Taxonomy & naming
Dentectus barbarmatus was described by Martín Salazar, Isbrücker and Nijssen in 1982, in Beaufortia (volume 32, number 8, page 130, with figures 1–5). It is the only species in the genus Dentectus, which is monotypic, and the name carries no synonyms. The type locality is the Río Salinas, a tributary of the Río Pao Viejo, northeast of El Baúl (approximately 9°13'N, 68°07'W), in Estado Cojedes, Venezuela.
The species belongs to the subfamily Loricariinae. Its generic name reflects the most striking feature of the fish — Dentectus signifies a 'tooth-bearer', referring to dentary teeth that are atypical for the subfamily.
Morphology
Dentectus barbarmatus reaches 5.5 in standard length (the type material recorded at 5.5 in SL). The fish is distinguished within the Loricariinae by two features: a barbel-bearing snout, and dentary teeth that are unusual for the subfamily — together the basis for the names Dentectus ('tooth-bearer') and barbarmatus ('armed with barbels'). No further detailed morphometric data is published in the secondary sources consulted.
Habitat
Dentectus barbarmatus is found in the western Orinoco River basin of Venezuela, in the Cojedes and Portuguesa–Apure llanos drainages. The type series came from the Río Salinas, a tributary of the Río Pao Viejo in Estado Cojedes. It is a freshwater, demersal fish of tropical waters. No published water-chemistry or depth data is available for the species.
Feeding
No published diet notes exist for Dentectus barbarmatus.
Mating
No data has been published on courtship or mating behaviour in Dentectus barbarmatus.
Breeding
No breeding report exists for Dentectus barbarmatus.
In the aquarium
Dentectus barbarmatus is essentially absent from the aquarium trade, and no husbandry information has been published for the species.
Conservation
The IUCN Red List assessed Dentectus barbarmatus as Least Concern in 2020. The species is widespread across the western Venezuelan llanos of the Orinoco basin, and no major range-wide threats have been identified.