Thayeria boehlkei, the blackline penguinfish, is a species of freshwater ray-finned fish belonging to the family Acestrorhamphidae, the American characins. This species is endemic to the Amazon River basin and Araguaia River, in Peru and Brazil respectively. The species is popular with aquarium hobbyists, and is traded under a variety of common names including blackline penguinfish, blackline thayeria, hockey-stick tetra, penguin fish and penguin tetra.Mills D (1993) Aquarium Fish Harper Collins Axelrod HR, Vorderwinkler W (1995) Encyclopedia of tropical fishes. 30th edition. Tropical Fish Hobbyist Publications, USA.
The fish is named in honor of James E. Böhlke (1930–1982) of the Academy of Natural Sciences of Philadelphia, because of his interest in and contributions to the knowledge of South American characids.
Distribution and habitat Thayeria boehlkei inhabits small streams and the margins of smaller rivers in the lowland Amazon basin, where it has been recorded in the Araguaia, Tocantins, Xingu, Tapajós and Teles-Pires rivers.
Diet The species feeds on worms, small insects, flake food and crustaceans.
Reproduction In captivity, this normally schooling species forms pairs that scatter their many adhesive eggs amongst plants. Clutch size is very large and may be up to 1000 eggs, the embryos of which are black in colour.McInerny D, Gerard G (1958) All about tropical fish. 2nd Edn. George Harrap & Co. London. p. 276–277. The eggs hatch in about 20 hours and are free-swimming after four days.
In the aquarium The species is best kept in groups, to allow the species to school, in tropical freshwater community aquaria with other peaceful, non-predatory fishes. This fish tolerates a fairly broad range of water pHs, but prefers acidic water for breeding.
See also Tetra List of freshwater aquarium fish species
References
External links Penguin Tetra Fact Sheet Badmans Tropical Fish Mongabay