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No federal permit to keep

Keyhole cichlid

Cleithracara maronii

Also known as Keyhole

Fishes › Cichlids (Cichliformes) › Cichlidae (Cichlids)

The keyhole cichlid (Cleithracara maronii) is a cichlid fish endemic to tropical South America, occurring in the lower Orinoco Basin in Venezuela and river basins in The Guianas.

Aquarium hobby

Experience: Intermediate

Keyhole cichlid — Photo: Bartosz Senderek, CC BY-SA 2.5, via Wikimedia Commons

Photo: Bartosz Senderek, CC BY-SA 2.5, via Wikimedia Commons

FamilyCichlids

Adult lengthup to 4.3 in

WaterFreshwater, brackish

HabitatLives in freshwater and brackish water

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 2.8 in / 7.1 cm).
Water: Freshwater (tolerates brackish).
Temperature: 72–77°F (range recorded for this species).
pH: 6–8.
Hardness: 0–20 dGH.
Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
Diet: A predator: feed meaty foods sized to its mouth (frozen fish, shrimp, worms); it will eat tankmates that fit in its mouth. FishBase classes it as a carnivore.

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 35 × 12 in (roughly 21 US gallons); space needed is rated “large tank”.
Water: a fairly wide range, from slightly acidic to slightly alkaline, 70–82 °F, pH 4–7.5, 2–15 dGH.
Behaviour: in a pair; suited to a community tank.
Difficulty: Moderate (Seriously Fish rating).

Short excerpts from the species profile:

Setup: “Provided adequate cover and structure is available this species is unfussy with regards to décor with ceramic flowerpots, lengths of plastic piping and other artificial materials all useful additions.”
Diet: “Likely to be a foraging omnivore feeding on benthic invertebrates and organic detritus in nature.”
Tankmates: “Not aggressive unless breeding and will not predate on fishes larger than a few mm in length.”
Breeding: “This species is a biparental, monogamous substrate spawner and is easily-bred when in good condition.”

From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167

Group care guide

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.

Sources 117 119 164

Climate & lighting

Water

75–82°F

Sources 117 119 164

Diet

Omnivorous cichlid pellets plus vegetables for herbivores (Vieja, Uaru) and meaty foods for predators (Parachromis).

Sources 117 119 164

Social life

Territorial; breeding pairs can clear a whole tank.

Sources 117 119 164

Health watch

Aggression and territorial injuries, especially when breeding; hole-in-the-head in poor water.

Sources 117 119 164

Understanding the animal

About this animal

It is the only species in the genus Cleithracara. The species is popular with fishkeeping hobbyists and is frequently kept in aquariums.

Quoted from the Wikipedia article “Keyhole cichlid” (CC BY-SA 4.0) 174

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 and brackish water, in rivers and streams. Uses both the bottom and open water. Inhabits small creeks in the coastal zone, which have clear water and little current.
Water it lives in	Freshwater / brackish water, 72–77 °F (22–25 °C), pH 6–8, hardness 20 dH.
Climate	Tropical climate.
Wild diet	Hunting macrofauna (predator).
Behavior to plan for	Breeding: clutch tenders.

What this means for care

Keep water within its wild range, 72–77 °F.
It tolerates or needs brackish water; check salinity needs before setup.

FishBase species summary: Cleithracara maronii

Native climate (measured)

Warm-season highs	about 89°F (up to 91°F in the hottest sampled areas)
Cool-season lows	about 70°F (down to 69°F in the coldest sampled areas)
Average temperature	78–80°F across sampled records
Relative humidity	80–85% on average (driest month about 79%)
Rainfall	about 2552 mm a year

Measured at 41 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

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	The keyhole cichlid (Cleithracara maronii) is a cichlid fish endemic to tropical South America, occurring in the lower Orinoco Basin in Venezuela and river basins in The Guianas. It is the only species in the genus Cleithracara. The species is popular with fishkeeping hobbyists and is frequently kept in aquariums. — 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
Wild diet	The species feeds on crustaceans, insects and other invertebrates. — Wikipedia (community-edited)
Reproduction	Spawns on hard substrate; produces up to 600 eggs; both parents guard eggs and larvae. — FishBase
Appearance and size	The species is a small tan coloured ovate-bodied fish. It has a black spot on its upper flank which sometimes extends into a short stripe. This gives rise to the common name, keyhole cichlid, from which the genus name Cleithracara (meaning "lock acara") is derived. — Wikipedia (community-edited)
Biology	Inhabits small creeks in the coastal zone, which have clear water and little current and is rich in decaying wood. Feeds on worms, crustaceans and insects. When faced with danger, this fearful species fix itself against a log adapting its color pattern to the substrate. — FishBase

Data and studies

The numbers

Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.

Adult length

Average of sources3.5in

FishBase 1642.8

Seriously Fish species profiles 1674.3

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

Average of sources71–79.5°F

FishBase 16472–77

Seriously Fish species profiles 16770–82

Range the species tolerates in nature; aim for the middle.

pH

Average of sources5–7.8

FishBase 1646–8

Seriously Fish species profiles 1674–7.5

Water hardness

Reported2–15dGH

Seriously Fish species profiles 1672–15

Minimum tank footprint

Reported35in

Seriously Fish species profiles 16735

Seriously Fish recommends a tank base of at least 35 × 12 in (about 21 US gallons).

Federal legal snapshot

No federal permit to keep

No federal law singles out this species for private keepers. State and local rules still apply.

State law decides most of it. Each state sets its own permits and bans for exotic, native, venomous and dangerous animals, and cities and counties can be stricter. Find your state agency →

Not covered by the Animal Welfare Act

The Act only covers warm-blooded animals. Reptiles, amphibians, fish and invertebrates have no federal care standards, even at licensed facilities; state and local rules may still apply.

Kept in captivity?

Every species on this site needs evidence that people actually keep it. For this one:

Has a Seriously Fish aquarium species profile
FishBase records it in the aquarium trade (Aquarium=highly commercial; AquariumFishII=based mainly on breeding; aquarium reproduction record)
2 iNaturalist observations of captive animals

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.
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.