CW049 Black Diamond Cory Catfish – Hoplisoma sp. CW049

The CW049 Black Diamond Cory Catfish (Hoplisoma sp. CW049) is one of the most visually distinctive black-and-white Cory-type catfish available to specialty freshwater aquarists.

Also known as the Black Diamond Cory, Diamond Cory, CW049 Cory, or New Panda CW049, this fish combines a light-colored body with sharply defined black markings that create a dramatic high-contrast appearance.

The signature marking is a large black diamond or wedge-shaped patch extending downward from the dorsal-fin region. A separate dark band passes through the eye, giving the fish a masked appearance.

CW049 first became widely known in the aquarium hobby after exports from Colombia began around 2010. It entered the hobby at approximately the same time as the very similar CW051, leading to early uncertainty over whether the two represented different species or simply different patterns.

Taxonomy note: CW049 has not yet received a formal scientific species description. Historically it was called Corydoras sp. CW049. Following the 2024 revision of Corydoradinae, this short-snouted lineage is now placed in the resurrected genus Hoplisoma, making Hoplisoma sp. CW049 the appropriate modern designation.

CW049 Black Diamond Cory Catfish Care Information

What Does a CW049 Black Diamond Cory Look Like?

The CW049 Black Diamond Cory has a compact, short-snouted Hoplisoma body with a pale cream, ivory, light tan, flesh-toned, or pale golden body.

A bold black vertical band passes through the eye, covering much of the height of the head and creating a strongly masked appearance.

The most recognizable feature is the large black diamond-shaped marking centered around the dorsal-fin region. The dark patch extends from the dorsal fin downward into the side of the body and narrows toward its lower point.

The sharp contrast between the pale body and solid black markings gives CW049 its characteristic Black Diamond appearance.

Why Is CW049 Called the Black Diamond Cory?

The name Black Diamond Cory refers to the large, sharply defined black marking below and around the dorsal fin.

In well-marked specimens, this central patch forms a diamond, wedge, or inverted triangular shape against the pale background of the body.

This black diamond is the defining visual feature of CW049 and one of the easiest ways to distinguish it from the related-looking CW051.

CW049 Black Diamond Cory vs. CW051 New Panda Cory

CW049 and CW051 are closely similar black-and-white Hoplisoma forms that entered the aquarium hobby from Colombia around the same period.

Early imports created uncertainty over whether the two represented separate species or merely different color patterns of a single species.

Captive breeding has since provided an important clue: both forms have bred true to their characteristic patterns. This strongly supports the interpretation that they represent distinct taxa rather than simple individual color variation.

The easiest visible difference is the central body marking. In CW049, the black saddle is approximately as wide as the base of the dorsal fin and usually narrows into a diamond or wedge shape down the side.

In CW051, the dark saddle is substantially broader and extends farther toward the adipose-fin region.

CW049 Black Diamond Cory vs. Panda Cory

CW049 can loosely resemble the familiar Panda Cory (Hoplisoma panda) because both have pale bodies and strong black markings.

However, the classic Panda Cory has three relatively separate markings: a dark eye mask, a dark dorsal marking, and a separate dark patch around the caudal peduncle.

CW049 instead has a much more dramatic black diamond-shaped central body marking extending downward from the dorsal-fin region.

They are separate fish from different geographic regions and should not be treated as color morphs of one another.

Is There a Long-Snouted Form of CW049?

Specialist aquarium records report a rare longer-snouted fish with a CW049-like pattern.

Current observations suggest that the longer-snouted form may belong to a different evolutionary lineage, potentially closer to the modern genus Brochis.

This long-snouted form has not received its own CW number and appears to be much less commonly encountered in the aquarium trade.

The standard CW049 offered under the Black Diamond Cory name is the round- or short-snouted Hoplisoma form.

What Does CW049 Mean?

CW049, also written CW49, is the Corydoras World identification number assigned to this undescribed Cory-type catfish.

CW numbers provide aquarists, importers, breeders, and researchers with a standardized way to identify distinctive Corydoradinae populations before formal scientific descriptions are available.

Keeping the CW049 designation is especially important because this fish can easily be confused with CW051 and other black-and-white Hoplisoma species.

Why Is CW049 Now Hoplisoma sp. CW049?

CW049 was historically known as Corydoras sp. CW049.

Modern phylogenetic research demonstrated that the traditional broad genus Corydoras contained several separate evolutionary lineages.

In the major 2024 Corydoradinae revision, the large short-snouted Lineage 9 group was placed in the resurrected genus Hoplisoma.

Corydoras World now lists CW049 within this genus, so the appropriate current hobby name is Hoplisoma sp. CW049.

Where Do CW049 Black Diamond Corys Come From?

CW049 originates from the Colombia–Brazil border region of northwestern South America.

Specialist locality information places the fish in a small creek flowing toward the Rio Içá, near the indigenous settlement of Boa Vista.

The Rio Içá is the Brazilian continuation of the Putumayo River system, part of the greater Amazon drainage.

Aquarium exports of CW049 have commonly moved through Leticia, Colombia, one of the most important ornamental fish export centers in this border region.

Is the CW049 Black Diamond Cory Rare?

CW049 remains a specialty collector Cory in the aquarium trade. It is much less widely available than common species such as Panda, Bronze, Sterbai, or Peppered Corys.

Both wild-collected and captive-bred CW049 have appeared in the trade, and successful breeding may gradually improve availability.

The term “rare” here refers to aquarium-trade availability and should not be interpreted as an official conservation-status classification.

CW049 Black Diamond Cory Behavior & Group Size

Black Diamond Corys are peaceful, social bottom-dwelling fish and should not be kept individually.

Keep at least 6 CW049 Corys together. Groups of 8 or more are even better when aquarium size and availability allow.

A proper social group usually encourages more confident movement, group foraging, and visible activity around the aquarium.

Like other Corydoradinae catfish, CW049 may occasionally make a rapid trip to the surface to gulp atmospheric air before returning to the substrate. Occasional surface visits are normal behavior.

Ideal Aquarium Setup for CW049 Black Diamond Cory

A 20–30 gallon or larger freshwater aquarium provides a practical starting point for a proper group of Black Diamond Corys.

Horizontal bottom space is more important than excessive aquarium height. A longer aquarium allows the group to move and forage comfortably.

A fine sand substrate is strongly recommended. CW049 uses sensitive barbels around the mouth while searching through the substrate for food.

Driftwood, roots, smooth stones, dried leaves, live plants, floating plants, and shaded areas can provide security while open sandy sections allow natural foraging.

Because CW049 is often associated with soft, acidic forest-stream habitats, botanical materials such as dried leaves can work particularly well in a natural-style aquarium, although a full blackwater setup is not mandatory for healthy captive maintenance.

CW049 Black Diamond Cory Water Parameters

A practical aquarium temperature range for CW049 is approximately 73–79°F (23–26°C).

A pH of approximately 5.5–7.2 is suitable, with soft to moderately soft water preferred.

Stable water quality is more important than constantly adjusting the aquarium to reach one exact number.

Keep CW049 in a mature, fully cycled aquarium with good biological filtration, strong oxygenation, and regular partial water changes.

Ammonia and nitrite should remain at zero. This is especially important for wild-origin or recently imported Black Diamond Corys.

What Do CW049 Black Diamond Cory Catfish Eat?

CW049 Black Diamond Corys are omnivorous benthic foragers and should receive a varied diet provided specifically for them.

Good aquarium foods include:

• High-quality sinking Cory pellets
• Bottom-feeder tablets or granules
• Bloodworms
• Blackworms
• Brine shrimp
• Daphnia
• Tubifex
• Other appropriately sized frozen or live foods

Wild-origin specimens may initially respond especially well to frozen or live foods before becoming accustomed to prepared aquarium diets.

CW049 Black Diamond Cory Tank Mates

The peaceful temperament of Hoplisoma sp. CW049 makes it suitable for carefully planned freshwater community aquariums.

Potential tank mates include peaceful tetras, pencilfish, rasboras, small danios, peaceful dwarf cichlids, small gouramis, and other non-aggressive freshwater species with compatible water requirements.

Other Cory-type catfish can also be compatible, but keeping another species in the same aquarium does not replace the social requirement for a proper group of CW049 itself.

Avoid large predatory fish, highly territorial bottom dwellers, and aggressive or excessively competitive species.

Male vs. Female CW049 Black Diamond Cory

Juvenile CW049 can be difficult to sex reliably. Differences become clearer as fish reach maturity.

Adult males generally remain slimmer and more streamlined.

Adult females typically become larger and noticeably broader through the abdomen, particularly when viewed from above.

Color and black-diamond pattern alone should not be used to determine sex, because both males and females display the characteristic CW049 markings.

Why Choose CW049 Black Diamond Cory Catfish?

• Distinctive black diamond-shaped body marking
• Bold black eye mask on a pale body
• High-contrast collector appearance
• Historic CW049 / CW49 identification
• Still-undescribed specialty Hoplisoma species
• Peaceful social temperament
• Interesting Colombia–Brazil border locality
• Captive breeding has been successfully established
• Excellent choice for serious Cory and Hoplisoma enthusiasts

CW049 Black Diamond Cory Catfish FAQ

What is a CW049 Black Diamond Cory Catfish?

CW049 is an undescribed Cory-type catfish from the Colombia–Brazil border region. It has a pale body, black eye mask, and a distinctive diamond-shaped black marking extending downward from the dorsal-fin area. Its modern designation is Hoplisoma sp. CW049.

Is CW049 now Hoplisoma sp. CW049?

Yes. It was historically listed as Corydoras sp. CW049. Following the 2024 revision of Corydoradinae, its short-snouted lineage is placed within Hoplisoma, making Hoplisoma sp. CW049 the appropriate modern designation.

What does CW049 mean?

CW049 is the Corydoras World identification number assigned to this scientifically undescribed fish. It allows aquarists and breeders to identify the population consistently until a formal species name is published.

Why is CW049 called the Black Diamond Cory?

The common name refers to the sharply defined black diamond or wedge-shaped marking that extends downward from the dorsal-fin region against the fish's pale body.

What is the difference between CW049 and CW051?

CW049 generally has a narrower diamond- or wedge-shaped central black marking approximately as wide as the dorsal-fin base. CW051 has a much broader saddle-shaped black patch extending farther toward the adipose-fin area.

Are CW049 and CW051 different species?

Neither has yet received a formal scientific species description. However, both forms have been bred in captivity and have maintained their respective patterns, which strongly supports treating them as distinct taxa rather than simple color variations.

Is CW049 the same as a regular Panda Cory?

No. The regular Panda Cory is Hoplisoma panda and comes from a different part of South America. CW049 has a large diamond-shaped central black marking that is not present on a standard Panda Cory.

Is there a long-snouted CW049?

A rare longer-snouted fish with a similar pattern has been reported in the aquarium trade. Specialists suspect that this form may belong to a different lineage, possibly closer to Brochis. The standard CW049 Black Diamond Cory is the short-snouted Hoplisoma form.

How big do CW049 Black Diamond Corys get?

Most aquarium references place adults around 2–2.5 inches, with mature females generally becoming larger and broader-bodied than males.

How many CW049 Black Diamond Corys should be kept together?

Keep at least 6 CW049 Corys together. Groups of 8 or more are even better when aquarium space and availability allow.

What temperature is best for CW049 Black Diamond Corys?

A practical aquarium range is approximately 73–79°F (23–26°C), with a pH around 5.5–7.2.

Where do CW049 Black Diamond Corys come from?

Specialist locality information places CW049 in the Colombia–Brazil border region, in a small tributary associated with the Rio Içá / Putumayo system near Boa Vista. Many aquarium exports pass through Leticia, Colombia.

Is the CW049 Black Diamond Cory rare?

CW049 is considerably less common in the aquarium trade than mainstream Cory species and is generally considered a specialty collector fish. This describes aquarium availability rather than an official conservation-status category.

Are CW049 Black Diamond Cory Catfish peaceful?

Yes. CW049 is a peaceful social catfish that works well with calm freshwater community fish such as tetras, pencilfish, rasboras, and other non-aggressive species with compatible care requirements.

What do CW049 Black Diamond Cory Catfish eat?

Feed a varied diet containing quality sinking pellets, tablets, or granules supplemented with frozen or live foods such as bloodworms, blackworms, brine shrimp, daphnia, and Tubifex.

Do CW049 Black Diamond Corys clean the aquarium?

CW049 naturally forage along the aquarium floor, but they should not be treated as aquarium maintenance animals. They require intentional feeding with nutritious foods along with regular water changes, substrate cleaning, and normal aquarium maintenance.