Taxonomy & naming
Rineloricaria nudipectoris was described by Mejia, Ferraro and Buckup in 2023, in Neotropical Ichthyology (21(1): e220083), in a paper describing a new species of Rineloricaria from coastal drainages of Rio de Janeiro, southeastern Brazil. The Catalog of Fishes (Eschmeyer, CAS) lists it as valid (CoF species id 77273); the authority carries no parentheses because the species was originally placed in Rineloricaria.
The species belongs to the subfamily Loricariinae, the whiptail catfishes, within the suckermouth-armoured catfish family Loricariidae. The species epithet nudipectoris derives from the Latin nudus (bare) and pectus (breast), referring to the absence of plates on the ventral surface of the pectoral girdle.
Morphology
Rineloricaria nudipectoris reaches a maximum recorded length of about 4.5 in standard length (male/unsexed). It has the typical Rineloricaria form: an elongated, dorsoventrally flattened body tapering to a slender whip-like tail. The dorsal fin has 7 soft rays and the anal fin 5 soft rays.
The species is diagnosed by a combination of features: the absence of plates on most of the ventral surface of the pectoral girdle and abdominal region; an anterior snout area of exposed skin without odontodes that extends laterally to the most anterior pore of the infraorbital ramus; the upper unbranched caudal-fin ray extended as a short filament; the leading-edge pectoral-fin ray reaching the pelvic-fin origin; and a spotted colour pattern on the dorsal, pectoral and pelvic-fin rays.
No information on sexual dimorphism is provided in the available reference data.
Habitat
Rineloricaria nudipectoris is known from coastal drainages of Rio de Janeiro state, southeastern Brazil. It is a freshwater, demersal fish of tropical waters. More detailed microhabitat data — substrate, current, and water chemistry — are not published in the available sources.
Feeding
No dedicated feeding study for Rineloricaria nudipectoris is available. FishBase lists a trophic level of approximately 2.6, consistent with the omnivorous-to-detritivorous grazing typical of whiptail loricariins, which rasp biofilm, algae, fine detritus, and small invertebrates from hard surfaces. Captive dietary requirements are not documented.
Mating
No data on courtship or mating behaviour have been published for Rineloricaria nudipectoris.
Breeding
No breeding records exist for Rineloricaria nudipectoris in the available sources. Whiptail loricariins as a group are generally substrate- or cavity-spawners with paternal egg care, but this has not been confirmed for this species and should not be assumed.
In the aquarium
As a species described only in 2023, Rineloricaria nudipectoris is not present in the aquarium hobby, and no husbandry information exists. General care of small Rineloricaria whiptails calls for clean, well-oxygenated water, a fine substrate, moderate current, and biofilm-rich grazing surfaces, but no species-specific guidance can be offered responsibly here.
Conservation
Rineloricaria nudipectoris has not yet been evaluated by the IUCN Red List (Not Evaluated). As a recently described species with an apparently restricted distribution in coastal drainages of Rio de Janeiro state — a heavily urbanised and industrialised region of southeastern Brazil — its conservation status warrants future assessment, but no formal designation currently exists.