Taxonomy & naming
Hopliancistrus munduruku was described by de Oliveira, Zuanon, Rapp Py-Daniel, Birindelli and Sousa in 2021, in PLoS ONE volume 16, number 1, article e0244894 — a taxonomic revision of the genus Hopliancistrus Isbrücker & Nijssen, 1989, which redescribed the type species H. tricornis and named four new species. The Catalog of Fishes (Eschmeyer, CAS) recognises Hopliancistrus munduruku as valid; the authority is written without parentheses, indicating an original combination that has not been moved between genera.
The species belongs to the subfamily Hypostominae, tribe Ancistrini — the bristlenose and relatives clade. The genus name combines the Greek hoplon ("weapon") with agkistron ("hook"), a reference to the strong hooked cheek odontodes that arm members of the genus.
Morphology
Hopliancistrus munduruku reaches about 6 in standard length (SL). Meristic counts from the description include two dorsal-fin spines, seven dorsal soft rays, five anal soft rays, and 28 vertebrae; the body has an angular cross-section.
The defining feature of the genus is its armament of strong, hooked odontodes on the cheeks (interopercle) — the "hook-armed" character behind the generic name. As in most Ancistrini, these evertible cheek spines are presumed to function in defence and in male-male interactions. Detailed sexual-dimorphism data specific to this species are not reported in the accessible sources.
Habitat
Hopliancistrus munduruku occurs in Brazil, in the Rio Tapajós basin of southwestern Pará State — the region of the Munduruku indigenous people for whom it is named, and consistent with the overall Tapajós-basin distribution of the genus. It is a freshwater, demersal, tropical species.
Members of the genus are typically associated with rocky, fast-flowing clearwater habitats of the Tapajós and its tributaries. Specific water-chemistry measurements (temperature, pH, hardness) for this species are not published in the accessible literature.
Feeding
No detailed feeding study has been published for Hopliancistrus munduruku, and dietary information is sparse in the accessible sources. As an ancistrine loricariid of rocky clearwater rivers, it is presumed to graze the aufwuchs — the biofilm of algae, micro-invertebrates, and detritus — on submerged rock surfaces, in line with the feeding habits of related genera, but no species-specific data confirm this.
Mating
No courtship or mating behaviour has been documented for Hopliancistrus munduruku. The hooked cheek odontodes characteristic of the genus may play a role in male competition or display, as they do in other Ancistrini, but no observations of mating in this species have been published.
Breeding
No breeding report exists for Hopliancistrus munduruku. Its reproductive mode, clutch size, spawning site, and any parental care are unknown. Many Ancistrini are cave-spawners with paternal egg-guarding, but this has not been confirmed for the species, and no captive-breeding data are available.
In the aquarium
Hopliancistrus munduruku is a recently described species (2021) with little to no presence in the aquarium hobby; husbandry data are not published. As a Tapajós-basin ancistrine of presumed rocky, fast-flowing clearwater habitat, it would in principle require warm, clean, well-oxygenated water with strong flow and rocky cover were it to be kept — but any such guidance is extrapolated from related fishes rather than documented for this species, which remains primarily of scientific interest.
Conservation
Hopliancistrus munduruku has not been evaluated by the IUCN Red List (status: Not Evaluated). As a species described only in 2021 from the Rio Tapajós basin, it lacks a formal conservation assessment. The Tapajós basin faces well-documented pressures from hydroelectric development, mining, and deforestation, which alter river flow, sedimentation, and water quality; these broader threats are relevant to the rheophilic, rock-dwelling fishes of the system, though no species-specific population data are available to gauge its status.