Ninja Woodcat - (Centromochlus orca)

Fish Details, Description and Information Below:

🥷 Ninja Woodcat – (Centromochlus orca) – Black & White Brazilian Driftwood Catfish

The Ninja Woodcat (Centromochlus orca), also known as the Orca Woodcat or Ninja Tatia, is a small, unusual South American driftwood catfish recognized by its dramatic black-and-white coloration, enormous dark eyes, nocturnal behavior, and ability to disappear into tiny cracks and cavities during the day.

Its bold pattern is immediately recognizable:

Deep black upper body
Bright white underside
Irregular white patches extending upward along the sides
Large dark eyes
Pale fins with contrasting dark markings
Black-and-white pattern reminiscent of an orca

That resemblance inspired the scientific species name:

orca

Although called a “woodcat,” this species should not be thought of as a pleco-like wood grazer or a bottom-cleaning catfish.

Wild Centromochlus orca have actually been observed actively swimming through the midwater and near the surface at night, where they search for small animal foods.

🔎 Quick Facts – Ninja Woodcat

📛 Common Name: Ninja Woodcat
📛 Other Names: Orca Woodcat, Ninja Tatia, Orca Driftwood Catfish
🔬 Scientific Name: Centromochlus orca
📚 Older Scientific Combination: Tatia orca
📅 Formally Described: 2017
🐟 Family: Auchenipteridae
🧬 Subfamily: Centromochlinae
🌎 Origin: South America
🇧🇷 Country: Brazil
🌊 Primary Native Drainage: Rio Nhamundá Basin
📍 Type Locality: Mouth of Igarapé Jamari with Lago de Terra Santa, Pará, Brazil
📍 Additional Locality: Lagoa Sete Ilhas near the Amazonas–Pará border
💧 Water Type: Freshwater
🏞️ Natural Habitat: Floodplain-edge channels, lake margins and slow or nearly still water
🌙 Activity: Strongly nocturnal / crepuscular
🏊 Nighttime Position: Midwater and surface activity documented
📏 Scientific Maximum: 5.68 cm / approximately 2.2 inches standard length
📏 Adult Planning Size: Approximately 2.25–2.5 inches
🏠 Recommended Aquarium: 20 gallons or larger
👥 Small Group: Approximately 20–30+ gallons with abundant shelters
🌡️ Temperature: Approximately 75–82°F
💧 pH: Approximately 6.0–7.5
💦 Water: Soft to moderately mineralized
💨 Oxygenation: Good
🌊 Water Movement: Gentle to Moderate
🚫 Strong Current Required: No
🍽️ Diet: Small Animal / Invertebrate-Based Omnivore
🦐 Frozen & Live Foods: Very Important
🐛 Insect Foods: Excellent
🚫 Algae Cleaner: No
🚫 Detritus Cleaner: No
🪵 Driftwood: Strongly recommended for shelter
😌 Temperament: Peaceful
⚠️ Tankmate Size: Keep with peaceful fish too small to intimidate or outcompete it
🥚 Reproduction: Internal fertilization occurs within this catfish group
🔬 Male Feature: Modified anal fin associated with insemination
⭐ Care Level: Intermediate
🌎 IUCN Status: Least Concern

🧬 Current Scientific Name

The currently accepted scientific name is:

Centromochlus orca

The species was formally named by:

Sarmento-Soares, Lazzarotto, Rapp Py-Daniel & Leitão

and is currently recognized as a valid member of the family:

AUCHENIPTERIDAE

or:

DRIFTWOOD CATFISHES

📚 What About Tatia orca?

Aquarium literature may also list this fish as:

Tatia orca

That name reflects a previous taxonomic placement.

Modern classification has returned the species to:

Centromochlus

Therefore, the correct current product name is:

**Ninja Woodcat – (Centromochlus orca)**

Older references using Tatia orca can still contain useful husbandry information, but the scientific name on the product page should be updated to Centromochlus orca.

🐋 Why Is It Called orca?

The species name:

orca

refers directly to its remarkable resemblance in coloration to the:

ORCA / KILLER WHALE

The fish has a sharply contrasting:

Black upper body
White underside
Irregular white side markings

creating an unmistakable black-and-white pattern.

🥷 Why “Ninja Woodcat”?

The aquarium name:

NINJA WOODCAT

fits its behavior extremely well.

During daylight, this fish can seemingly:

DISAPPEAR

into:

Driftwood cracks
Hollow branches
Narrow caves
Rock crevices
Tubes
Shaded structures

It may remain almost completely invisible until the aquarium lights dim.

👀 Huge Eyes

One of the most noticeable characteristics of Centromochlus orca is its:

VERY LARGE EYES

The original scientific description specifically noted the unusually large eye diameter as an identifying characteristic.

Those large eyes fit perfectly with its:

NOCTURNAL LIFESTYLE

and allow it to function effectively in low-light environments.

🎨 Appearance

The upper body is generally:

Black
Charcoal
Very dark brown-black

while the underside is:

BRIGHT WHITE

The boundary between the black and white areas is not straight.

Instead, it forms an attractive:

WAVY, IRREGULAR BORDER

along the fish's sides.

⚪ White Side Markings

The white coloration extends upward onto portions of the lower sides of the body.

This creates:

White patches
Irregular bands
Broken markings
High-contrast shapes

against the black background.

Individual fish can show slightly different patterns.

⚠️ Pattern Variation

Exact black-and-white markings cannot be guaranteed.

Individuals may differ naturally in:

Amount of white
Shape of side patches
Tail pattern
Fin coloration
Width of black areas

Stress can also temporarily alter overall coloration.

🆚 Ninja Woodcat vs. Centromochlus musaicus

A particularly important identification issue involves:

Centromochlus musaicus

which has historically been confused with C. orca.

The two species are:

NOT THE SAME FISH

🐟 Centromochlus orca

The Ninja / Orca Woodcat is associated primarily with:

THE RIO NHAMUNDÁ BASIN IN BRAZIL

and has a black body with:

LARGE, CLEAR WHITE AREAS

extending upward onto the lower sides.

🐟 Centromochlus musaicus

Centromochlus musaicus originates from the:

UPPER ORINOCO SYSTEM

and differs in:

Geographic origin
Pattern arrangement
Pigmentation
Certain anatomical characteristics

Because aquarium trade names have historically been confused, scientific identification is important.

⚠️ Preserve Scientific Identification

For this product, use:

Centromochlus orca

rather than assuming every black-and-white “Ninja Tatia” is the same species.

Supplier and collection information should be preserved whenever available.

🌎 Native Distribution

Centromochlus orca is native to:

BRAZIL

and was originally scientifically described from the:

RIO NHAMUNDÁ BASIN

along the border region between:

Pará
Amazonas

📍 Type Locality

The type locality is:

MOUTH OF IGARAPÉ JAMARI WITH LAGO DE TERRA SANTA

near:

TERRA SANTA, PARÁ, BRAZIL

within the:

RIO NHAMUNDÁ BASIN

🌊 Lagoa Sete Ilhas

Additional original specimens were collected from:

LAGOA SETE ILHAS

upstream from Nhamundá near the boundary between:

Amazonas
Pará

This region represents an ecological transition between:

THE AMAZON FLOODPLAIN

and:

THE GUIANA SHIELD

🌊 Important Habitat Correction

It would be easy to assume that a small Amazonian catfish requires:

STRONG RIVER CURRENT

but that is not what scientists observed for Centromochlus orca.

At Igarapé Jamari:

THE WATER CURRENT WAS VIRTUALLY ABSENT

Wild fish were found around the transition between:

Flowing channels
Quiet floodplain habitats
Várzea lakes

Therefore:

DO NOT BUILD THE CARE GUIDE AROUND STRONG CURRENT

🌊 Aquarium Water Movement

A much better aquarium recommendation is:

GENTLE TO MODERATE WATER MOVEMENT

with:

Good filtration
Good surface oxygen exchange
Quiet sheltered areas
No extreme torrent conditions

Strong current throughout the aquarium may make it more difficult for these small nocturnal fish to feed comfortably.

🌙 Wild Fish Are Active at Night

Every specimen in the original field study was collected:

AT NIGHT

This confirms the strongly nocturnal nature of the species.

💡 Wild Fish Were Attracted to Lighted Areas

One of the most interesting observations was that Ninja Woodcats were seen actively swimming near:

Shoreline lights
Boat lights

at night.

They were observed in:

THE MIDWATER

and:

NEAR THE WATER SURFACE

🏊 Not Just a Bottom-Dwelling Catfish

This is an important correction.

Although Centromochlus orca spends daylight hours hiding around structure:

IT IS NOT STRICTLY A BOTTOM FISH

At night, it can actively enter:

Midwater
Upper water levels
Surface-feeding zones

in search of food.

🍽️ Feed the Entire Water Column

Because of this behavior, do not offer only:

HEAVY SINKING BOTTOM TABLETS

Instead, provide a mixture of foods that:

Sink slowly
Drift through the water
Remain suspended temporarily
Reach sheltered nighttime feeding areas

This better matches natural feeding behavior.

📏 Adult Size

FishBase documents a maximum of:

5.68 CM STANDARD LENGTH

or approximately:

2.2 INCHES BEFORE THE FULL TAIL

Other aquarium references commonly place total adult size around:

2.25–2.5 INCHES

Therefore:

EXPECT APPROXIMATELY 2.25–2.5 INCHES AS AN ADULT

🐱 True Dwarf Catfish

Unlike many aquarium catfish that are sold small but eventually become enormous:

THIS REALLY IS A SMALL SPECIES

That makes it an excellent option for aquarists wanting an unusual catfish without needing a giant aquarium.

🏠 Aquarium Size

For a single fish or small compatible group:

20 GALLONS OR LARGER

is a good starting point.

20–30+ GALLON

aquarium provides considerably more room for:

Multiple shelters
Nighttime swimming
Feeding areas
Small peaceful tankmates

📐 Horizontal Space

Although tiny, the Ninja Woodcat becomes an active swimmer after dark.

Prioritize:

HORIZONTAL SWIMMING AREA

rather than a very tall aquarium.

🪵 Aquarium Setup

A suitable aquarium should contain:

Driftwood
Branches
Hollow wood
Small caves
Narrow tubes
Rock crevices
Leaf litter when appropriate
Shaded areas
Plants
Floating plants
Open nighttime swimming areas

🪵 Driftwood Is Important for Shelter

As a driftwood catfish, this species strongly appreciates:

TIGHT WOODEN HIDING PLACES

Useful structures include:

Hollow driftwood
Root tangles
Branch intersections
Narrow wood crevices

🚫 Driftwood Is Not Food

Unlike:

Panaque
Panaqolus

the Ninja Woodcat does:

NOT EAT WOOD AS A SPECIALIZED DIET

Driftwood is primarily:

Shelter
Security
Shade
Territory
Environmental structure

🏠 Tight Shelters Are Especially Important

These fish often prefer spaces that appear:

ALMOST TOO SMALL

for them.

Suitable shelters include:

Narrow tubes
Small hollow wood sections
Tight rock cracks
Tiny caves

They may wedge themselves deeply into a shelter during daylight.

⚠️ Check Décor Before Moving It

Because Ninja Woodcats hide extremely deeply inside wood:

NEVER ASSUME A PIECE OF DRIFTWOOD IS EMPTY

before removing it from an aquarium.

A fish may be hidden completely inside.

Always inspect submerged décor carefully before:

Removing wood
Moving the aquarium
Cleaning shelters
Transferring fish

🌿 Planted Aquariums

Ninja Woodcats are excellent candidates for planted aquariums.

They generally do not damage:

Plants
Roots
Leaves

A heavily planted aquarium can help them feel secure.

🌿 Floating Plants

Floating plants can provide:

Dim lighting
Security
Shade
Natural cover

and may encourage the fish to become more active earlier in the evening.

🌡️ Temperature

A practical long-term range is:

75–82°F / 24–28°C

Stable temperature is more important than chasing one exact number.

💧 Water Parameters

A practical aquarium range is:

🌡️ Temperature: Approximately 75–82°F
💧 pH: Approximately 6.0–7.5
💦 Hardness: Soft to moderately mineralized
💨 Oxygenation: Good
🌊 Water Movement: Gentle to Moderate
☠️ Ammonia: 0 ppm
☠️ Nitrite: 0 ppm
🔄 Nitrate: Keep low

💨 Oxygenation

Provide reliable:

GOOD OXYGENATION

through:

Surface agitation
Proper filtration
Air stones when useful

However, this should not be confused with creating:

EXTREME CURRENT

The species' natural habitat includes very slow water.

💩 Filtration

Because these are small fish, their individual bioload is modest.

However, they still require:

Mature biological filtration
Stable water quality
Regular maintenance

Suitable filtration can include:

Sponge filters
Hang-on-back filters
Canister filters
Small sump systems

⚠️ Protect Filter Intakes

These fish are:

Small
Nocturnal
Curious
Able to enter narrow spaces

Use an:

INTAKE PREFILTER / SPONGE

where necessary to prevent fish from entering filter plumbing.

🍽️ Diet – Small Animal / Invertebrate Foods

The Ninja Woodcat should be fed primarily as a:

SMALL NOCTURNAL PREDATOR / OMNIVORE

rather than an algae-eating catfish.

🐛 Excellent Foods

Suitable foods include:

Bloodworms
Mosquito larvae
Daphnia
Cyclops
Small insect larvae
Small insect-based foods

🦐 Small Crustacean Foods

Excellent choices include:

Baby brine shrimp
Adult brine shrimp
Mysis chopped appropriately
Small crustacean-based frozen foods

🥣 Prepared Foods

Once acclimated, many specimens will accept:

Small sinking micro-pellets
Soft granules
Small carnivore pellets
Insect-based micro-pellets
Fine omnivore foods

🌙 Feed After Lights Dim

Because the species is strongly nocturnal:

EVENING FEEDING IS VERY IMPORTANT

Offer at least part of its food:

At dusk
Immediately after lights out
Under dim lighting

⚠️ Make Sure the Ninja Woodcat Actually Eats

One of the greatest husbandry mistakes is assuming that a nocturnal catfish will survive on:

LEFTOVERS

It may not.

🚫 Not a Cleanup Fish

Do not purchase a Ninja Woodcat as a:

Bottom cleaner
Algae eater
Waste eater
Leftover-food scavenger

It requires:

ITS OWN DELIBERATE FEEDING

just like every other aquarium fish.

⚠️ Food Competition Can Be Dangerous

Because Ninja Woodcats are:

Small
Shy
Nocturnal

they can lose food to:

Fast tetras
Barbs
Large cichlids
Aggressive catfish
Large plecos

A fish can slowly starve even while the aquarium appears to be receiving plenty of food.

🍽️ Feeding Strategy

A good strategy is to:

Feed other fish normally
Wait until lighting dims
Add a second small feeding for the woodcats
Deliver food near their shelters
Include slowly sinking foods

👀 Monitor Body Condition

Healthy fish should maintain:

Full body profile
Normal activity
Good muscle condition

Watch for:

Sunken belly
Hollow flanks
Weak swimming
Long-term hiding combined with weight loss

🌙 Daytime Behavior

During daylight, the Ninja Woodcat may:

REMAIN COMPLETELY HIDDEN

This is normal.

It does not automatically indicate:

Illness
Stress
Poor health

if the fish becomes active and feeds normally after dark.

🌙 Nighttime Behavior

After dark, the fish may transform into an active swimmer.

It may:

Leave wood cavities
Patrol the aquarium
Swim through midwater
Feed near the surface
Search actively for small prey

This is one of the most interesting aspects of keeping the species.

😌 Temperament

The Ninja Woodcat is generally:

PEACEFUL

and poses little threat to appropriately sized tankmates.

🐟 Tankmates

Good companions can include peaceful fish such as appropriately selected:

Small tetras
Pencilfish
Rasboras
Corydoras
Small peaceful cichlids
Other non-aggressive community fish

provided water requirements are compatible.

⚠️ Avoid Very Large or Aggressive Fish

Because the Ninja Woodcat reaches only about:

2.5 INCHES

avoid housing it with fish capable of:

Swallowing it
Bullying it
Controlling all food
Constantly forcing it from shelter

👥 Keeping More Than One

Ninja Woodcats can be maintained in:

SMALL GROUPS

when enough hiding places are available.

Provide:

MULTIPLE SHELTERS

rather than forcing several fish into one small cavity.

🪵 Shelter Competition

Even peaceful woodcats may compete for preferred:

Hollow wood
Tubes
Cracks

Provide several options of different:

Diameters
Shapes
Locations

♂️ Male vs. Female

Auchenipterid driftwood catfish have unusual reproductive anatomy.

Mature males develop a modified:

ANAL FIN

associated with:

INTERNAL INSEMINATION

🔬 Scientific Observation in C. orca

The original species description examined sexual development in Centromochlus orca.

Researchers observed a maturing male with a:

PARTIALLY MODIFIED ANAL FIN

consistent with the reproductive specialization characteristic of this group.

🥚 Unusual Reproduction

Driftwood catfish are unusual among catfish because fertilization occurs:

INTERNALLY

rather than through the simple external fertilization familiar from many aquarium catfish.

The female can receive sperm from the male before eggs are deposited.

⚠️ Not a Typical Cave-Spawning Pleco

Do not describe Centromochlus orca as reproducing like:

Ancistrus
Hypancistrus
Peckoltia

This is:

NOT A MALE-GUARDED PLECO CAVE-SPAWNING SYSTEM

It belongs to an entirely different catfish family with a different reproductive strategy.

🥚 Captive Breeding Information

Species-specific captive breeding information for:

Centromochlus orca

remains limited and somewhat inconsistent in aquarium literature.

Some aquarium sources report successful reproduction of Orca/Ninja woodcats, while others still describe commercial specimens as primarily wild collected.

Because of this:

DO NOT PRESENT EXACT BREEDING INSTRUCTIONS AS ESTABLISHED FACT FOR C. ORCA

⚠️ Avoid Inventing Exact Egg Numbers

Until better species-specific documentation is available, I would avoid claiming exact:

Clutch size
Incubation period
Spawning cave size
Fry count
Breeding trigger

for Centromochlus orca.

🧬 Family-Level Reproductive Strategy

What is well supported is that Centromochlinae have:

Modified male anal fins
Internal insemination
Egg-laying reproduction

This is already much more unusual than the reproductive biology of most commonly kept aquarium catfish.

🌎 Conservation Status

Centromochlus orca is currently assessed as:

LEAST CONCERN

on the IUCN Red List.

The global assessment dates to:

2020

🌿 Why Least Concern?

The species has been reported as:

Locally abundant
Present at multiple locations
Not primarily targeted by commercial fisheries

Although specimens are collected for the ornamental aquarium trade, the original scientific researchers did not consider that collection to represent a major threat to the wild population.

⚠️ Least Concern Still Requires Responsible Care

Least Concern does not mean aquarium fish are disposable.

Every specimen should still receive:

Proper acclimation
Appropriate food
Correct tankmates
Permanent suitable housing

⭐ Why Keep a Ninja Woodcat?

The Ninja Woodcat combines:

🥷 Extremely secretive daytime behavior
🐋 Beautiful orca-like black-and-white coloration
👀 Enormous nocturnal eyes
🌙 Fascinating nighttime activity
🏊 Midwater and surface feeding behavior
🪵 Driftwood-cavity lifestyle
📏 True dwarf adult size of approximately 2.5 inches
😌 Peaceful temperament
🧬 Unusual internal fertilization biology
🇧🇷 Brazilian Amazon origin

into one of the most unusual small catfish available to freshwater aquarists.

⚠️ Important Considerations

Before purchasing a Ninja Woodcat:

The correct current scientific name is Centromochlus orca.
Tatia orca is an older taxonomic combination.
Do not confuse C. orca with Centromochlus musaicus.
The species originates from Brazil.
Its primary native distribution is the Rio Nhamundá Basin.
The type locality is Igarapé Jamari at Lago de Terra Santa in Pará.
Wild fish occur near the transition between the Amazon floodplain and Guiana Shield.
Natural habitat can have extremely little current.
Do not describe this as a strong-current river catfish.
Provide gentle to moderate water movement.
Maintain good oxygenation and clean water.
Wild fish are strongly nocturnal.
At night they have been observed swimming through midwater and near the surface.
Do not treat the species as strictly bottom-dwelling.
Feed small frozen, live, and prepared animal-based foods.
Offer some food after the aquarium lights dim.
Do not expect the fish to survive on leftovers.
Do not purchase it as an algae cleaner.
Do not purchase it as a detritus cleaner.
Driftwood is important primarily for shelter.
This species does not eat wood like Panaque or Panaqolus.
Scientific maximum is approximately 5.68 cm standard length.
Plan for approximately 2.25–2.5 inches total adult size.
A 20-gallon or larger aquarium works well.
Provide numerous tight hiding places.
Use peaceful tankmates that will not outcompete it for food.
Keep filter intakes protected.
Male reproductive anatomy is modified for internal insemination.
Do not describe reproduction as typical pleco cave spawning.
Exact species-specific captive breeding information remains limited.
The species is currently Least Concern.
Never release aquarium fish into natural waterways.

🧬 Taxonomy

The currently accepted scientific name is:

Centromochlus orca Sarmento-Soares, Lazzarotto, Rapp Py-Daniel & Leitão, 2017

Classification:

Order: Siluriformes
Family: Auchenipteridae
Subfamily: Centromochlinae
Genus: Centromochlus
Species: orca

Older combination:

Tatia orca

Native distribution:

RIO NHAMUNDÁ BASIN – BRAZIL

For this product, use:

**Ninja Woodcat – (Centromochlus orca)**

🐋 Identification Disclaimer

Black-and-white driftwood catfish have historically been confused in the aquarium trade.

The Ninja / Orca Woodcat Centromochlus orca should not automatically be confused with:

Centromochlus musaicus

Useful identification information includes:

Black-and-white pattern
Amount of white extending onto the sides
Geographic origin
Supplier identification
Collection locality when available

🚚 Live Fish Shipping

Live fish are professionally packed for safe transport.

Shipping availability depends on:

Fish size
Destination
Weather conditions
Carrier availability
Applicable state and local regulations

Because Ninja Woodcats are small and secretive, appropriate packing should provide secure transportation while minimizing unnecessary stress.

Please review our Shipping & Payment Information and Live Arrival Guarantee / DOA Policy before ordering.

⚠️ Buyer Responsibility

Customers are responsible for confirming that Centromochlus orca may legally be purchased, possessed, transported, and received in their state or local jurisdiction before ordering.

Never release aquarium fish into natural waterways.