Taxonomy & naming
Harttia absaberi was described by Oyakawa, Fichberg and Langeani in 2013 in the journal Neotropical Ichthyology (volume 11, number 4, pages 779–786). The Catalog of Fishes (Eschmeyer, CAS) recognises it as a valid species of the genus Harttia (species id 73087).
The genus Harttia belongs to the subfamily Loricariinae, the slender, depressed-bodied 'whiptail' loricariids characterised by a long, attenuated caudal peduncle and the absence of an adipose fin. The genus is widespread across eastern and central South America, with a notable concentration of species in the coastal and upland drainages of southeastern Brazil and in the Amazonian–Guiana region.
The specific epithet honours Aziz Nacib Ab'Saber (1924–2012), the influential Brazilian geographer and geomorphologist, in recognition of his contributions to the understanding of Brazilian landscapes.
Morphology
Harttia absaberi reaches approximately 3 in standard length in the largest examined specimens. The body is elongate and dorsoventrally depressed in the typical Loricariinae fashion, tapering to a long caudal peduncle. The dorsal fin carries a single spine and seven soft rays; the anal fin a single spine and five soft rays.
Beyond these meristic counts, detailed published colour and pattern data for this species are limited in the sources available here. As with other small Harttia, the body is armoured with overlapping bony plates, the mouth is ventral and disc-like for adhesion to the substrate, and the overall form is adapted to life pressed against sand and rock in flowing water. No reliable information on sexual size differences in this species has been published in the sources reviewed.
Habitat
Harttia absaberi is endemic to the upper rio Paraná drainage in Brazil. The type locality is the ribeirão São Mateus, a small clear-water creek roughly 3–7 ft wide and about 2 ft deep with a sand bottom. The species has also been recorded from the rio Passa Cinco, a larger river some 16–33 ft wide and 3–7 ft deep, with fast-flowing clear water over sand and rocky stretches.
This pairing of small headwater creeks and larger rocky-sand rivers indicates a fish at home in clear, well-oxygenated, flowing waters over firm substrates. Such rheophilic, sand-and-rock habitats are typical of the genus.
Feeding
No detailed dietary study has been published for Harttia absaberi in the sources available here. FishBase lists an estimated trophic level of about 2.7, consistent with the broadly omnivorous, aufwuchs-grazing habits typical of small Loricariinae. Like its relatives, it almost certainly rasps biofilm, algae, and associated micro-invertebrates and detritus from the surfaces of sand grains, stones and submerged wood in its clear-water creek habitat. Specific aquarium feeding observations have not been documented.
Mating
No information on the courtship or mating behaviour of Harttia absaberi has been published in the sources reviewed. Members of the genus Harttia are generally substrate spawners in which the male guards the eggs, but no species-specific account exists for H. absaberi.
Breeding
No breeding has been documented for Harttia absaberi, in the wild or in aquaria, in the sources available here. The species has not established itself in the hobby and no captive reproduction reports are known. Many Harttia are reported to be lithophilous or substrate spawners with paternal egg-guarding, but applying that pattern to H. absaberi specifically would be speculation, and no data has been published.
In the aquarium
Harttia absaberi is essentially unknown in the aquarium trade, and no established husbandry guidance exists for it. Any keeping recommendations would be inferred from the requirements of similar small, rheophilic Harttia: a tank with strong, well-oxygenated flow, fine sand substrate, smooth rocks and clean, clear water at tropical temperatures. Given its small size and creek origins, it would suit a quiet biotope-style setup rather than a boisterous community. Because no genuine captive data is available, prospective keepers should treat all such guidance as provisional.
Conservation
The IUCN Red List assessed Harttia absaberi as Least Concern (assessment dated 18 May 2022). Despite its restricted occurrence in the upper rio Paraná drainage, the assessment found no evidence of significant population decline warranting a threatened category. The upper Paraná basin is nonetheless one of the most heavily modified river systems in Brazil, affected by extensive damming, agricultural runoff and urbanisation, so continued monitoring of small endemic stream fishes such as this one remains prudent.