''Palaeoraphe'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus of palms, represented by one species, ''Palaeoraphe dominicana'' from early Miocene Burdigalian stage

Dominican amber Dominican amber is amber from the Dominican Republic derived from resin of the extinct tree ''Hymenaea protera''. Dominican amber differentiates itself from Baltic amber by being nearly always transparent, and it has a higher number of fossil incl ...

deposits on the island of

Hispaniola Hispaniola (, also ; es, La Española; Latin and french: Hispaniola; ht, Ispayola; tnq, Ayiti or Quisqueya) is an island in the Caribbean that is part of the Greater Antilles. Hispaniola is the most populous island in the West Indies, and th ...

, in the modern-day Dominican Republic.

Discovery and naming

The genus is known from a single, diameter, full flower. The holotype is currently deposited in the collections of the Oregon State University in

Corvallis, Oregon Corvallis ( ) is a city and the county seat of Benton County in central western Oregon, United States. It is the principal city of the Corvallis, Oregon Metropolitan Statistical Area, which encompasses all of Benton County. As of the 2020 United ...

, as number "Sd–9–158", where it was studied and described by Dr George Poinar. Dr Poinar published his 2002

type description A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...

for ''Palaeoraphe'' in the '' Botanical Journal of the Linnean Society'' volume number 139. The genus name is a combination of the Greek word ''palaios'' meaning "ancient" and '' Raphia'' a genus of palm, while the species name ''dominicana'' references the Dominican Republic, where the fossil was discovered. The type specimen was excavated from the La Toca mine northeast of Santiago de los Caballeros.

Taxonomy

''Palaeoraphe'' has been placed in the

Corypheae Corypheae is a tribe of palm trees in the subfamily Coryphoideae. In previous classifications, tribe Corypheae included four subtribes: Coryphinae, Livistoninae, Thrinacinae and Sabalinae, but recent phylogenetic studies have led to the genera ...

subtribe

Livistoninae Livistoninae is a subtribe of plants in the family Arecaceae. Species in the subtribe are found throughout Indomalaya and Australasia. Genera in the subtribe are: *''Livistona'' – Indomalaya, Australasia, Gulf of Aden *''Licuala'' – Indoch ...

, which has twelve modern genera found in both the Old World and the New World. Of the three modern genera, the ''Palaeoraphe'' flower is similar in character to ''

Brahea ''Brahea'' is a genus of palms in the family Arecaceae. They are commonly referred to as hesper palms and are endemic to Mexico and Central America.Govaerts, R. & Dransfield, J. (2005). World Checklist of Palms: 1-223. The Board of Trustees of t ...

'', ''

Acoelorrhaphe ''Acoelorrhaphe'' is a genus of palms with single species ''Acoelorrhaphe wrightii'', known as the Paurotis palm, Everglades palm or Madeira palm in EnglishWorld Checklist of Palms''Acoelorrhaphe''Germplasm Resources Information Network''Acoelor ...

'' and '' Colpothrinax'', with the structure being closest in structure to that of ''Brahea''. Both genera have distinct sepals,

petal Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...

s with furrows facing the axis of the flower, and similarly shaped and sized

anther The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filam ...

s. However, the two genera can be differentiated by the stigmas, which are united for their entire length in ''Brahea'', and by the more relaxed positioning of the anthers in ''Palaeoraphe''. The flower of ''P. dominicana'' is a

calyx Calyx or calyce (plural "calyces"), from the Latin ''calix'' which itself comes from the Ancient Greek ''κάλυξ'' (''kálux'') meaning "husk" or "pod", may refer to: Biology * Calyx (anatomy), collective name for several cup-like structures ...

of three broad sepals with irregular to fringed apices. The three petals are joined at their bases and of the six stamins, those paired with petals are relaxed into depressions on the petal surface, while the remaining three stamins are partially erect. It is proposed by Dr. Poinar that ''Palaeoraphe'' may have been a stenotopic genus which was restricted to the Greater Antilles and possibly to just the island of Hispaniola. The extinction of ''Palaeoraphe'' may have been caused by floral and faunal shifts during the Pliocene and Pleistocene.

References

{{Taxonbar, from1=Q262088, from2=Q3360793 Monotypic Arecaceae genera Miocene plants Miocene life of North America Prehistoric angiosperm genera Neogene Dominican Republic Flora of Hispaniola Fossil taxa described in 2002 Prehistoric plants of North America Coryphoideae Taxa named by George Poinar Jr.