The green kingfisher (Chloroceryle americana) is a species of "water kingfisher" in subfamily Cerylinae of family Alcedinidae. It is found from southern Texas in the United States south through Central America, in every mainland South American country except Chile, and on Trinidad and Tobago. Taxonomy and systematics The green kingfisher was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with the other kingfishers in the genus Alcedo and coined the binomial name Alcedo americana. Gmelin based his description on "Le martin-pêcheur vert et blanc" from Cayenne that had been described and illustrated in 1780 by the French polymath Comte de Buffon and also the "white and green kingfisher" that had been described in 1782 by the English ornithologist John Latham. The green kingfisher is now placed in the genus Chloroceryle that was introduced in 1848 by Johann Jakob Kaup. A molecular phylogenetic study published in 2006 found that the green kingfisher is a sister species to the larger green-and-rufous kingfisher (C. inda). Five subspecies are recognized: C. a. hachisukai (Laubmann, 1941) C. a. septentrionalis (Sharpe, 1892) C. a. americana (Gmelin, JF, 1788) C. a. mathewsii Laubmann, 1927 C. a. cabanisii (Tschudi, 1846) Some populations of C. a. septentrionalis have in the past been separated as subspecies C. a. vanrossemi and C. a. isthmica. The population on Trinidad and Tobago, usually included with C. a. americana, has in the past been treated as subspecies C. a. croteta. Other populations of C. a. americana have been suggested to be split as C. a. hellmayri and C. a. bottomeana. None of these subspecies are currently (2022) recognized by major worldwide taxonomic systems. Description The green kingfisher is about long and weighs about ; females are larger and heavier than males. Birds in the northern and southern parts of its range, and those west of the Andes, are larger and heavier than the others, but the differences tend to be clinal. The species has the typical kingfisher shape with long heavy bill (heaviest in Trinidad and Tobago); in contrast to many other kingfishers, however, it does not have an obvious crest. The bill is black with some horn color at the base of the mandible and its legs and feet are dark gray. Both sexes have green upperparts with two or more rows of white spots on