Author: (Linnaeus, 1758)
FBname: Drab sole
Remark: The species <i>Achirus lineatus</i> Quoy & Gaimard, 1824 is cited as valid by Dennis <i>et al.</i> (2004: Ref. 51183) from Puerto Rico, followed by Eschmeyer (CofF ver. July 2013: Ref. 93826).  However, a complete revision of the genus is necessary to sort out the difficulties.  The distribution of <i>A. achirus</i> is referrred by Chabanaud (1928: 23) as "West coast of Americas, including West Indies. Cited from 7°N  from 34°S.", and Cervigon (1966: 812) as "north and east of Gulf of Mexico to Rio Grande do Sul state, Brazil" (data on both papers are coincident). Cervigón (1996: 16) states: "its distribution extends from Golfo de Paria to Amazonas". No papers dealing with Achiridae include reference to a punctual collection of <i>A. achirus</i> in Gulf of Mexico or West Indies; Meek and Hildebrand (1928) do not cite this species to Panama. <i>A. achirus</i> was described from Suriname, and there are records from Venezuela, Suriname (the original description and other papers which refer to it), and Brazil (Figueirerdo & Menezes, 2000, Rosa, 1980). <i> A. achirus</i> securely do not occurs in southeastern South America (Figueirerdo & Menezes, 2000), the most south collection was taken at Paraíba state, northeastern Brazil (Rosa, 1980). The probable distribution of <i>A. achirus</i> is the coastal areas from Venezuela to northeastern Brazil, but it's necessary further studies to make a secure statement on distribution of this species. As several achirid species, it is a marine species which occasionally enters freshwaters; there is at least on record of this species for freshwater (Tocantins River at Cametá, Pará state, Brazil). Ortega and Vari (1986) cite <i>A. achirus</i> for freshwaters of Peru (Amazon basin), but it is a misidentification, as this species do not occurs in highland freshwaters. In this area occurs <i>Hipoclinemus mentalis</i>, which is frequently confounded with <i>A. achirus</i>.
Comments: Adults occur in the littoral zone, down to 20 m depth, and on all sandy-muddy bottoms of estuaries, rivers and coastal streams where it penetrates far enough sometimes.  They hide completely in the sediment, leaving out its eyes, in order to look out for predators and prey.  Feed on small crustaceans and fish.  Reproduction is like to occur between July and September (Ref. 35237).  Maximum length reported to reach 37 cm TL (Ref. 5217).