aracu
Leporinus granti · Anostomidae · omnivore
Small aracu from rivers of French Guiana and Guyana, up to 20 cm. It occasionally turns up on the line, especially with a small hook.
Also called: aracu, sardina
- maximum
- 20 cm
- record/max.
- 0.2 kg
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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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 —?
choose 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.
the fishing month at a glance
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.
everything about the aracu
who is the aracu
The aracu is a freshwater anostomid of the same group as the piaus, reaching 20 cm and 185 g. It occurs in rivers of the Mana basin, in French Guiana, and in Guyana. Adults gather in large numbers at the mouths of streams, over sand or mud bottoms, and young ones stay in calm, shallow waters near plants. It is omnivorous and digests chitin, present in insects and crustaceans. It breeds from December to June. As it is easily hooked with a small hook, it turns up in river fishing, but it is not a trophy fish.
Essential profile. Identification, where it occurs and rules, with data from FishBase and the cited regulations. Season, time of day, technique and bait are added once we have a good source for the aracu; in the meantime, see the similar species.
fun facts
- Aquarists consider it restless in captivity.
identification
Elongated anostomid, with a small mouth and incisor-like teeth, typical of the piaus and aracus. The name aracu applies to several species, so confirm the region: this one lives in the rivers of French Guiana and Guyana. It may be confused with the lipstick leporinus (piau-batom), of the same group, which also occurs in the Guianas.
where found
Rivers of the Mana basin, in French Guiana, and rivers of Guyana. Not recorded in Brazil.
Habitat: Adults at the mouths of streams, over sand or mud bottoms; juveniles in calm, shallow waters, near plants.
rules for the aracu
Summary of the regulations we found, with the source for each. Rules change; before keeping or transporting fish, check with the state environmental agency.
We found no species-specific rule beyond the region's general rules.
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.
Small fish of the current: hold it with a wet hand, carefully remove the hook from its small mouth, and return it quickly.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.01072, b = 3.11; 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
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sources and references
Essential profile: size, length-weight, depth, countries and conservation come from FishBase and the cited regulations, and the texts were written from those sources. Season, time of day, sensitivities, technique and baits and lures are not included yet, because we did not find a good source for this species.
- scientific FishBase: Leporinus granti (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Leporinus grantiNames by country and language.
similar species
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: