It is a freshwater, demersal, tropical fish associated with the flowing-water habitat typical of rheophilic Harttia.
Specific field measurements of temperature, pH, and conductivity for this species are not published; the rapids-and-stream setting implies well-oxygenated, flowing water over hard substrate.
Feeding
No dedicated dietary study has been published for Harttia duriventris. As with other rheophilic loricariines, it is presumed to graze biofilm and associated micro-invertebrates from submerged stones — an inference from the genus and habitat rather than documented diet for this species.
Mating
No data on courtship or mating behaviour has been published for this species.
Breeding
No breeding reports or reproductive data have been published for Harttia duriventris, in the wild or in captivity.
In the aquarium
Harttia duriventris is essentially absent from the ornamental trade, and reliable husbandry data is lacking. As a rheophilic whiptail it would in principle need strong flow, high oxygenation, clean water, and a stony substrate — the demanding setup associated with fast-water loricariines. Any keeping guidance is inferential; the species is documented far more as a scientific specimen than as an aquarium fish.
Conservation
The IUCN Red List assessed Harttia duriventris as Least Concern, last assessed in 2018. The species occurs in the upper Tocantins above the Tucuruí dam; despite the presence of that impoundment, its range and population were considered adequate for a Least Concern listing. As with other narrowly distributed rheophilic loricariids, further alteration of its flowing-water habitat would warrant reassessment.