torroto grunt
Genyatremus luteus · Haemulidae · predator
The tall, silver pigfish of the estuaries of the North and Northeast, traditional in Maranhão and Pará. It takes shrimp on the bottom of the channels and has fine flesh.
Also called: peixe-pedra, golosa, gulosa, coró-branco, sanhoá, caicanha
- common size
- 18–28 cm
- maximum
- 37 cm
- common weight
- 0.1–0.5 kg
- record/max.
- 0.8 kg
- depth
- 1–20 m
- ideal water
- 26–30 °C
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
slide your finger or mouse over the chart to see each hoursee 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 torroto grunt
who is the torroto grunt
The peixe-pedra is a grunt with a deep body that lives mainly in brackish estuaries and nearby areas, over sand and mud bottoms, from Venezuela to Brazil, down to about 40 m; it sometimes appears in open sea. It is heavily fished and eaten in Pará and Maranhão, in fish corrals, nets and handlines. It eats crustaceans. It grows to 37 cm and 800 g, with the usual size around 25 cm. On the hook it takes shrimp and pieces of fish close to the bottom, near rocks and in estuary channels. Part of the Brazilian literature, including the ICMBio assessment, uses the name Genyatremus cavifrons for it, now treated as a synonym of G. luteus in the Catalog of Fishes.
fun facts
- Like other pigfish, it grunts when taken out of the water.
- The syntypes of Genyatremus cavifrons, a name now treated as a synonym, were collected in Rio de Janeiro.
identification
Short, deep, compressed body, almost disc-shaped, silvery to light gray. Small mouth. Continuous dorsal fin with 13 spines and 12 soft rays; anal fin with 3 spines and 11 rays. It differs from the red pigfish (corcoroca-verdadeira), which is more elongated and orange-painted, and from the sargo-de-beiço and salema, which have well-marked bands or stripes.
where found
Estuaries of the North and Northeast, especially Pará and Maranhão; the Catalog of Fishes lists the species as far as Rio Grande do Sul, but outside the North and Northeast it is rarely recorded in fishing. Outside Brazil, from the Guianas to Venezuela and the southern Caribbean.
Habitat: Brackish estuaries and nearby areas, over sand and mud, near rocks, fish corrals and channels.
coast
states
Amapá, Pará, Maranhão, Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe, Bahia
when to fish
best season
Found all year; in the estuaries of Maranhão and Pará, the dry season in the second half of the year usually produces more on the line.
best time of day
Daytime, with peaks at dawn and dusk. Bites by day and late in the afternoon, mostly on the rising tide, near the bottom and rocks.
what affects the torroto grunt
sensitivity The little bars show how much each factor affects this species. Five full: it feels it a lot.
cold and cold fronts
No significant effect on the tropical coast.
atmospheric pressure
Not very sensitive; settled weather helps fishing from a canoe.
moon
Spring tides at new and full moon bring more current and more food.
rain
Heavy rain that sweetens the estuary scatters the schools.
water level
In the dry season the estuary becomes saltier and the fish move up with the tide.
noise
Moderate in shallow water: anchor away from the spot and cast.
wind
Strong wind makes it hard to feel the bite; look for sheltered banks.
tide
Fish the flood tide; at slack tide the bites slow down.
depth
1 to 8 m in channels and along banks.
how to fish
- rod
- 1.8 to 2.1 m (6' to 7'), 6 to 14 lb, or cane pole
- spinning / baitcasting reel
- spinning reel 1000 to 3000
- line
- monofilament 0.20 to 0.28 mm
- leader
- fluorocarbon 0.28 to 0.35 mm
- hook
- small hooks, sizes 4 to 1
natural baits
- shrimp
- sururu
- fish pieces
accessories
- olive sinker, 10 to 30 g
- landing net
tip from an angler
A small mouth calls for a small hook and well-secured bait; wait for the second tug before setting the hook.
rules for the torroto grunt
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 assessed by the IUCN as G. luteus, according to FishBase. Not on the national list (Portaria GM/MMA 1.667/2026). ICMBio assessed the Brazilian form under the name Genyatremus cavifrons. We found no specific federal rule for the species.
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.
Hardy fish: remove the hook quickly and release it in the water. Watch out for the dorsal spines.
in the kitchen
White, fine, tasty flesh, much prized fried whole in Maranhão and Pará.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.01778, b = 2.96; FishBase (estimativa bayesiana com dados da espécie e da subfamília, comprimento total)). 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 — Genyatremus luteus (ficha da espécie)Names, distribution, biology, length-weight relationship, country list and references. Page checked on 13/10/2026. FishBase also keeps a separate entry for Genyatremus cavifrons, with few data.
- scientific Eschmeyer's Catalog of Fishes — gênero Genyatremus (espécies, sinônimos e distribuição)Treats Genyatremus cavifrons as a synonym of G. luteus (Parenti, 2019) and gives the distribution from Venezuela to Rio Grande do Sul. Checked on 13/10/2026.
- 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 Genyatremus cavifrons (avaliação nacional do risco de extinção)National extinction risk assessment by ICMBio, published in 2025. DOI checked on Crossref. ICMBio uses the name G. cavifrons for the Brazilian form.
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: