smallmouth silverside
Chirostoma chapalae · Atherinopsidae · forage fish
Small silverside from Lake Chapala and the Lerma basin, in Mexico, up to 14 cm. Like other silversides, it forms schools. It is caught commercially.
Also called: peixe-rei-de-boca-pequena, charal de Chapala, charal, smallmouth silverside
- maximum
- 14 cm
- record/max.
- 0.0 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 smallmouth silverside
who is the smallmouth silverside
The smallmouth silverside is a fish of the family Atherinopsidae, a relative of the marine silversides, reaching 14 cm and 12 g. It is endemic to the Lerma River basin, in central Mexico, and lives in fresh water, between midwater and the bottom. Like other silversides, it forms schools and is food for larger fish. It is caught commercially and is not sought by sport anglers using rod and line. The species has a population restricted to a single river basin.
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 smallmouth silverside; in the meantime, see the similar species.
fun facts
- Its population is restricted to a single river basin in Mexico.
identification
Small, elongated, silvery fish, sardine-shaped with a small mouth, as its common name indicates. Atherinopsids have a silver stripe along the side of the body. In the same region, the Mezquital charal looks similar, and the safest sign is the place: this species is endemic to the Lerma River basin.
where found
Endemic to the Lerma River basin, in central Mexico, in fresh water.
Habitat: Fresh water, between midwater and the bottom, in the Lerma River basin.
rules for the smallmouth silverside
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.
Tiny, fragile fish: if it gets hooked, handle it as little as possible, with a wet hand, and return it quickly.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.00537, b = 3.09; FishBase (relação peso-comprimento bayesiana, estimativa)). 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: Chirostoma chapalae (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Chirostoma chapalaeNames 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: