''Pseudanos trimaculatus'', the threespot headstander, is a species of

headstander A headstander is any of several species of South American fish, including ''Anostomus ternetzi'', ''Anostomus anostomus'' (family Anostomidae) and members of genus ''Chilodus'' from the family Chilodontidae. The name derives from their habit of ...

found in

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Guyana Guyana ( or ), officially the Cooperative Republic of Guyana, is a country on the northern mainland of South America. Guyana is an indigenous word which means "Land of Many Waters". The capital city is Georgetown. Guyana is bordered by the ...

and

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

. ''Pseudanos trimaculatus'' exhibits a degree of geographical variation, with specimens found in the Amazon basin exhibiting much more conspicuous black spots at the center of their scales than their Essequibo or Orinoco basin counterparts

References

* *Birindelli, Britski, Flavio
''New species of Pseudanos Winterbottom, 1980 (Characiformes: Anostomidae), with notes on the taxonomy of P. gracilis and P. trimaculatus''
(2012). Anostomidae Freshwater fish of Argentina Freshwater fish of Brazil Fish of Guyana Freshwater fish of Peru Taxa named by Rudolf Kner Fish described in 1858 {{Characiformes-stub