Members of the parrot genus Psittacula or Afro-Asian ring-necked parrots, as they are commonly known in aviculture, originate from Africa to South-East Asia. It is a widespread group with a clear concentration of species in south Asia, but also with representatives in Africa and the islands of the Indian Ocean. This is the only genus of parrot which has the majority of its species in continental Asia. Of all the extant species only Psittacula calthropae, Psittacula caniceps and Psittacula echo do not have a representative subspecies in any part of mainland continental Asia. The rose-ringed parakeet, Psittacula krameri, is one of the most widely distributed of all parrots.
The other two Asian genera, Loriculus and Psittinus are represented by only two species each, which occur in the mainland part of Asia. The majority of the Loriculus species occur on islands. Moreover, since Loriculus is spread across both sides of the Wallace Line it can be considered more Australasian than Asian. These parrots mostly have green plumage, with adults having coloured heads. The bill is stout, and the tail is long and graduated.
Etymology
The genus name Psittacula is a diminutive of the Latin word psittacus meaning "parrot".
Taxonomy
The genus Psittacula was introduced in 1800 by the French naturalist Georges Cuvier. The type species was designated in 1923 by Gregory Mathews as the red-breasted parakeet. The name of the genus is a diminutive of the Latin word psittacus for a "parrot".
The genus includes 16 species, of which three are extinct.
†Newton's parakeet, Psittacula exsul - extinct (c.1875) Echo parakeet, Psittacula eques †Réunion parrot, Psittacula eques eques - extinct mid-18th century †Mascarene grey parakeet, Psittacula bensoni - extinct (c.1764) (formerly classified in genus †Lophopsittacus, and still considered such by some authorities) Rose-ringed parakeet, Psittacula krameri Alexandrine parakeet, Psittacula eupatria †Seychelles parakeet, Psittacula wardi - extinct (1883) Plum-headed parakeet, Psittacula cyanocephala Blossom-headed parakeet, Psittacula roseata Slaty-headed parakeet, Psittacula himalayana Grey-headed parakeet, Psittacula finschii Blue-winged parakeet, Psittacula columboides Layard's parakeet, Psittacula calthrapae Lord Derby's parakeet, Psittacula derbiana Red-breasted parakeet, Psittacula alexandri (also called moustached parrot) Long-tailed parakeet, Psittacula longicauda Nicobar parakeet, Psittacula caniceps
Alternative taxonomy
Genetic evidence has found that the genus Psittacula is likely paraphyletic; for example, genetic analysis has supported merging short-tailed parrots of the genus Tanygnathus, Psittinus, and the extinct Mascarinus with Psittacula. A revised classification was proposed by Michael Braun and coworkers in 2019 that splits the genus Psittacula into multiple monophyletic genera in order to preserve Tanygnathus, Psittinus, and Mascarinus as distinct genera. After the proposed split, the only remaining species in Psittacula sensu stricto are P. derbiana, P. caniceps, and P. alexandri. This is also the taxonomic system followed by the IUCN Red List and BirdLife International. The list of split or monophyletic genera and species (and any of their allied species) is displayed below: