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No federal permit to keepFlag cichlid
Mesonauta festivus
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Mesonauta festivus, the flag cichlid, is a species of cichlid native to the Paraná, Paraguay, Madre de Dios, Guaporé, Mamoré, Jamari and Tapajós river basins in Brazil, Peru, Paraguay and Bolivia.
Care at a glance
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 4.8 in / 12.1 cm).
- Water: Freshwater.
- Temperature: 77–93°F (range recorded for this species).
- pH: 6–8.
- Hardness: 4–6 dGH.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
- Diet: Eats a varied diet: mix quality prepared foods with frozen and live foods. FishBase classes it as a omnivore.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 47 × 15 in (roughly 36 US gallons); space needed is rated “large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, pH 6–8, 0–5 dGH.
- Difficulty: Not enough data to rate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Well planted tank with moderate water flow.”
- Diet: “It's a generalistic omnivore by nature.”
- Tankmates: “Peaceful cichlid, although becomes more aggressive when breeding.”
- Breeding: “Breeding takes place a flat stone or similar area.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Central and South American cichlids
Applies to most species in this group. Habitat: Rivers and lakes of the Americas. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Size ranges widely, from convicts at 5 in to Parachromis over 20 in; plan tank size for the adult fish.
- Most tolerate neutral, moderately hard water; strong filtration and rock or wood caves.
Climate & lighting
| Water | 75–82°F |
Diet
- Omnivorous cichlid pellets plus vegetables for herbivores (Vieja, Uaru) and meaty foods for predators (Parachromis).
Social life
- Territorial; breeding pairs can clear a whole tank.
Health watch
- Aggression and territorial injuries, especially when breeding; hole-in-the-head in poor water.
Understanding the animal
About this animal
About this animal
It can reach a standard length of 12.1 cm (4.8 in) and is sometimes kept in aquariums. It was generally recognized as the only valid species in the genus Mesonauta until 1991 when a taxonomic review found that five species should be recognized (a sixth was described in 1998).
Quoted from the Wikipedia article “Mesonauta festivus” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater, in rivers and streams. Uses both the bottom and open water. Reported to reach around 10 cm SL. |
| Water it lives in | Freshwater, 77–93 °F (25–34 °C), pH 6–8, hardness 4–6 dH. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: clutch tenders. |
What this means for care
- Keep water within its wild range, 77–93 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 91°F (up to 93°F in the hottest sampled areas) |
| Cool-season lows | about 70°F (down to 60°F in the coldest sampled areas) |
| Average temperature | 78–81°F across sampled records |
| Relative humidity | 76–83% on average (driest month about 75%) |
| Rainfall | about 2104 mm a year |
Measured at 343 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | Mesonauta festivus, the flag cichlid, is a species of cichlid native to the Paraná, Paraguay, Madre de Dios, Guaporé, Mamoré, Jamari and Tapajós river basins in Brazil, Peru, Paraguay and Bolivia. It can reach a standard length of 12.1 cm and is sometimes kept in aquariums. It was generally recognized as the only valid species in the genus Mesonauta until 1991 when a taxonomic review found that five species should be recognized (a sixth was described in 1998). — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Biology | Reported to reach around 10 cm SL. — FishBase |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Typical adult weight
Average adult body mass in each database (FishBase gives the maximum recorded weight).
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Minimum tank footprint
Seriously Fish recommends a tank base of at least 47 × 15 in (about 36 US gallons).
Veterinary & husbandry research
Veterinary & husbandry research
- Genomic and Environmental Factors Shape the Active Gill Bacterial Community of an Amazonian Teleost Holobiont Sylvain FÉ et al., Microbiology spectrum 2022
Peer-reviewed papers that mention this species alongside captivity, zoos, veterinary care or aquaculture. Some cover several species or mention it only in passing, so check the abstract. 170
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Merck Veterinary Manual: Management of aquarium fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Types and features of aquatic systems Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
- PubMed (U.S. National Library of Medicine) Peer-reviewed researchIndex of peer-reviewed veterinary, zoo and husbandry research.
- iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.
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