Serrasalmus geryi

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Serrasalmus geryi, also called the Violet-Line Piranha, is a South American piranha prized for its dark coloration and distinctive violet stripe. This rare species comes from the Rio Araguaia in Brazil, where it inhabits freshwater sections of large tropical rivers. Its compressed body, sharp teeth, and predatory behavior make it a fish for experienced aquarists. The specimens offered by Ton.Fish are wild collected, and this species is available exclusively from Ton.Fish in Canada. Since it is considered very rare in the aquarium trade, its care requires a spacious, stable, and carefully planned setup.

General species description

Serrasalmus geryi is a solitary piranha in the genus Serrasalmus, adapted to an opportunistic predatory lifestyle in the Rio Araguaia basin. It differs from more common red-bellied piranhas through its slimmer profile, overall silver to dark-gray coloration, and distinctive longitudinal violet line on the flanks. Its behavior is often cautious, but it remains a powerful predator with teeth capable of causing serious injuries. In aquaria, it should be kept alone or in a setup specifically designed for solitary piranhas. This very rare species is offered by Ton.Fish in Canada as a wild-collected fish, making acclimation and quarantine especially important.

Geographic origin and biotope

Serrasalmus geryi originates from Brazil, within the Rio Araguaia basin. It is associated with freshwater sections of this major river system, where conditions vary with the season, water level, and shoreline structure. The regional biotope includes areas with moderate to strong current, bottoms made of sand, gravel, and stones, and shelter formed by submerged branches and riparian vegetation. Water may be relatively clear in some areas. In an aquarium, provide an open, well-oxygenated environment structured with a few sturdy roots while preserving plenty of swimming space. Efficient filtration and stable water conditions are essential for a wild-caught fish.

Precise location and local name

The origin generally associated with Serrasalmus geryi is the Rio Araguaia in Brazil. Its range is therefore connected to a particular river system rather than to the entire Amazon basin. The international trade name is Violet-Line Piranha, referring to the violet stripe visible along the flanks. In Brazil, the name piranha-roxa may be used in reference to its purplish coloration. This species remains extremely uncommon in specialty stores; its arrival at Ton.Fish in Canada is an exceptional opportunity for aquarists interested in collector piranhas. The fish offered are wild collected and must be handled with care because of their dentition.

Appearance and physical characteristics

Serrasalmus geryi has the deep, laterally compressed body typical of Serrasalmus, along with a strong head, powerful jaws, and very sharp triangular teeth. Adult coloration ranges from silver-gray to brownish gray and is often highlighted by a violet flank stripe. The fins may show reddish or orange tones, especially when the fish is mature and well acclimated. The adipose fin and overall body shape help with identification, although coloration can change with mood, lighting, and water quality. An adult maximum of approximately 25 cm is generally used for aquarium planning. As in several solitary piranhas, sexual differences are subtle and usually do not allow reliable visual sexing.

General diet

In the wild, Serrasalmus geryi is an opportunistic predator that consumes fish, pieces of flesh, and various available aquatic organisms. In aquaria, offer a varied diet based on aquarium-safe feeder fish, shrimp, and suitable mollusks in controlled portions. Live food is not essential and may introduce parasites; quality frozen foods are generally safer. Avoid mammal and bird meat, which is too rich in lipids and unsuitable for its physiology. Meals should remain moderate to limit waste and digestive problems. Very clean water, strong oxygenation, and close observation of appetite are essential, especially after the arrival of a wild-caught fish.

Essential data

• Native river: Rio Araguaia
• Local name: piranha-roxa
• Origin of the scientific name: Serrasalmus identifies the genus; geryi honors ichthyologist Jacques Géry.
• Etymology of the full name: serra means saw, salmus refers to salmon, and geryi means of Géry.
• Common/vernacular names: Violet-Line Piranha; piranha-roxa
• Family: Serrasalmidae
• Subfamily: Serrasalminae
• Name pronunciation: ser-ra-SAL-mus JER-ee-eye
• Discovery: described by Jégu and Santos in 1988
• Maximum adult size: approximately 25 cm
• Water temperature and pH: 24 to 28 °C; approximately pH 6.0 to 7.5
• Waterway appearance and surrounding vegetation: sometimes clear freshwater, wooded banks, and riparian vegetation associated with the cerrado
• Typical tankmates: medium and large fish from the Rio Araguaia basin; aquarium cohabitation is not recommended
• Temperament and behavior: predatory, cautious, generally solitary, and territorial
• Water depth: variable according to location and season
• Sexual dimorphism: very subtle; the sexes are difficult to distinguish visually
• Bottom structure and flow: sand, gravel, stones, and woody debris; variable, often moderate to strong current
• Availability: very rare, wild collected, and available exclusively from Ton.Fish in Canada

In your aquarium

Success with Serrasalmus geryi depends on a very spacious, secure aquarium reserved for a single specimen. Provide a tight-fitting lid, oversized filtration, excellent oxygenation, and regular water changes. Roots and shaded areas can help reduce stress, but a large open swimming area should remain available. Careful quarantine is important for a wild-collected fish, especially after long transport. Feed moderately and never handle the fish directly. This very rare species, available exclusively from Ton.Fish in Canada, is best suited to an experienced aquarist able to provide stable long-term conditions.