Roystonea palaea
Encyclopedia
Roystonea palaea is an extinct species of palm
known from fossil
flowers found in the early Miocene
Burdigalian
stage Dominican amber
deposits on the island of Hispaniola
. The species is known from a single staminate flower and a single pistillate flower both preserved in the same piece of amber. The amber specimen bearing the holotype
and paratype
is currently deposited in the collections of the Oregon State University
in Corvallis, Oregon
, as number "Sd–9–101", where it was studied and described by Dr George Poinar
. Dr Poinar published his 2002 type description for R. palaea in the Botanical Journal of the Linnean Society
, Volume 139. The species' second name is taken from the Greek word
palaios meaning "ancient". The amber specimen bearing the flowers was excavated from the La Toca mine northeast of Santiago de los Caballeros
, Dominican Republic
.
R. palaea has been placed in the Arecoideae genus Roystonea
, which has ten modern genera native to the islands of the Caribbean, and to Florida, Central and South America. Many of the characters used to separate modern species of Roystonea, including coloration, are not visible in the preserved flowers. The fossil flowers have darkened to shades of brown, with only the anthers retaining a light whitish color. Of the modern genera the R. palaea flowers are similar in structure, R. oleracea
and R. dunlapiana
both having a similar petal to sepal length ratio. R. palaea is most distinguishable from modern species by the large size of the calyx
. The three species differ in the shape and length of their sepal
s, R. palaea having the longest of the species while R. dunlapiana has the shortest. R. oleracea also possesses longer anthers at 3.5–4.7 mm (0.137795275590551–0.18503937007874 in)which are recurved at the tips, unlike R. palaea, with anthers 1.7–3.1 mm (0.0669291338582677–0.122047244094488 in) and straight. Along with the shorter sepal length R. dunlapiana also has purple anthers, differing from the light-colored anthers of R. palaea.
Of note is the damage which is present on the pistillate flower. One side of the flower is preserved, having the peranth ripped off exposing the center of the flower and the developing fruit, which has two scratches on the exposed side. Dr Poinar proposes that the damages may have occurred due to an herbivore seizing the flower and subsequently dropping it in the soft tree resin, which afterward fossilized. This is supported by many of the modern Roystonea species having oily fruits that are eaten by a number of bird and bat species.
Arecaceae
Arecaceae or Palmae , are a family of flowering plants, the only family in the monocot order Arecales. There are roughly 202 currently known genera with around 2600 species, most of which are restricted to tropical, subtropical, and warm temperate climates...
known from fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
flowers found in the early Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
Burdigalian
Burdigalian
The Burdigalian is, in the geologic timescale, an age or stage in the early Miocene. It spans the time between 20.43 ± 0.05 Ma and 15.97 ± 0.05 Ma...
stage Dominican amber
Dominican amber
Dominican amber is amber from the Dominican Republic. Resin from the extinct species Hymenaea protera is the source of Dominican amber and probably of most amber found in the tropics....
deposits on the island of Hispaniola
Hispaniola
Hispaniola is a major island in the Caribbean, containing the two sovereign states of the Dominican Republic and Haiti. The island is located between the islands of Cuba to the west and Puerto Rico to the east, within the hurricane belt...
. The species is known from a single staminate flower and a single pistillate flower both preserved in the same piece of amber. The amber specimen bearing the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
and paratype
Paratype
Paratype is a technical term used in the scientific naming of species and other taxa of organisms. The exact meaning of the term paratype when it is used in zoology is not the same as the meaning when it is used in botany...
is currently deposited in the collections of the Oregon State University
Oregon State University
Oregon State University is a coeducational, public research university located in Corvallis, Oregon, United States. The university offers undergraduate, graduate and doctoral degrees and a multitude of research opportunities. There are more than 200 academic degree programs offered through the...
in Corvallis, Oregon
Corvallis, Oregon
Corvallis is a city located in central western Oregon, United States. It is the county seat of Benton County and the principal city of the Corvallis, Oregon Metropolitan Statistical Area, which encompasses all of Benton County. As of the 2010 United States Census, the population was 54,462....
, as number "Sd–9–101", where it was studied and described by Dr George Poinar
George Poinar, Jr.
George O. Poinar, Jr. is an entomologist and writer. He is known for popularizing the idea of extracting DNA from insects fossilized in amber, an idea which received widespread attention when adapted by Michael Crichton for the book and movie Jurassic Park.Poinar earned a B.S. and M.S. at Cornell...
. Dr Poinar published his 2002 type description for R. palaea in the Botanical Journal of the Linnean Society
Botanical Journal of the Linnean Society
The Botanical Journal of the Linnean Society is a scientific journal publishing original papers relating to the taxonomy of all plant groups and fungi, including anatomy, biosystematics, cytology, ecology, ethnobotany, electron microscopy, morphogenesis, palaeobotany, palynology and...
, Volume 139. The species' second name is taken from the Greek word
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
palaios meaning "ancient". The amber specimen bearing the flowers was excavated from the La Toca mine northeast of Santiago de los Caballeros
Santiago de los Caballeros
Santiago de los Caballeros is a city in the Dominican Republic. Founded in 1495 during the first wave of European colonization of the New World, today Santiago is the second largest metropolis in the Dominican Republic, located in the north-central region of the Republic known as Cibao valley...
, Dominican Republic
Dominican Republic
The Dominican Republic is a nation on the island of La Hispaniola, part of the Greater Antilles archipelago in the Caribbean region. The western third of the island is occupied by the nation of Haiti, making Hispaniola one of two Caribbean islands that are shared by two countries...
.
R. palaea has been placed in the Arecoideae genus Roystonea
Roystonea
Roystonea is a genus of eleven species of monoecious palms, native to the Caribbean Islands, and the adjacent coasts of Florida, Central and South America. Commonly known as the royal palms, the genus was named for Roy Stone, a U.S. Army engineer...
, which has ten modern genera native to the islands of the Caribbean, and to Florida, Central and South America. Many of the characters used to separate modern species of Roystonea, including coloration, are not visible in the preserved flowers. The fossil flowers have darkened to shades of brown, with only the anthers retaining a light whitish color. Of the modern genera the R. palaea flowers are similar in structure, R. oleracea
Roystonea oleracea
Roystonea oleracea, sometimes known as the Caribbean Royal Palm, palmiste, Imperial palm or cabbage palm, is a species of palm which is native to the Lesser Antilles, northern South America and Trinidad and Tobago.-Description:...
and R. dunlapiana
Roystonea dunlapiana
Roystonea dunlapiana, commonly known as yagua or cabiche is a species of palm which is native to southern Mexico and Central America. It is the only species in the genus Roystonea which is absent from the insular Caribbean.-Description:...
both having a similar petal to sepal length ratio. R. palaea is most distinguishable from modern species by the large size of the calyx
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
. The three species differ in the shape and length of their sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s, R. palaea having the longest of the species while R. dunlapiana has the shortest. R. oleracea also possesses longer anthers at 3.5–4.7 mm (0.137795275590551–0.18503937007874 in)which are recurved at the tips, unlike R. palaea, with anthers 1.7–3.1 mm (0.0669291338582677–0.122047244094488 in) and straight. Along with the shorter sepal length R. dunlapiana also has purple anthers, differing from the light-colored anthers of R. palaea.
Of note is the damage which is present on the pistillate flower. One side of the flower is preserved, having the peranth ripped off exposing the center of the flower and the developing fruit, which has two scratches on the exposed side. Dr Poinar proposes that the damages may have occurred due to an herbivore seizing the flower and subsequently dropping it in the soft tree resin, which afterward fossilized. This is supported by many of the modern Roystonea species having oily fruits that are eaten by a number of bird and bat species.