Closed season in Goiás (state rule)
01/11 to 28/02GO
Allowed: Sport and guided fishing only in reservoirs, catch and release with barbless hooks (no keeping, transporting or eating). Subsistence: up to 5 kg per day, for household consumption only.
catalog
Doradidae · omnivore
rebeca
Megalodoras uranoscopus
Freshwater
A large armored catfish of the slow-water rivers and lakes of the Amazon. It eats snails and fruit that fall into the water, migrates to spawn, and has strong spines on its pectoral fins. It turns up now and then in bottom fishing.
Also called: rebeca, bacu
- common size
- 35–50 cm
- maximum
- 53 cm
- common weight
- 0.5–1.5 kg
- record/max.
- 2.9 kg
- depth
- 1–10 m
- ideal water
- 24–28 °C
overview
who is the rebeca
Doradid, a catfish with spines and bony plates, reaching 53 cm standard length and 2.9 kg. It lives in the Amazon, Tocantins and Essequibo basins (Brazil, Bolivia, Colombia, Ecuador and Peru, per FishBase's country list) and was described from Lake Hyanuary, near Manaus. It seeks slow or still water, in tributaries, igarapés and swamps, sheltering among roots and submerged vegetation. It lives in small groups, sometimes forming shoals, and is mainly diurnal. It is omnivorous: it eats snails and fruit that fall into the water, such as those of Licania longipetala and jauari (Astrocaryum jauari). It makes seasonal migrations linked to spawning. It turns up in commercial fishing and, now and then, on the bottom hook of anglers fishing in the Amazon.
fun facts
- English-speaking aquarists call it the 'mother of snails' catfish because it eats large numbers of snails.
- The side plates and pectoral spines can catch in the net and cut the skin.
- It likes fruit that falls into the water, such as jauari fruit.
how to recognize it
identification
Elongated, robust body with a row of pointed bony plates along the middle of the flank, a broad, flattened head, three pairs of barbels and strong spines on the pectoral and dorsal fins. Females are larger and stockier than males. Among the doradids of the Amazon it is one of the largest; identify the species by its plates, spines and barbels together and, when in doubt, treat the fish as an armored catfish, taking care with the spines.
how rebeca fishing looks
Loading the next 7 days…
Each card shows the day's index (0 to 100) and, below it, a strip with the index for each hour, from 0h to 23h. from poor to excellent.
distribution
open on the large map where found
Rivers, igarapés and slow-water lakes of the Amazon and Tocantins basins, such as Lake Hyanuary, near Manaus (AM), where it was described. Outside Brazil, Bolivia, Colombia, Ecuador, Peru and the Essequibo basin.
Habitat: Slow or still water in tributaries, igarapés, swamps and lakes, among roots and submerged vegetation. It probably also uses main channels and flooded areas.
native to the basins
AmazonTocantins-Araguaia
states
Amazonas
when to fish
best season
time of yearbest: Aug–Nov
JanFebSeaAprMayJunJulAugSepOctNovDec
It makes seasonal migrations linked to spawning, on a poorly known schedule. In the dry season, with the river low, fish concentrate in pools and channels, and bottom fishing is best then.
best time of day
Daytime. Mainly diurnal, according to FishBase, in small groups that move among roots and vegetation.
what affects the rebeca
sensitivity The little bars show how much each factor affects this species. Five full: it feels it a lot.
sensitivity The little bars show how much each factor affects this species. Five full: it feels it a lot.
cold and cold fronts
Cold spells (friagem) reduce activity for a few days.
atmospheric pressure
Little effect.
moon
Small effect.
rain
Heavy rain muddies the water and scatters the fish, but the species already lives in dark water.
water level
A falling river and dry season concentrate fish in pools and channels; at high water it spreads through the flooded area.
noise
Moderate: avoid knocking the hull.
wind
Little effect on the bottom.
depth
Bottom of pools and banks with roots, 2 to 8 m.
how to fish
- rod
- 6'6" to 7', medium-heavy action, 20 to 40 lb
- spinning / baitcasting reel
- 5000 to 6000 spinning reel or low-profile baitcaster 300
- line
- braid 30 to 50 lb
- leader
- heavy monofilament 0.60 to 0.80 mm, 60 cm: the bony plates wear through the line
- hook
- 3/0 to 6/0, forged, hooks in the corner of the mouth
natural baits
- forest fruit
- caramujo
- minhoca
- fish pieces
accessories
- thick gloves
- long-nose pliers
- boga-grip
tip from an angler
Ripe fruit or a snail on the bottom, next to roots, and set the hook firmly. Once the fish is hooked, avoid contact with its body: plates and spines cut.
rules for the rebeca
Summary of the regulations we found, with the source for each. Rules change; before keeping or transporting fish, check with the state environmental agency.
Conservation: Not on the Brazilian national list (Ministerial Ordinance GM/MMA No. 1.667/2026).
We found no species-specific rule beyond the region's general rules.
piracema closures in the basins where the species lives
Spawning closure (piracema) in Mato Grosso (all basins)
01/10 to 31/01MT
Allowed: All fishing modalities are prohibited in rivers, including catch and release (Law 9.096/2009, art. 19-A). Exceptions: subsistence fishing from shore (3 kg or 1 fish, no transport or sale) and scientific fishing. Law 13.159/2025 now allows licensed sport fishing in UHE/PCH hydropower reservoirs, natural lakes and border rivers, subject to a scientific study and a license from the environmental agency. We have not confirmed whether these licenses are already being issued.
Spawning closure (piracema) in the Araguaia River basin
01/11 to 28/02GOTOPAMT
Allowed: Recreational fishing only in reservoirs, with handline, rod, or spinning or baitcasting reel. Fish may only be eaten on site, not transported. Competitions prohibited. Subsistence: 3 kg + 1 fish. State rules (GO and TO) may be stricter.
Spawning closure (piracema) in the Tocantins and Gurupi river basins
01/11 to 28/02TOPAMAGO
Allowed: Recreational fishing only in reservoirs, with on-site consumption. Subsistence: 5 kg + 1 fish. State rules may be stricter.
Spawning closure (piracema) in Tocantins (state rule)
01/11 to 28/02TO
Allowed: In 2025/26: catch and release with barbless hooks and recreational fishing card; subsistence fishing on foot or from a rowboat, with simple pole or handline.
Source: Portaria Naturatins nº 244/2025 (2025/26 season); INIs MPA/MMA nº 12 and 13/2011
Closed season in the rivers of Marajó Island (PA)
01/01 to 30/04PA
Allowed: The same recreational-angler exceptions as in Portaria 48/2007 apply (handline or rod, 5 kg + 1 fish), unless a stricter state rule applies.
Source: Portaria IBAMA nº 48/2007
Closed season in the Amazon basin in Amapá
15/11 to 15/03AP
Allowed: Recreational anglers with handline or rod, line and hook are outside the Annex II prohibitions, with a bag limit of 5 kg + 1 fish, unless a stricter state rule applies.
Source: Portaria IBAMA nº 48/2007
Closed season in Roraima
01/03 to 30/06RR
Allowed: Subsistence fishing only.
Source: Portaria IBAMA nº 48/2007
Border rivers MT/RO and MT/PA
05/11 to 28/02MTROPA
Allowed: See the exceptions in Portaria 48/2007 and the state rules for each bank.
Source: Portaria IBAMA nº 48/2007
catch and release
catch and release Releasing the fish alive, quickly and with a wet hand. During a closed season it isn't always allowed: what the regulation says applies.
catch and release Releasing the fish alive, quickly and with a wet hand. During a closed season it isn't always allowed: what the regulation says applies.
Use thick gloves and hold the fish firmly by the body, away from the pectoral and dorsal spines and the side plates, which cut. Remove the hook with long pliers and release slowly, in water with little current.
in the kitchen
It shows up in commercial fishing. The thick skin and bony plates call for careful cleaning; the meat is catfish-type, good in caldeirada.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.0123, b = 3.0; FishBase (relação peso-comprimento bayesiana, estimativa da própria espécie)). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
—
sources and references
The season weights (months), the time of day and the sensitivities (cold, pressure, moon, wind, rain, tide, strong light, murky water and noise) are the app's editorial estimates, based on the literature below and on the field experience of anglers and guides. They are not official data nor a measurement made for this species, and they may vary by region and year. Closed seasons and legal rules appear in the rules section, with the norm and a link.
- scientific FishBase: Megalodoras uranoscopus (ficha da espécie)Size, length-weight relationship, depth, habitat, distribution, biology and IUCN status. Page checked on October 13, 2026. The common size (FishBase gives 49 cm standard length) and the common weight and depth range are editorial estimates for sport fish; the maximum length of 53 cm and the weight of 2.9 kg are as published. The color pattern follows that of doradids in general, because we found no published description of this species' coloration.
- scientific FishBase: nomes populares de Megalodoras uranoscopusNames by country and language.
- official Portaria GM/MMA nº 1.667, de 27 de abril de 2026: Lista Nacional Oficial de Espécies da Fauna Ameaçadas de Extinção (peixes e invertebrados aquáticos)The species is not on the list. Checked in the DOU of April 28, 2026.
- technical Seriously Fish: Megalodoras uranoscopusSlow-water habitat, omnivorous diet (snails and fruit), group behavior, migrations linked to spawning and differences between the sexes. Page checked on October 13, 2026.
