Taxonomy & naming
Harttia trombetensis was described by Rapp Py-Daniel and Oliveira in 2001, in Ichthyological Exploration of Freshwaters (volume 12, number 1, pages 79–96), in a paper introducing seven new Harttia from the Amazonian–Guyana region. The type locality lies in the Trombetas River basin, above the Cachoeira Porteira falls, in Brazil. The Catalog of Fishes (Eschmeyer, CAS) recognises Harttia trombetensis as valid (spid 66300).
The genus Harttia is part of the subfamily Loricariinae, the slender 'whiptail' branch of the armoured catfishes (Loricariidae). The specific epithet trombetensis refers to the rio Trombetas, the river system to which the species is endemic.
Morphology
Harttia trombetensis reaches up to 7 in in standard length (FishBase Ref. 36389). The body is elongate with a flattened cross-section, in keeping with the whiptail loricariine body plan.
The original description diagnoses the species by a combination of internal and external characters: an abdominal covering with two unplated areas separated by a thin transverse chain of platelets in adults; a short pectoral spine (contained 3.5–5 times in standard length); a caudal peduncle whose length together with the postanal length is contained 2–2.6 times in standard length; a tubular stomach; a long intestine (roughly 14 times the standard length); and 29–30 keeled lateral plates along the body.
No data on sexual dimorphism in this species has been published.
Habitat
The species is restricted to the Trombetas River basin above the Cachoeira Porteira falls in Brazil, a section of the Guiana Shield drainage isolated upstream of that cataract. FishBase characterises H. trombetensis as a freshwater, demersal fish of tropical waters, consistent with a bottom-associated life in flowing upland river habitat.
Detailed measurements of the water chemistry, depth, and microhabitat at the type locality have not been published here, but the long intestine reported in the original description is typical of fishes processing large volumes of low-nutrient plant and detrital material in such environments.
Feeding
No dedicated dietary study of Harttia trombetensis has been published. The species has a tubular stomach and a notably long intestine (about 14 times its standard length), a digestive configuration associated with herbivory and detritivory in loricariids. This anatomy, together with the general feeding ecology of Loricariinae as biofilm and algae grazers, suggests a largely herbivorous to detritivorous diet, though this has not been confirmed by direct gut-content analysis.
Mating
No information on the courtship or mating behaviour of Harttia trombetensis has been published.
Breeding
No breeding data for Harttia trombetensis has been published. Its reproductive mode, clutch size, and parental care are undescribed, and there are no records of the species being bred in captivity.
In the aquarium
Harttia trombetensis is not established in the aquarium hobby, and no husbandry experience with it has been published. It is known from scientific collections in a remote, falls-isolated stretch of the upper Trombetas. Any care recommendations would be speculative.
Conservation
The IUCN Red List assessed Harttia trombetensis as Least Concern, with the assessment dated 7 November 2018. Although the species has a restricted distribution above the Cachoeira Porteira falls in the Trombetas basin, the assessment did not identify it as facing a level of threat warranting a higher category at the time of evaluation.
Upland Guiana Shield rivers can be affected by mining and associated sedimentation and water-quality changes, which is a general concern for endemic fishes of these systems; however, on current evidence the species is not considered threatened.