Paraná basin: minimum 40 cm
40 cmSPPRMGGOParaná
Federal minimum size for piapara/piau-verdadeiro in the Paraná basin.
Source: Instrução Normativa Ibama nº 26/2009 (fishing rules for the Paraná River basin), Annex
fishing forecast
piapara
Megaleporinus obtusidens · Anostomidae · omnivore
Freshwater
The queen of chum fishing on the Grande and Paranaíba rivers. Nibbles delicately, demands a quick hookset and fights hard for its size.
Also called: piapara, piau-verdadeiro, boga, piau
- common size
- 35–55 cm
- maximum
- 76 cm
- common weight
- 1–3 kg
- record/max.
- 5.8 kg
- depth
- 2–10 m
- ideal water
- 22–28 °C
fishing forecast
the right time
the right time
to be on the water
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…
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index Score from 0 to 100 for the fishing conditions of each hour. It reads weather, sun, moon, tide and the species' habits. It doesn't promise fish: it tells you when the water is on your side. 0–24 poor · 25–44 fair · 45–64 good · 65–84 very good · 85–100 excellent.
today
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confidence —
confidence How much you can trust the weather forecast for the day. It drops with distance and when the models disagree. It is not the chance of catching fish.
models and trend Up to 16 days, three global weather models (the European ECMWF, the American GFS and a high-resolution blend) read hour by hour; when they disagree, the light band on the chart widens. Beyond that it's a trend: 31 runs of the American GEFS model. Confirm when it's 1 week out.
window Consecutive hours with the index near the day's peak and no danger alert. It is the time to have the bait in the water.
hour by hour
tap or drag on the chart to read each hour · on a keyboard, arrow keyssee hour-by-hour table
why this index at —?
next 7 days
chart: bar height = day's index · line = variation between models · striped = trend · fainter = less confidencechoose the day
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.
4-week calendar
the fishing month at a glance
plan a trip
what's the best window for the crew?
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.
trend for the coming weeks
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.
the species
everything about the piapara
overview
who is the piapara
A large, silver piau from the Plata and São Francisco rivers. It lives in schools near the bottom and eats seeds, grains, algae, mollusks and insects. In the Grande and Paranaíba reservoirs it became the star of corn chum fishing. The bite is delicate and quick: the piapara nibbles the bait and lets go. Anglers with slack line don't hook up. Once hooked, it dashes hard for the bottom. At 2 to 3 kg it is already a highly respected fish. In the Paraná basin the minimum is 40 cm.
fun facts
- Corn chum for piapara is a tradition on the Grande River, between MG and SP.
- In Rio Grande do Sul and Argentina it is called boga.
how to recognize it
identification
Elongated, silver body, greyish-green back, with three rounded dark spots along the lateral line. Small, nearly inferior mouth with strong incisor teeth. The piavuçu has a much larger head and greenish body. The piau-três-pintas is smaller, with more marked spots and a more yellowish body.
distribution
open on the large map where found
Reservoirs and rivers of the upper Paraná (Grande, Paranaíba, Tietê, Paranapanema, Paraná), Pantanal, Uruguay River and São Francisco.
Habitat: Sand and gravel bottoms in backwaters, reservoir channels, island points and banks; concentrates at chummed spots.
native to the basins
ParanáParaguay (Pantanal)UruguaySão Francisco
states
São Paulo, Minas Gerais, Goiás, Paraná, Mato Grosso do Sul, Rio Grande do Sul, Santa Catarina
when to fish
best season
time of yearbest: Mar–Apr and Oct
JanFebSeaAprMayJunJulAugSepOctNovDec
March to May and September to October are best. Cold winter calls for a longer chum session.
best time of day
Daytime, with peaks at dawn and dusk. Best early morning and late afternoon; on a well-built chum, it feeds all day.
what affects the piapara
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
Water below 20 °C greatly reduces activity.
atmospheric pressure
After a cold front the piapara disappears from the chum for 1 to 2 days.
moon
Small effect.
rain
Light rain doesn't bother it.
water level
In reservoirs, stable level. A rapid drop in level scatters the school.
noise
Wary. Anchor away from the chum and avoid knocking the boat.
wind
Strong wind bellies the line and hides the nibble.
depth
Bottom, 3 to 8 m, at the chummed spot.
how to fish
- rod
- 6' to 7', fast action and sensitive tip, 8 to 20 lb
- spinning / baitcasting reel
- spinning reel 2500 to 3000
- line
- braided line 15 to 20 lb (feels the nibble better) or monofilament 0.30 mm
- leader
- fluorocarbon 20 to 25 lb, 50 cm
- hook
- #1 to 1/0, short, chinu or maruseigo type
natural baits
- green corn
- boiled corn
- cornmeal dough (fubá)
- minhoca
- boiled soybean
accessories
- sour or cooked corn chum
- olive sinker 10 to 30 g
- alicate
tip from an angler
Keep the line taut and the rod in hand. The nibble is quick: set the hook short on the first firm touch.
rules for the piapara
Summary of the regulations we found, with the source for each. Rules change; before keeping or transporting fish, check with the state environmental agency.
MG: 40 cm for piapara
40 cmMG
The Minas Gerais ordinance sets 40 cm for piapara (Leporinus elongatus) and 25 cm for the "piau" L. obtusidens. Since identification is difficult, respect 40 cm.
Source: Portaria IEF-MG nº 111/2003 (minimum catch sizes in MG) - IEF/Semad-MG
Minimum size: 40 cm
SPPRMGGOMSDFParaná
Source: IN IBAMA nº 26/2009, Annex (Paraná River basin; stricter state rules prevail)
Minimum size: 40 cm (max. 60 cm)
PRParanáSoutheast Atlantic
Source: Portaria IAT nº 650/2025, Annex I (interior basins of PR, except Iguazu and coastal)
Minimum size: 40 cm
MG
Minimum size: 35 cm (max. 45 cm)
GOParaná
Source: IN Semad-GO nº 17/2026, Annex I, Paranaíba basin (on-site consumption only; zero transport)
piracema closures in the basins where the species lives
Spawning closure (piracema) in the Paraná River basin
01/11 to 28/02SPPRMGGOMSDF
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
Spawning closure (piracema) in Minas Gerais (state rule)
01/11 to 28/02MG
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)
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.
Spawning closure (piracema) in the Pantanal of Mato Grosso do Sul
05/11 to 28/02MS
Allowed: Subsistence fishing by riverside residents and authorized scientific fishing. Decree 15.166/2019 (art. 11, §5) allows catch and release only in February and only in the channels of the Paraguay and Paraná rivers. For the rest of the period, not even catch and release is allowed. Check the Imasul portaria for each season.
Source: Decreto estadual MS nº 15.166/2019, art. 11; IN IBAMA nº 201/2008
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 São Francisco River basin (rivers and reservoirs)
01/11 to 28/02MGBAPEALSEGODF
Allowed: Recreational fishing from a boat or from shore with handline, rod, spinning or baitcasting reel, up to 5 kg + 1 fish. Prohibited within 1,000 m of dams, waterfalls and rapids, and within 500 m of confluences. Floodplain lakes have a longer closed season (see next item).
Source: Portaria IBAMA nº 50/2007
São Francisco: floodplain lakes
01/11 to 30/04MGBAPEALSEGODF
Allowed: No fishing in the floodplain lakes during the period.
Source: Portaria IBAMA nº 50/2007
Spawning closure (piracema) in the Uruguay River basin
01/10 to 31/01RSSC
Allowed: Recreational fishing from shore, or from a boat without motor. Only handline or rod, line and hook, one gear per angler, up to 5 kg. Prohibited in floodplain lakes, within 1,500 m of dams, within 500 m of confluences, and in stretches listed in the rule (e.g., Turvo River).
Source: IN IBAMA nº 193/2008
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.
Remove the hook with pliers, hold it horizontally and return it quickly.
in the kitchen
White, tasty flesh with bones; fried in thin steaks or grilled over coals.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.01175, b = 3.08; FishBase). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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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 — Megaleporinus obtusidens (ficha da espécie)Names, distribution, biology, length-weight relationship and references. Page checked on October 13, 2026.
- 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)Most recent national list. The species is not on it (search by scientific name in the text published in the DOU, checked on October 13, 2026).
- official ICMBio/SALVE — Ficha de Megaleporinus obtusidens (avaliação nacional do risco de extinção)National assessment by ICMBio, published in 2024. DOI verified on Crossref.
- scientific IUCN Red List — Megaleporinus obtusidens (avaliação global: Pouco Preocupante, LC, 05/09/2020)Global assessment. Link given on the FishBase entry (Red List, version 2025-2).
- scientific Ramirez, J. L.; Birindelli, J. L. O.; Galetti Jr., P. M. (2017). A new genus of Anostomidae (Ostariophysi: Characiformes): diversity, phylogeny and biogeography based on cytogenetic, molecular and morphological data. Molecular Phylogenetics and Evolution 107: 308–323.Creates the genus Megaleporinus (formerly Leporinus).
- scientific Ota, R. R.; Deprá, G. C.; Graça, W. J.; Pavanelli, C. S. (2018). Peixes da planície de inundação do alto rio Paraná e áreas adjacentes: revised, annotated and updated. Neotropical Ichthyology 16(2): e170094.Annotated list of species of the upper Paraná River, indicating native and non-native ones. Open access; species name checked in the text.
- scientific Zaniboni Filho, E.; Meurer, S.; Shibatta, O. A.; Nuñer, A. P. O. (2004). Catálogo ilustrado de peixes do alto rio Uruguai. Florianópolis: Editora da UFSC; Tractebel Energia. 128 p.Printed work; the URL is the bibliographic record on FishBase, which cites this work for the species.
similar species
how we calculate
where each number comes from
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.
sources for this lookup
how accurate the forecast is
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: