Black Wolf Fish (Hoplias curupira)

Scientific Name: Hoplias curupira

Common Name: Black Wolf Fish, Curupira Wolf Fish

Family: Erythrinidae

Order: Characiformes

Native Habitat: The Black Wolf Fish (Hoplias curupira) is native to the freshwater rivers, streams, and lakes of South America, specifically found in the Amazon and Orinoco river basins. It thrives in warm, slow-moving waters with dense vegetation, submerged rocks, and logs. This species prefers slightly acidic to neutral waters with temperatures ranging between 75°F and 82°F (24°C to 28°C), and a pH of 6.0 to 7.5.

Physical Characteristics

Size: The Black Wolf Fish can grow up to 18-24 inches (46-61 cm) in length, with males generally being slightly smaller than females. They are robust, muscular fish with a powerful frame that enables them to be dominant hunters in their habitat.

Appearance: The Black Wolf Fish has a sleek, elongated body that tapers toward the tail. Its body coloration is generally dark, ranging from a deep brown to black, often with subtle lighter highlights or markings along the body. They have a distinct, large head with powerful jaws that are filled with sharp, canine-like teeth, which they use to catch and hold onto prey. Their small, rough scales and streamlined body design make them highly efficient predators.

Fins and Tail: The Black Wolf Fish has a large, muscular dorsal fin running along its back. The tail fin is broad and forked, providing powerful propulsion for quick bursts of speed. Its pectoral fins are set high on the body, aiding in its agility and maneuverability in the wild. These fins help it navigate in the dense, obstacle-filled environments where it resides.

Behavior and Ecology

Feeding Habits: The Black Wolf Fish is a carnivorous species and is known for its aggressive hunting behavior. It primarily preys on smaller fish, invertebrates, and occasionally frogs. Using its sharp teeth and strong jaws, it can grasp and tear apart its prey. In captivity, it requires a high-protein diet, such as live or frozen fish, shrimp, and other meaty foods. While they are opportunistic predators, Black Wolf Fish can also exhibit cannibalistic tendencies if food is scarce or if housed with smaller fish.

Social Behavior: The Black Wolf Fish is a solitary species and is known for its territorial nature. They are often aggressive toward other fish, especially those that are smaller or less robust. While they can be kept with other large, similarly sized or aggressive fish, they should not be housed with small or peaceful species, as the Black Wolf Fish may see them as prey. Their territorial behavior can also extend to their own species, so care should be taken when keeping multiple individuals.

Reproduction: In the wild, the Black Wolf Fish spawns during the rainy season, when water levels rise, and food becomes abundant. The male and female work together to guard the nest where they lay their eggs. These fish are not known for extensive parental care but may guard the eggs for a short time after spawning. Breeding in captivity is rare but possible with proper water conditions and an appropriately sized tank. A breeding pair requires a stable environment with clean, well-filtered water and plenty of space to reduce stress and aggression.

Care and Maintenance in Captivity

Aquarium Setup: A minimum tank size of 75 gallons (284 liters) is recommended for a single Black Wolf Fish, with larger tanks required if multiple fish are being kept together. The tank should have plenty of hiding spots, such as rocks, caves, or driftwood, to help reduce stress and provide a sense of security. A strong filtration system is crucial to keep the water clean, as these fish are known to produce a significant amount of waste. The Black Wolf Fish prefers a tank with subdued lighting and a natural, soft substrate to mimic its native environment.

Water Conditions:

• Temperature: 75°F to 82°F (24°C to 28°C)
• pH: 6.0 to 7.5 (slightly acidic to neutral)
• Hardness: Soft to moderately hard water (6-12 dGH)
• Filtration: A powerful filtration system is essential to maintain clean water and avoid high levels of ammonia or nitrites. These fish require excellent water quality to thrive, and frequent water changes are recommended.

Tankmates: The Black Wolf Fish is best kept with other large, aggressive fish that can defend themselves. Suitable tankmates include large cichlids, catfish, and other robust species. Small or peaceful fish should be avoided, as they may become prey for the Black Wolf Fish. If keeping multiple Black Wolf Fish, ensure there is sufficient space to reduce territorial aggression.

Diet in Captivity: The Black Wolf Fish requires a high-protein diet, including live or frozen fish, shrimp, and other meaty foods. They may also accept high-quality carnivore pellets, though live foods are often preferred for maintaining natural hunting instincts. It is important to vary their diet to ensure they receive all necessary nutrients. Overfeeding should be avoided to maintain water quality, as Black Wolf Fish are often messy eaters.

Unique Traits

Aggressive Predator: The Black Wolf Fish is a powerful, aggressive predator, known for its canine-like teeth and strong jaws. These traits make it an excellent hunter in the wild, and a striking presence in the aquarium. Its territorial nature can make it a challenge for aquarium keepers, but its unique appearance and dynamic behavior make it a fascinating addition to large, species-specific tanks.

Distinctive Appearance: The Black Wolf Fish has a sleek, muscular build with dark brown to black coloration and sharp, angular teeth. Its impressive size and appearance make it a standout species in the aquarium trade. Its large head and powerful body provide an intimidating look, adding to its "wolf-like" reputation.

Conservation Status

IUCN Status: The Black Wolf Fish (Hoplias curupira) is not currently listed as endangered, but it is threatened by habitat destruction, pollution, and overfishing in parts of its range. As with many species from the Amazon River Basin, deforestation and water pollution are significant threats to their populations. Conservation efforts to protect the habitats of these fish are essential for their continued survival.

In Summary

The Black Wolf Fish (Hoplias curupira) is a striking and powerful species, known for its aggressive predatory behavior and sharp, canine-like teeth. As a carnivorous species, it requires a high-protein diet and a spacious, well-maintained aquarium with proper filtration and water conditions. While it can be challenging to keep due to its territorial nature, the Black Wolf Fish can be a rewarding and dynamic addition to an aquarium for experienced fishkeepers. With proper care, it can thrive and grow into a stunning, impressive centerpiece for a large tank.