Psittacidae
The Order Psittaciformes comprises about 350 species distributed in 84 genera (Collar 1997, Rowley 1997 apud Tavares et al.), and almost 27% of them are endangered to varying degrees (BirdLife International 2000). They are distributed throughout the southern portion of North America, Central and South America, the Caribbean Islands, Africa, Indian and Pacific islands, the Australasian region, and southern Asia.(Tavares, Yamashita and Miyaki 2004).
Amazon parrots (Genus Amazona) are among the most recognizable and coveted of all birds. Their colorful plumage and general ability to mimic speech has endeared them to humans as pets for centuries and, as an unfortunate consequence, contributed to the imperiled status of the majority of Amazon species in the wild.
According to the 2002 IUCN Red List of Threatened Animals, 18-31 species of Amazonsare listed as either vulnerable, endangered or in the case of the Puerto Rican Amazon (Amazona vittata), critically endangered (IUCN, 2002). Similarly, all Amazona species are listed under the Convention on International Trade in Endangered Species (CITES) Appendix I (15 species) or Appendix II (16 species). Despite this notoriety, however, little is known about the evolutionary history of the group, including only a limited understanding of the phylogenetic relationships among the large number of Amazona species.
Amazon parrots are phenotypically characterized by their medium to large size, strong-heavy bill, shortrounded tail, prominent naked cere and the presence of a distinct notch in the upper mandible (Forshaw, 1989). As with most members of Psittacidae, sexual dimorphism in Amazons is slight or absent. Body plumage is generally green varying from darker shades to yellowgreen across species, although the plumage of a number of Antillean island endemics are an exception to this general pattern. Variable colorations on the head, breast, wing coverts, and/or flight feathers that span all spectrums of the rainbow have been used to characterize different species.
According to general estimates, Amazonaincludes 27-31 species widely distributed in Central and South America (Mexico to Argentina), and throughout the Caribbean. The number of recognized species varies based on different treatments of Yellow-headed parrots as a single (Amazona ochrocephala) or three separate species (A. ochrocephala, Amazona auropalliata, Amazona oratrix); the distinction of the Red-browed Amazon (Amazona rhodocorytha) as a separate species from the Blue-cheeked Amazon (Amazona dufresniana) or as a subspecies of the latter; and in the recognition of the extremely rare, and only recently described White-faced Amazon (Amazona kawalli; Grantsau and de Almeida Camargo, 1990; Martuscelli and Yamashita, 1997 apud Russelo et al). The number of species may further increase upon more thorough investigation of the plethora of subspecies described in such widespread groups as Amazona autumnalis, Amazona amazonica, Amazona aestiva, and Amazona farinosa.
(Russelo e Amato 2004).
References
Russelo, Michael A., Amato, George. 2004. A molecular phylogeny of Amazona: implications for Neotropical parrot biogeography, taxonomy, and conservation. MOLECULAR PHYLOGENETICS AND EVOLUTION. 2004, Vol. 30, pp. 421-437.
Tavares, Erika S., Yamashita, Carlos., Miyaki, Cristina Y. 2004. PHYLOGENETIC RELATIONSHIPS AMONG SOME NEOTROPICAL PARROT GENERA (PSITTACIDAE) BASED ON MITOCHONDRIAL SEQUENCES. The Auk. 2004, Vol. 121, 1, pp. 230-242.
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