''Acestrorhynchus altus'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

in the family

Acestrorhynchidae ''Acestrorhynchus'' ("needle jaw" ) is a genus of 14 species of characiform fish found only in fresh water in South America, the sole genus in the family Acestrorhynchidae. Their greatest diversity is in the Orinoco and Amazon basins. These fish ...

. It was described by Naércio Aquino de Menezes in 1969. It inhabits the

Amazon River The Amazon River (, ; es, Río Amazonas, pt, Rio Amazonas) in South America is the largest river by discharge volume of water in the world, and the disputed longest river system in the world in comparison to the Nile. The headwaters of t ...

basin, at a pH range of 5.5-7.2. It reaches a maximum

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

of . ''A. altus'' feeds off of

bony fish Osteichthyes (), popularly referred to as the bony fish, is a diverse superclass of fish that have skeletons primarily composed of bone tissue. They can be contrasted with the Chondrichthyes, which have skeletons primarily composed of cartilag ...

.Food items reported for ''Acestrorhynchus altus''
at www.fishbase.org.

References

Acestrorhynchidae Taxa named by Naércio Aquino de Menezes Fish described in 1969 {{Characiformes-stub