Piabucus dentatus

Piabucus dentatus, also called the chin tetra or the coastal piabucus, is a species of freshwater ray-finned fish belonging to the family Iguanodectidae. This species is found in coastal rivers of northern South America. Preferred habitats are generally high in silt content and are slow-moving, including floodplain streams and estuaries.

It is one of the earliest known South American fish in Northern ichthyology, believed to have been recorded first in 1648. It did not have a standard scientific name until 1766, though it had an earlier description in 1763 without a binomial moniker. German botanist Joseph Gottlieb Kölreuter was responsible for the 1763 description, while Swedish taxonomist Carl Linnaeus prescribed its first true scientific name - Salmo argentinus - in 1766.