Home / Fishes / Catfish / Megalancistrus parananus
No federal permit to keepMegalancistrus parananus
Megalancistrus parananus
Fishes › Catfish (Siluriformes) › Loricariidae (Plecos)
Megalancistrus parananus is a species of freshwater ray-finned fish belonging to the family Loricariidae, the suckermouth armoured catfishes, and the subfamily Hypostominae, the suckermouth catfishes.
Care at a glance
Species-specific aquarium care
- Tank: At least 90 in long and 45 in front to back for one adult (adults commonly reach about 23.1 in / 58.8 cm).
- Water: Freshwater.
- Layout: Lives on or near the bottom: floor space and hiding places matter more than height.
- Availability: Rarely or never seen in the aquarium trade; expect to source it from specialists or not at all.
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
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 68–82 °F, pH 6–7.5, 2–12 dGH.
- Behaviour: kept alone; not a community fish.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Diet: “Intestinal analyses of wild specimens have shown it to feed chiefly on freshwater sponges and other aquatic invertebrates alongside smaller quantities of wood, although it's unclear whether the latter is an essential part of the diet or ingested…”
- Tankmates: “Can behave very aggressively in confined surroundings and should only be maintained alongside similarly-sized, robust fishes in suitably-sized aquaria (see 'Aquarium Size').”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Plecos (suckermouth catfish)
Applies to most species in this group. Habitat: South American rivers. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Driftwood (some species rasp it for fiber), caves and good flow.
- Common plecos reach 18–24 in; many smaller species stay under 6 in.
Diet
- Algae wafers and vegetables for herbivores; meaty foods for carnivorous species.
Health watch
- Starvation if they're expected to live on algae alone.
Understanding the animal
About this animal
About this animal
This catfish is found in South America where it occurs in the drainages of the Paraguay, Paraná and Uruguay in Argentina, Brazil, Paraguay and Uruguay. This species reaches a standard length of 58.8 cm (23.1 in).
Quoted from the Wikipedia article “Megalancistrus parananus” (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. Stays near the bottom. |
| Water it lives in | Freshwater. |
| Climate | Temperate climate. |
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 87°F (up to 90°F in the hottest sampled areas) |
| Cool-season lows | about 53°F (down to 47°F in the coldest sampled areas) |
| Average temperature | 67–74°F across sampled records |
| Relative humidity | 72–75% on average (driest month about 65%) |
| Rainfall | about 1436 mm a year |
Measured at 62 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 | Megalancistrus parananus is a species of freshwater ray-finned fish belonging to the family Loricariidae, the suckermouth armoured catfishes, and the subfamily Hypostominae, the suckermouth catfishes. This catfish is found in South America where it occurs in the drainages of the Paraguay, Paraná and Uruguay in Argentina, Brazil, Paraguay and Uruguay. This species reaches a standard length of 58.8 cm. — 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 |
| Appearance and size | Maximum length 58.8 cm sl male/unsexed. — 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.
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; aim for the middle.
pH
Water hardness
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.
- Merck Veterinary Manual: Nutritional diseases of fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Seriously Fish — Ancistrus sp. “3” / common bristlenose identification Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
- 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.
More plecos
Ancistrus claro
Ancistrus claro
Aquarium hobby
Baryancistrus chrysolomus
Baryancistrus chrysolomus
Aquarium hobby
Baryancistrus demantoides
Baryancistrus demantoides
Aquarium hobby
Bushymouth catfish
Ancistrus dolichopterus
Aquarium hobby
Chaetostoma formosae
Chaetostoma formosae
Aquarium hobby
Chocolate-colored catfish
Rineloricaria lanceolata
Aquarium hobby