In l828, the genus Encyclia has been described by Hooker who published in Botanical Magazine but only in 1914, the revaluation of it has been proposed by Schlecther.
In l838, the genus Prosthechea has been proposed and described by Knowles & Westc. However it was not used until l997 when it has been reestablished by W.E. Higgins.

All the controversy raised around those genera makes us to return at the begging of the orchids classification, with Linnaeus when he established, in 1753, the genus Epidendrum (which means living on the trees) sheltering a great number of plants which were, morphologically, really different. Thus, he, as many others who became after him, put a great number of orchids inside this genus. During the centuries, with the improvement of the studies, new genera have been created and the species have been transferred to do part of genera more adequate to their characteristics. For example, it happened to Cattleya amethystoglossa initially described as Epidendrum amethystoglossum, with Cattleya dolosa, Cattleya aurantiaca and so on.
Many genera had already have their species as belonging to the genus Epidendrum and many species of Stelis, Vanilla, Oncidium, Schomburgkia, Cochleanthes, Coryanthes, Cyrtopodium, Sophronitis, Lockhartia, Bletia, had already belonging to this genus.

With all those modifications, little by little, only the species really close remained inside the genus Epidendrum, the most distant migrated to a more adequate genus. Therefore, many species that have been, lately, transferred to the genus Encyclia (and, some, subsequently to Prosthechea) stayed there for long time, which disagreed many botanists and orchidologists. Although they recognized the proximity of the species, they saw differences enough to do new modifications and went on their search of new ways to do a more adequate classification. New genera were proposed but many of them did not remain as we can verify in the summary bellow:

In l828, Encyclia Hooker but it remained not accepted until revaluated later by Schlecther.

In l838, Prosthechea Knowles & Westc. but not accepted.

In 1841, Heynold adapted a name proposed by Lindley (from Epidendrum subg. Hormidium Lindl.), Hormidium and inside it put just one only species [Hormidium uniflorum (Lindl.) Heynh, nowadays Prosthechea pygmaea (Hook.) W.E. Higgins]. After that and, until l982, some species have been successively included in this genus but they remained known as Epidendrum or Encyclia.

In l842, the genus Anacheilium has been proposed by Reichenbach (ex Hoffmanns) but it stayed as synonym.

In 1914, Schlechter proposed the revaluation of the genus Encyclia Hook "...transferring to it plants with an entirely or partially free, generally tri-lobed labellum adhering to the column and little developed clinandrum..."(Guido J. F. Pabst, José Luiz de Araujo Moutinho& Antonio Ventura Pinto, em Reestablishing of the genus Anacheilium Hoffmgg and revision of the genus Hormidium Lindl. ex Heynh.).

In 1939, Acuña try to revalidate the genus Anacheilium Rchb. (ex Hoffmanns) and transferred Epidendrum fragrans Sw. to this genus as Anacheilium fragrans (Sw.) Acuña. Once again, this nomenclature is not adopted.

In l952, Hoehne transferred Epidendrum tripartitum Vell. as Encyclia tripartita (Vell.) Hoehne.

In l955, Lemée transferred Epidredrum fragrans Sw. as Encyclia fragrans (Sw) Lemée.

In l961, Dressler transferred species to the genus Encyclia, such as, for example, Epidendrum pygmaeum Hook which became Encyclia pygmaea (Hook.) Dressler [nowadays Prosthechea pygmaea (Hook.) W.E. Higgins].

In l972, Pabst went on with the work and transferred many species before included in the Epidendrum into the genus Encyclia.

In l981, Guido J. F. Pabst, José Luiz de Araujo Moutinho & Antonio Ventura Pinto, reestablished the genus Anacheilium Rchb. ex Hoffmanns and transferred many species into it and did a revision of the genus Hormidium Lindl. Ex Heynh. However Anacheilium remained unknown to most part of the people. They went on calling Epidendrum plants already transferred into this or another genera. As happened as Epidendrum fragrans, vespa and other species.

In l997, reestablishment of the genus Prosthechea Knowles & Westc. by W.E. Higgins.

Between all modifications, the concept of Encyclia is the one which stayed longer but when people got used to the classification of some species inside this genus [specially Encyclia fragrans (Sw.) W.E. Higgins and Encyclia vespa (Vell.) W.E. Higgins] they have their name changed into Prosthechea.

To confuse a little more, some species are so close one with other that, sometimes, the report of the occurrence is not adequate, we misunderstand one with another. Due to the number of varieties found in the same species and, sometimes, inside the same population, one presume a plant found somewhere is a new species and describe as if was. When the misunderstanding is noticed, a correction with the former name is published and the later name (in general) becomes a synonym. Many times, a botanist, taken for granted an information he receives, he describes (in good faith) as occurring in certain place, as seemed to be happened with Hoehne when he described Encyclia doeringii. This plant has been given to him as if it was native of the state of São Paulo. Later, one realized that the plant does not occur in Brazil and has been described already, so Encyclia doeringii Hoehne turn into synonym. In fact, it is Encyclia cordigera (H.B.K.) Dressler which occurs from México to Venezuela.

For that and another reasons and also because Botany is not an exact science and is in constant mutation that we still expect another modifications. The genus remain controversial and all that transference of species and mainly the question of synonyms did not get a consensus between the orchidologists and botanists. In our list, we consider the studies done by Vitorino Paiva Castro Neto and Marco Antonio Campacci published in Icones Orchidacearum Brasiliensis I and posterior publications.

Briefly what distinguishes Encyclia from Prosthechea is the lip which is solded at the base of the column in the first one and in the second, it solded until the middle of the column. In Encyclia, the anther is laterally adhered and in Prosthechea the polineas are up encased forming a third element.

Alagoas

Encyclia
advena (Rchb. f.) Pôrto & Brade
amicta (Lindl. & Rchb. f.) Schltr
bohnkiana V. P. Castro & Campacci
dichroma (Lindl) Schltr
flava (Lindl.) Porto & Brade
gallopavina (Rchb. f.) Pôrto & Brade
oncidioides (Lindl) Schltr
osmantha (Barb Rodr) Schltr
patens (Hook) Porto & Brade
tripartita (Vell.) Hoehne

Prosthechea
alagoensis (Pabst) W.E. Higgins
fragrans (Sw.) W.E. Higgins
glumacea (Lindl.) W.E. Higgins
pygmaea (Hook.) W.E. Higgins

Minas Gerais

Encyclia
advena (Rchb. f.) Pôrto & Brade
alboxanthina Fowl
amicta (Lindl. & Rchb. f.) Schltr
argentinensis (Speg.) Hoehne
bracteata (Barb. Rodr.) Schlt.
bragrancae Ruschi
dichroma (Lindl) Schltr
duveenii Pabst
euosma (Rchb.f.) Pôrto
flava (Lindl.) Porto & Brade
gallopavina (Rchb. f.) Pôrto & Brade
oncidioides (Lindl) Schltr
osmantha (Barb Rodr) Schltr
patens (Hook) Porto & Brade
pauciflora (Barb. Rodr.) Pôrto & Brade
seidelii Pabst
vellozoana Pabst
widgrenii Lindl

Híbridos Naturais
Encylaelia x intermedia Miranda [Encyclia seidelii Pabst x crispata Lindl (Thunb.) Miranda]
Encyclia x verboonenii V. P. Castro & Campacci [Encyclia osmantha (Barb. Rodr.) Schltr. X Encyclia argentinensis (Speg.) Hoehne]


Prosthechea
allemanii (Barb. Rodr.) W.E. Higgins
allemanoides (Hoehne) W.E. Higgins
bulbosa (Vell.) W.E. Higgins
caetensis (Bicalho) W.E. Higgins
calamaria (Lindl.) W.E. Higgins
faresiana (Bicalho) W.E. Higgins
fragrans (Sw.) W.E. Higgins
moojenii (Pabst) W.E. Higgins
papilio (Vell.) W.E. Higgins
pipio (Rchb. f.) W.E. Higgins
pygmaea (Hook.) W.E. Higgins
regnelliana (Hoehne & Schltr.) W.E. Higgins
sessiliflora (Edwall) W.E. Higgins
suzanensis (Hoehne) W.E. Higgins
vespa (Vell.) W.E. Higgins

Paraná

Encyclia
argentinensis (Speg.) Hoehne
oncidioides (Lindl) Schltr
patens (Hook) Porto & Brade
pauciflora (Barb. Rodr.) Pôrto & Brade
widgrenii Lindls
Prosthechea
bulbosa (Vell.) W.E. Higgins
fragrans (Sw.) W.E. Higgins
fausta (Rchb. f. ex Cogn.) W.E. Higgins
glumacea (Lindl.) W.E. Higgins
punctifera (Rchb. f.) W.E. Higgins
vespa (Vell.) W.E. Higginss

Tocantins

Encyclia
argentinensis (Speg.) Hoehne
flava (Lindl.) Porto & Brade
gallopavina (Rchb. f.) Pôrto & Brade
tocantinense V. P. Castro & Campacci

Híbridos Naturais

Encyclia x alcardoi Vitorino Paiva Castro Netto & Guy Chiron [Encyclia flava (Lindl.) Porto & Brade e Encyclia argentinensis (Speg.) Hoehne]

Bibliography:

This list is the result of a extensive research done in the specialized literature and it is not, of course, definitive but it is most updated we could get.

Our special thanks to Vitorino Paiva Castro Neto for his usual disposability to clarify doubts and give us information.

The mainly sources or research were:

- Guido J. F. Pabst, José Luiz de Araujo Moutinho& Antonio Ventura Pinto, Reestablishing of the Anacheilium Rchb. ex Hoffmgg and the revision of the genus Hormidium Lindl. ex Heynh.
- Icones Orchidacearum Brasiliensis I , by Vitorino Paiva Castro Neto and Marco Antonio Campacci

and more:

1) Anna Luiza Ilkiu-Borges, André Luiz de R. Cardoso, Euzamar C da S. Lima, Noé C. B. bom Atzingen    "Carajás uma iniciativa de preservação" Revista Orquidário Volume 13 nº 5.
2) Augusto Fernandes Neves "Ao Longo da Chapada." Revista Orquidário Volume 5 nº 4, l991,
3) Eric A Christenson - Notes on Neotropical Orchidaceae II Lindleyana 11(1):12-26 (1996)
4) Eric A Christenson - Natural Changes in Neotropical Orchidaceae. Lindleyana 2(3): 221-223 (l998)
5) Francisco Miranda, Notas sobre Algumas Novas Espécies de Orquídeas" - Encylaelia. Revista    Orquidário 6 (2): (l992).
6) João Batista F. da Silva "Viajando pela Amazônia I a IV Boletim Caob
7) L.C. Menezes - diversos artigos em Revista Orquidário
8) Luiz de Araujo Pereira, Orquídeas de Alagoas.
9) Luiz de Araujo Pereira, Álbum das Orquídeas de Alagoas, Imprensa Oficial Graciliano Ramos, 2000
10) Pedro Ivo Soares Braga, in Bradea, 170/173- Orquídeas das Campinas da Amazônia Brasileira,  Novas      ocorrências para o Brasil e taxa novas para a Ciência.
11) Pedro Ivo Soares Braga, in Bradea 6(35): 293 (1994) - Orquídeas da Amazônia Brasileira - III
12) Vitorino Paiva C. Neto e Marcos Antonio Campacci , diversos artigos de revista Orquidário e CAOB
13) Vitorino Paiva C. Neto e Marcos Antonio Campacci "Uma Nova Espécie de Encyclia do Estado de      Tocantins" Revista Orquidário Volume 10 nº 3, l996
14) Vitorino Paiva C. Neto e Marcos Antonio Campacci "Uma Nova Espécie de Encyclia do Estado da      Bahia" Revista Orquidário Volume 12 nº 1, l998
15) Revista Orquidário volume 7, nº 3, l993, "Orquídeas do Mato Grosso do Sul"
16) Orquídeas de Carajás = Orchids from Carajás/ Companhia Vale do Rio Doce, pesquisas por Luiz C.      Nepoumuceno, Volmar da Silva Cedivanes, Euzamar C. Silveira, Jair Pereira da Silva, l996.
17) Orchidaceae Brasiliensis - G. F. Pabst & F. Dungs, Alemanha, l977, Vol. I e II.
18) Orchids of Venezuela, An Illustrated Field Guide, Dunsterville and Garay, 1979 , 3 volumes
19) Orquídeas do Estado do Espírito Santo, Augusto Ruschi, Ed. Expressão e Cultura, l986
20) Orquídeas do Alto da Serra da Mata Atlântica Pluvial do Sudeste do Brasil, David Miller & Richard      Warren, fotografias Isabel Moura Miller
21) Segundo Encontro Nacional de Orquidófilos e Orquidólogos, Pernambuco- Brasil (Exped)
     Levantamento das Orquidáceas do Nordeste Oriental do Brasil / A survey of the orchids of the Eastern      Brazilian Northeast, Augusto Burle Gomes Ferreira , Orquídeas do Estado do Mato Grosso, José      Guilherme Aires de Lima
22) Orchiids of Brazil - Jim & Barbara McQueen- The World of Orchids 2 - The Text Publishing Company      Melbourne Australia - 1993
23) The illustrated Encyclopedia of Orchids edited by Alex Pridgeon - Timber Press. .6

All photos in this article are © Sergio Araujo