The longtail sole[1] (Apionichthys dumerili) is a species of sole in the family Achiridae. It was described by Johann Jakob Kaup in 1858. It inhabits the Amazon, Corantijn, Grajaú, Orinoco, and Oyapock rivers. It dwells at a depth range of 1to.[2] It reaches a maximum total length of 15cm (06inches), more commonly reaching a TL of 11cm (04inches).
The longtail sole is currently ranked as Least Concern by the IUCN redlist, due to a lack of known major threats, although it notes that the species is harvested as bycatch in shrimp trawls at an undetermined rate.[2] The longtail sole is also marketed in the aquarium hobby.