Pterophyllum is a small genus of freshwater fish from the family Cichlidae known to most aquarists as "Angelfish". All three Pterophyllum species (Altum, Leopoldi, and Scalare) originate from the Amazon River basin in tropical South America. Angelfish are unusually shaped for cichlids being greatly laterally compressed, with round bodies and elongated triangular dorsal and anal fins. They are normally found in swamps or flooded grounds where vegetation is dense and the water is either clear or silty. Depending on the species, most Angelfish are frequently found in the well oxygenated, extremely soft waters, with a pH range between 4.5 to 6.8. Temperature range in their natural habit is between 24°C - 30°C. Angelfish are ambush predators and prey on small fish and macroinvertebrates. All Pterophyllum species form monogamous pairs. Eggs are generally laid on a submerged log or a flattened leaf. As is the case for other cichlids, brood care is highly developed.