pacific deepwater flounder
Monolene maculipinna · Bothidae · predator
Deep-water flounder of the eastern Pacific, between 205 and 384 m. Anglers almost never encounter it, and the flesh is sold fresh.
Also called: linguado-do-Pacífico-profundo, lenguado de profundidad, lenguado, pacific deepwater flounder
- maximum
- 18 cm
- depth
- 205–384 m

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 pacific deepwater flounder
who is the pacific deepwater flounder
Flatfish of the family Bothidae, a deep-water species living on mud, sand and gravel bottoms between 205 and 384 m. It reaches 18 cm total length. It occurs in the eastern Pacific, from Costa Rica to Peru, and is also recorded in Nicaragua. Because it lives in deep bottoms, sport anglers almost never encounter it. The species is caught commercially, its flesh is sold fresh, and part of it is turned into fishmeal.
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 pacific deepwater flounder; in the meantime, see the similar species.
identification
Flattened, strongly compressed flatfish of the family Bothidae, with both eyes on the same side of the head. Depth, from 205 to 384 m, is the main trait to separate it from shallow flatfish of the same family, such as Bothus, which live between 1 and 150 m. The difference in depth is the main field clue.
where found
Occurs in the eastern Pacific, from Costa Rica to Peru, on mud, sand and gravel bottoms, between 205 and 384 m.
Habitat: Mud, sand and gravel bottoms, between 205 and 384 m deep.
rules for the pacific deepwater flounder
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.
It poses no danger to anglers. Because it lives in deep water, it may suffer barotrauma when brought up: release it carefully.
in the kitchen
The flesh is sold fresh, and part of the catch goes to fishmeal.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.00741, b = 3.06; 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: Monolene maculipinna (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Monolene maculipinnaNames 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: