Serrasalmus maculatus · Mac

Overview

Serrasalmus maculatus is a comparatively manageable-sized piranha requiring dedicated accommodation. Predation on small fishes and biting at other fishes' fins make solitary maintenance the default; isolated reports of coexistence do not establish general compatibility.

Distribution & habitat

Originally described from the Guaporé in western Brazil, it is recorded across the Amazon, Paraguay, and Paraná systems in Colombia, Peru, Brazil, Bolivia, Paraguay, Uruguay, and Argentina.

Rivers, pools, and creeks are occupied, apparently with a preference for shaded vegetation-rich margins. Wild groups of roughly twenty have been observed patrolling an area, which does not establish safety in a confined aquarium.

Aquarium setup

A single adult needs about 120 × 45 cm of floor space or more. Sand and woody shelter suit a well-oxygenated layout. Plants can be tried but may be bitten.

Maintain excellent water quality with substantial weekly partial changes, up to roughly 50%. Keep heating outside the display where possible, or use robust guards around vulnerable submerged equipment.

Diet & feeding

Natural feeding includes fins and flesh, small fish, insects, and crustaceans; small quantities of plant material have also appeared in stomach analyses. Newly imported fish may initially reject dead food, so monitor intake and condition during adjustment.

Young fish take bloodworms, Tubifex, Artemia, and chopped shrimp. Adults need larger suitable items, including shellfish, squid, small fish, and earthworms, generally two or three feedings weekly. Avoid substantial mammalian or bird meat and unnecessary feeder fish, which can carry parasites or disease.

Behaviour & compatibility

Keeping one specimen is the prudent standard. Reports of successful combinations with catfish or conspecifics remain uncertain. Group maintenance is disputed and requires extensive experience and much greater accommodation than the single-fish recommendation.

Sexual dimorphism

No dependable routine external distinction is recorded. Females approaching spawning are usually rounder in the abdomen.

Breeding

Captive reproduction is documented, and wild spawning is not strictly seasonal. Attempts demand several large aquaria and capacity for numerous fry.

One detailed account began with adults in a planted aquarium exceeding 750 L. Identified partners were conditioned separately for about two weeks. A male then entered a further planted tank, followed by the female roughly a day later. Male aggression sometimes caused serious injury, and waiting times varied, making separation facilities essential.

The male selected a site and clipped vegetation without consuming it. Repeated contact over that site produced approximately eight hundred to twelve hundred eggs. At 28 °C, hatching took about fifty-four to fifty-eight hours, with free swimming within a week. Young received suitably small live foods, including Artemia nauplii. Adults were removed in that attempt, while other observations describe aggressive paternal guarding of the eggs.

Notes

Confusion with Serrasalmus spilopleura has been longstanding. A dark band near the tail's outer portion and cheek structure offer identification clues, but aspects of the taxonomic treatment remain debated. Golden-mac trade names are not definitive identification.