Leporinus octofasciatus · Anostomidae · omnivore
The yellow piau with eight black stripes from the upper Paraná. Small, pretty and feisty on a cane pole and light rod.
Also called: piau-flamengo, flamenguinho, ferreirinha, piau-listrado, piava
Choose the place and the species. The index, from 0 to 100, combines weather, sun, moon and tide with each fish's habits. Up to 28 days, with each day's confidence.
Reading the weather across 3 global models and 31 simulations…
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.
Choose how many fishing days. We compare each stretch by its average index, discount days with a warning or closed season, and show the 3 best.
Line: the middle value of 31 simulations of the American GEFS model. Band: where 8 out of 10 fall. Narrow, firm trend; wide, high uncertainty.
A small piau from the upper Paraná and the Cubatão River in Santa Catarina, easy to recognize by the eight black bars on a yellow background. It eats plants and small invertebrates, and pairs spawn in dense vegetation. It lives in rivers and reservoirs, near rocks and vegetation, and bites on corn, dough and earthworm chum. It is also prized in the aquarium trade. In Goiás, in the Paranaíba basin, it has minimum and maximum size limits for capture.
Light yellow body with eight transverse black bars behind the head; reddish fins. Small mouth at the tip of the snout, with incisor teeth. The aracu-comum has only three or four stripes and is from the Amazon; the piau-três-pintas has spots, not bars.
Upper Paraná (Grande, Paranaíba, Tietê, Paranapanema and Paraná rivers) and the Cubatão River in Santa Catarina.
Habitat: Rivers and reservoirs, near rocks, submerged timber and aquatic vegetation.
native to the basins
states
São Paulo, Minas Gerais, Paraná, Goiás, Mato Grosso do Sul, Santa Catarina
Good from September to April; yields less in winter.
Daytime, with peaks at dawn and dusk. Active by day, with peaks early and late in the afternoon.
Strong cold leaves the fish inactive.
A cold front shuts down biting.
Little effect.
Little effect.
Stable river.
Wary in clear water.
Little effect.
Shallow, 0.5 to 3 m.
natural baits
accessories
Small hook and quick hookset: it nibbles like the other piaus.
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 national list (Portaria GM/MMA 1.667/2026).
In Goiás the piau-flamengo (Leporinus octofasciatus) may only be killed between 20 and 25 cm in the Paranaíba basin, and only for consumption on site.
Source: IN Semad-GO nº 17/2026, Annex I (in force May 28, 2026; on-site consumption only, zero transport)
Above 25 cm the piau-flamengo must be returned to the water in Goiás.
Source: IN Semad-GO nº 17/2026, Annex I (in force May 28, 2026; on-site consumption only, zero transport)
Allowed: Recreational fishing only for non-native species and hybrids (peacock bass, tilapia, black bass, carp, croaker, etc.; piauçu remains prohibited), with handline, simple pole, or rod with spinning or baitcasting reel, up to 10 kg + 1 fish. In rivers, from shore only; in reservoirs, from a boat or from shore. Prohibited: floodplain lakes, aquatic-animal bait, within 1,500 m of dams and waterfalls, and within 500 m of confluences. Tournaments only in reservoirs and only with non-native species.
Source: IN IBAMA nº 25/2009
Allowed: Only exotic or hybrid species, 3 kg + 1 fish per day, with handline, rod, simple pole, or spinning or baitcasting reel. Nets prohibited. Keep the minimum distances from dams and reservoirs.
Source: Portarias IEF nº 154/2011 (São Francisco), 155/2011 (East) and 156/2011 (Grande/Paranaíba)
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.
Allowed: Recreational fishing from a boat or from shore, with a single hook, one gear per angler, up to 5 kg.
Source: IN IBAMA nº 197/2008
Small fish: unhook it in the water and release it.
Small and bony; fried whole.
Length-weight relationship W = a·Lb (a = 0.01, b = 3.13; FishBase). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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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.
The weather comes from three independent global models, cross-checked hour by hour: when they agree, confidence goes up; when they diverge, the band between them shows on the chart. Beyond 16 days, we use the GEFS ensemble of 31 simulations: if 20 of the 31 predict rain, the chance of rain is 65%. Sun and moon are calculated astronomically, with no uncertainty.
The index adds up, weighted for each species: time of day (species curve anchored to real sunrise and sunset), moon (transits, rise and set, phase), pressure (3 h trend and 24 h swing), water temperature (in rivers, estimated from air temperature; at sea, estimated by an ocean model), wind, rain, clouds, tide and the month in the species' cycle.
Accuracy measured in the reference project (4 regions, 93 days, forecast vs. observed): maximum temperature is off by 0.6 °C on average the next day and 1.7 °C at 7 days; rain of 5 mm or more is detected 76% of the time the next day and 57% at 7 days. Detection isn't everything: the false alarm rate isn't published here yet, and 93 days in 4 regions is still a small sample. We now also measure every day, at the app's destinations:
Your location is saved only on this device and feeds the forecast, the map and the "today" on the home page.
