Acestrorhynchus lacustris, the Lake Pike Characin, is a medium-to-large predatory characin native to the Paraguay–Paraná drainage, one of the most species-rich river systems in South America. It has the characteristic long snout and sharp teeth of the genus, a silvery body with a prominent dark midlateral stripe running from the head to the caudal fin, and vivid fin markings. Growing to about 30 cm, it is one of the more accessible Acestrorhynchus species for specialist aquarists.
Care requires a minimum 600-litre aquarium with good oxygenation and strong filtration. As a subtropical species from the Paraná drainage it is somewhat more tolerant of cooler temperatures than its Amazonian relatives, with a lower temperature range of about 20°C acceptable. It is a fast, active predator that should never be kept with fish it can swallow.
Feeding includes live and frozen fish, prawns, and fresh fish strips, with gradual weaning toward high-quality carnivore pellets. Acestrorhynchus lacustris is one of the more feasible pike characins for the advanced hobbyist and makes a dramatic, active display fish in a specialist large South American predator setup.