Black-winged Hatchetfish Care Guide
Carnegiella marthae · Freshwater Fish
What Black-winged Hatchetfish look like
The Black-winged Hatchetfish (Carnegiella marthae) exhibits a distinctive laterally compressed body shape, characterized by an extreme deep-keeled chest that contributes to its unique hatchet-like appearance. Adults typically reach a maximum size of approximately 1.5 inches (3.8 cm), with sexual dimorphism being subtle; males may display slightly more pronounced dark markings on the pectoral area. The body is primarily silver, adorned with a prominent dark triangular mark on the chest, referred to as the 'black wing,' which serves as a key identifying feature. The large, elongated pectoral fins facilitate surface gliding, while the presence of a small adipose fin and a well-defined lateral line enhances its hydrodynamic efficiency. Defensive adaptations include its ability to swiftly dart away from predators, utilizing its flattened body to blend into the water column's surface reflections.
Behavior & temperament
The Black-winged Hatchetfish is a social species that thrives in small groups, exhibiting a tendency to form loose schools within the upper water column, primarily in pelagic zones. These fish are known for their peaceful temperament, making them suitable for community tanks, although they can display slight territoriality during breeding periods. Breeding behavior involves egg scattering, where females release eggs into the water column, allowing fertilization to occur externally. This species is generally non-aggressive, preferring to avoid confrontation and instead utilizing their gliding ability to evade potential threats.
Diet & feeding
In the wild, the Black-winged Hatchetfish is an omnivore, feeding on small invertebrates, zooplankton, and plant matter. In captivity, they require a varied diet that includes high-quality flake food, frozen or live foods such as brine shrimp and daphnia, along with occasional vegetable matter to ensure optimal health.
Behind the name
Carnegiella (derived from 'Carnegie,' likely in honor of the philanthropist Andrew Carnegie); marthae (named in honor of a person, possibly Martha).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Black-winged Hatchetfish?
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