Taxonomy & naming
Tatia caudosignata was described in 2019 by Carlos DoNascimiento, Douglas Albornoz-Garzón and Javier García-Melo, based on specimens collected from a terra firme stream in the western Amazon basin of Colombia. It belongs to the family Auchenipteridae, the driftwood catfishes, within the genus Tatia — a group of small, slender South American catfishes distinguished from their larger relatives by their diminutive size and internal-fertilisation breeding biology.
The genus name Tatia is a name of South American origin applied to this group of small auchenipterids; the species epithet caudosignata derives from Latin cauda ("tail") and signatus ("marked, signed"), referring to the distinctive narrow white bilobed band at the base of the caudal fin that distinguishes this species from its close relatives. As a species described in 2019, it has not accumulated a history of generic reassignment — it was named directly into Tatia and the Catalog of Fishes treats it as valid there.
Morphology
Tatia caudosignata is a small catfish: the type series, two specimens collected at the type locality, measured 3.5–4 in standard length, giving a practical adult size of roughly 4 in SL. As in all driftwood cats the skin is entirely scaleless (naked), which matters for medication dosing (see "In the aquarium").
Coloration is the species' clearest field mark: the body is dark dorsally, fading to a paler tone ventrally, with a mostly dark dorsal fin. The name-bearing feature is a narrow, white, bilobed band crossing the base of the caudal fin — a marking that separates this species from other similarly patterned Tatia. Like other auchenipterids, males carry a modified anal fin (used as an intromittent organ in mating) that differs in shape from the female's, a useful cue for sexing mature fish.
Habitat
The species is known from terra firme streams in the western Amazon River basin of Colombia — small, forest-shaded headwater and tributary streams away from the seasonally flooded floodplain, running over sandy or leaf-litter substrates. The type locality is Quebrada Sufragio, a tributary of the río Pureté in Amazonas department, Colombia.
Auchenipterid driftwood cats of this kind typically inhabit oligotrophic, soft, acidic clear- or blackwater streams in warm tropical conditions, generally in the range of roughly 73–81 °F. Most species in the genus, including this one, occupy narrow, specialised niches within these headwater systems and are rarely encountered outside them.
Feeding
As a driftwood catfish, Tatia caudosignata is a nocturnal benthic omnivore and micro-predator, foraging over the streambed after dark for aquatic invertebrates, detritus and small prey items rather than actively hunting fish. This matches the feeding ecology documented across the genus Tatia and the wider Auchenipteridae.
In an aquarium setting, driftwood cats of this type accept sinking foods such as tubifex and prepared pellets once acclimated, and — because they feed mainly at night — do best when food is offered after the lights go out so they are not out-competed by diurnal tankmates. No aquarium-specific feeding data exists for this particular species; the above follows documented Tatia care generally.
Mating
Tatia caudosignata shares the unusual reproductive biology of its family: Auchenipteridae is one of the few catfish groups with internal fertilisation. In males, the anal fin is modified into an intromittent organ used to transfer sperm directly to the female during mating, rather than the pair releasing eggs and milt into open water as most catfishes do.
Following mating, the female stores the sperm internally and can lay a fertile clutch of eggs some time later, decoupling copulation from spawning. This strategy is rare among catfishes as a whole and is a defining trait of the driftwood cats; it has not been documented in detail for this specific, recently described species, but is characteristic of the genus Tatia and the family it belongs to.
Breeding
No aquarium spawning of Tatia caudosignata has been documented — as a species described only in 2019 from a narrow patch of Amazonian habitat, it is essentially unknown in captivity. Breeding biology can be inferred from the family: internal fertilisation via the modified male anal fin, with the female storing sperm and depositing fertile eggs later, generally with little or no parental care once the eggs are laid.
Other Tatia species kept in aquaria have occasionally been coaxed to spawn using cave-like retreats (bamboo tubes, driftwood crevices) alongside heavy feeding and a temperature drop followed by a rise to simulate a rain event, but there is no record of this being attempted with T. caudosignata specifically. Prospective keepers should treat any breeding attempt as unproven territory rather than a routine project.
In the aquarium
Tatia caudosignata is not established in the aquarium trade and no husbandry record exists for the species specifically; the following is drawn from care of the genus Tatia generally and should be treated as a starting point, not a confirmed protocol. At a modest adult size around 4 in SL, it would not need an especially large tank by catfish standards, but as with any driftwood cat the real adult size should be respected rather than assumed to stay tiny.
Being entirely scaleless, it is medication-sensitive — copper-based treatments and many standard medications should be dosed conservatively, often at half strength, as with loaches, puffers and eels. It is nocturnal and will want dense cover (driftwood, bamboo tubes, leaf litter) to retreat into by day, emerging to feed after dark. Given its terra firme stream origin, soft, acidic, warm water in the 73–81 °F range is the reasonable target, though exact parameter tolerances for this species have not been published. This is a fish for the specialist prepared to work from genus-level husbandry rather than a proven care sheet.
Conservation
Tatia caudosignata has not been evaluated by the IUCN Red List; its status is Not Evaluated. This is unsurprising for a species described as recently as 2019 from a single documented locality in the Colombian Amazon — formal assessment typically lags well behind description for narrowly known Neotropical catfishes.
With only a type locality and no broader distributional survey on record, its true range and any pressures on it (deforestation, stream degradation, or headwater habitat loss in the western Amazon) are not well characterised. As with many recently described, single-river catfishes, the honest summary is that too little is currently known to assess conservation status with confidence.