Exbucklandia
Encyclopedia
Exbucklandia is a genus
of flowering plant
s in the family
Hamamelidaceae
. They are medium to large trees whose natural range
is from eastern India
through southern China
and southward through the Malay Peninsula
. In India and China, they are widely cultivated for their impressive foliage and valuable lumber
. A few have been grown in the southernmost parts of the United States
. To speakers of English
, Exbucklandia is generally known as the Pipli tree, from the Bengal
i name for the species Exbucklandia populnea.
is usually by seed, but cuttings have been successful under favorable conditions. Plantation
s of the young trees must be fenced against cattle
and deer
which eat whatever leaves they can reach. If Exbucklandia is grown in the open, the trunk
forks and branch
es are retained close to the ground. In the forest
, where it usually grows, the trunk is single, straight, and free of branches for 9 to 18 meters. Saplings grow slowly for the first few years, then more quickly later on.
have ever been published in Exbucklandia. These are Exbucklandia populnea, Exbucklandia tonkinensis, and Exbucklandia longipetala. The specific epithets refer to poplar
s, Tonkin
, and long petals.
Exbucklandia populnea is found throughout the entire range
of the genus. Exbucklandia tonkinensis is native
to southeastern China
, Laos
, and northern Vietnam
. Exbucklandia longipetala has a much more restricted range, being known only from the Guangxi
and Guizhou
provinces
of China.
Further field work will be needed to determine whether these are three distinct entities and whether the specimen
s assigned to Exbucklandia populnea represent a single species or two. Consequently, estimates of the number of species range from two to four.
Exbucklandias are evergreen
tree
s. Exbucklandia populnea and Exbucklandia tonkinensis are usually 16 to 20 meters in height, occasionally reaching 30 meters. The largest known individual of Exbucklandia populnea grew to 45 meters in the Darjeeling Hills
of India. The usual height of Exbucklandia longipetala is not known. The twigs
have conspicuous nodes.
The leaves
are attractively reddish when immature. They are arranged alternately on the stems, an arrangement unusual for Hamamelidaceae
. The petioles
are long and the leaves flutter in even a light breeze, like the leaves of poplar
s. The poplar petiole is flattened, and in cross section
, it is long in the vertical direction. Whether Exbucklandia has the same sort of petiole has not been recorded.
The leaf blade is simple, and sometimes has three pointed lobes, or rarely, five. It is thickly leathery and its margin is entire
. The venation is palmate, with the secondary veins radiating from the apex of the petiole. The stipule
s are large and coherent; soon falling away.
Each inflorescence
has 7 to 16 flower
s and is located in the axil of a leaf. The flowers are small and bisexual. Sepal
s are completely lacking. Petal
s are often absent, but are small and white when present. Some authors have interpreted what appear to be petals as petaloid staminode
s.
The stamen
s are 10 to 15 in number. The anthers are basifixed, as in all of Hamamelidaceae. Each theca
has one sporangium
, whereas for most angiosperms, there are two. The thecae open
by one valve.
The ovary
is half-inferior and, as in the rest of the family, consists of two carpels. The number of ovule
s in each carpel has been reported as five or six and as six to eight. What some authors have loosely called styles are actually styluli. These are separate by definition, channeling the pollen tube
s that invade them into only one carpel. Each stigma
is somewhat decurrent
down one side of its stylulus.
The fruit
is a 4-valved capsule
. The two locule
s separate, and each splits into two valves. Each locule contains five to seven seeds. The upper four or five are sterile and wingless. The lowest one or two are fertile and narrowly winged. The seeds are light and can travel far in a strong wind.
formed the most basal
clade
in the family. Chunia bucklandioides, a rare tree from Hainan
which has never been sampled for DNA
, might also be a member of this clade. Vegetatively, it is hard to distinguish from Exbucklandia, while florally, it is intermediate between Exbucklandia and Mytilaria. The morphology
of Chunia indicates that if it is not in the clade with Exbucklandia and Rhodoleia, then it either forms its own clade or it is sister to Mytilaria.
than it is today. Four species are known only from fossil
s. Exbucklandia oregonensis grew in the northwestern United States
during the Oligocene
and Miocene
epochs
. Exbucklandia microdictya is known from Paleocene
deposits near Altay City in Xinjiang
Province, China. Exbucklandia miocenica is a Miocene species from Yunnan
Province, China. Exbucklandia tengchongensis is known from fossils recovered from a diatomite mine in Tengchong County
in Yunnan, China. It dates from the Pliocene
epoch.
in the "Tentamen" part of Flora der Vorwelt, the classic paleobotanical
work by Kaspar Maria von Sternberg
. The name has been attributed to Carl Borivoj Presl as well as to Sternberg. In 1836, Robert Brown
, unaware that the name had already been taken, published the name Bucklandia populnea for the tree now known as Exbucklandia populnea to honor the Reverend William Buckland
, an English geologist
and paleontologist. In the case of Bucklandia, Brown did not meet the requirements of valid publication, but the name was validated by William Griffith
, posthumously, in 1847. In 1924, Paul Henri Lecomte
named a second species, Bucklandia tonkinensis. For more than 100 years, it remained unnoticed that two genera of plants had received the name Bucklandia. This conflict was finally resolved by Roland W. Brown in 1946. At that time, Brown wrote, "Inasmuch as the 1825 cycadeoid name has priority, the witchhazel genus requires a new name. For this purpose, I propose Exbucklandia, the derivation of which is obvious." Unaware of Brown's paper, Cornelis G.G.J. van Steenis sought to resolve the conflict of names in 1952 by replacing Bucklandia with Symingtonia. He published a notice of this oversight in 1954, acknowledging the priority of Exbucklandia over Symingtonia. In that paper, van Steenis transferred the second species to Exbucklandia, because Roland Brown had not explicitly done so in 1946. Thus van Steenis originated the combination
Exbucklandia tonkinensis, but not validly, because he failed to cite
the publication of the basionym
as the ICBN has required since 1953. In 1959, Hung-Ta Chang validly made the combination Exbucklandia tonkinensis. In that same paper, Chang described and named the third species, Exbucklandia longipetala. A taxonomic history and a description of each of the three species can be found in Flora of China volume 9.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
s in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Hamamelidaceae
Hamamelidaceae
The Hamamelidaceae is a family of flowering plants in the order Saxifragales, including 27 genera and about 80-90 species, all shrubs and small trees...
. They are medium to large trees whose natural range
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
is from eastern India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
through southern China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
and southward through the Malay Peninsula
Malay Peninsula
The Malay Peninsula or Thai-Malay Peninsula is a peninsula in Southeast Asia. The land mass runs approximately north-south and, at its terminus, is the southern-most point of the Asian mainland...
. In India and China, they are widely cultivated for their impressive foliage and valuable lumber
Lumber
Lumber or timber is wood in any of its stages from felling through readiness for use as structural material for construction, or wood pulp for paper production....
. A few have been grown in the southernmost parts of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. To speakers of English
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
, Exbucklandia is generally known as the Pipli tree, from the Bengal
Bengal
Bengal is a historical and geographical region in the northeast region of the Indian Subcontinent at the apex of the Bay of Bengal. Today, it is mainly divided between the sovereign land of People's Republic of Bangladesh and the Indian state of West Bengal, although some regions of the previous...
i name for the species Exbucklandia populnea.
Cultivation
PropagationPlant propagation
Plant propagation is the process of creating new plants from a variety of sources: seeds, cuttings, bulbs and other plant parts. Plant propagation can also refer to the artificial or natural dispersal of plants.-Sexual propagation :...
is usually by seed, but cuttings have been successful under favorable conditions. Plantation
Plantation
A plantation is a long artificially established forest, farm or estate, where crops are grown for sale, often in distant markets rather than for local on-site consumption...
s of the young trees must be fenced against cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...
and deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...
which eat whatever leaves they can reach. If Exbucklandia is grown in the open, the trunk
Trunk (botany)
In botany, trunk refers to the main wooden axis of a tree that supports the branches and is supported by and directly attached to the roots. The trunk is covered by the bark, which is an important diagnostic feature in tree identification, and which often differs markedly from the bottom of the...
forks and branch
Branch
A branch or tree branch is a woody structural member connected to but not part of the central trunk of a tree...
es are retained close to the ground. In the forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
, where it usually grows, the trunk is single, straight, and free of branches for 9 to 18 meters. Saplings grow slowly for the first few years, then more quickly later on.
Species
Only three species namesBinomial nomenclature
Binomial nomenclature is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages...
have ever been published in Exbucklandia. These are Exbucklandia populnea, Exbucklandia tonkinensis, and Exbucklandia longipetala. The specific epithets refer to poplar
Poplar
Populus is a genus of 25–35 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar , aspen, and cottonwood....
s, Tonkin
Tonkin
Tonkin , also spelled Tongkin, Tonquin or Tongking, is the northernmost part of Vietnam, south of China's Yunnan and Guangxi Provinces, east of northern Laos, and west of the Gulf of Tonkin. Locally, it is known as Bắc Kỳ, meaning "Northern Region"...
, and long petals.
Exbucklandia populnea is found throughout the entire range
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
of the genus. Exbucklandia tonkinensis is native
Indigenous (ecology)
In biogeography, a species is defined as native to a given region or ecosystem if its presence in that region is the result of only natural processes, with no human intervention. Every natural organism has its own natural range of distribution in which it is regarded as native...
to southeastern China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, Laos
Laos
Laos Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ Sathalanalat Paxathipatai Paxaxon Lao, officially the Lao People's Democratic Republic, is a landlocked country in Southeast Asia, bordered by Burma and China to the northwest, Vietnam to the east, Cambodia to the south and Thailand to the west...
, and northern Vietnam
Vietnam
Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...
. Exbucklandia longipetala has a much more restricted range, being known only from the Guangxi
Guangxi
Guangxi, formerly romanized Kwangsi, is a province of southern China along its border with Vietnam. In 1958, it became the Guangxi Zhuang Autonomous Region of the People's Republic of China, a region with special privileges created specifically for the Zhuang people.Guangxi's location, in...
and Guizhou
Guizhou
' is a province of the People's Republic of China located in the southwestern part of the country. Its provincial capital city is Guiyang.- History :...
provinces
Province (China)
A province, in the context of Chinese government, is a translation of sheng formally provincial level divisions, which is an administrative division. Provinces, municipalities, autonomous regions, and the special administrative regions, make up the four types of province of administrative division...
of China.
Further field work will be needed to determine whether these are three distinct entities and whether the specimen
Specimen
A specimen is a portion/quantity of material for use in testing, examination, or study.BiologyA laboratory specimen is an individual animal, part of an animal, a plant, part of a plant, or a microorganism, used as a representative to study the properties of the whole population of that species or...
s assigned to Exbucklandia populnea represent a single species or two. Consequently, estimates of the number of species range from two to four.
Description
The following description of Exbucklandia applies only to extant species and does not necessarily hold for species known only from the fossil record. It is adapted from the description in Flora of China volume 9, with the exceptions noted.Exbucklandias are evergreen
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
s. Exbucklandia populnea and Exbucklandia tonkinensis are usually 16 to 20 meters in height, occasionally reaching 30 meters. The largest known individual of Exbucklandia populnea grew to 45 meters in the Darjeeling Hills
Darjeeling Himalayan hill region
Darjeeling Himalayan hill region or Darjeeling Himalaya is the mountainous area on the North-Western side of the state of West Bengal in India. This region belongs to the Eastern Himalaya range. The whole of the Darjeeling district except the Siliguri subdivision constitutes the region. It arises...
of India. The usual height of Exbucklandia longipetala is not known. The twigs
Plant stem
A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...
have conspicuous nodes.
The leaves
Leaves
-History:Vocalist Arnar Gudjonsson was formerly the guitarist with Mower, and he was joined by Hallur Hallsson , Arnar Ólafsson , Bjarni Grímsson , and Andri Ásgrímsson . Late in 2001 they played with Emiliana Torrini and drew early praise from the New York Times...
are attractively reddish when immature. They are arranged alternately on the stems, an arrangement unusual for Hamamelidaceae
Hamamelidaceae
The Hamamelidaceae is a family of flowering plants in the order Saxifragales, including 27 genera and about 80-90 species, all shrubs and small trees...
. The petioles
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
are long and the leaves flutter in even a light breeze, like the leaves of poplar
Poplar
Populus is a genus of 25–35 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar , aspen, and cottonwood....
s. The poplar petiole is flattened, and in cross section
Cross section (geometry)
In geometry, a cross-section is the intersection of a figure in 2-dimensional space with a line, or of a body in 3-dimensional space with a plane, etc...
, it is long in the vertical direction. Whether Exbucklandia has the same sort of petiole has not been recorded.
The leaf blade is simple, and sometimes has three pointed lobes, or rarely, five. It is thickly leathery and its margin is entire
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
. The venation is palmate, with the secondary veins radiating from the apex of the petiole. The stipule
Stipule
In botany, stipule is a term coined by Linnaeus which refers to outgrowths borne on either side of the base of a leafstalk...
s are large and coherent; soon falling away.
Each inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
has 7 to 16 flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s and is located in the axil of a leaf. The flowers are small and bisexual. 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 are completely lacking. Petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...
s are often absent, but are small and white when present. Some authors have interpreted what appear to be petals as petaloid staminode
Staminode
In botany, a staminode is an often rudimentary, sterile or abortive stamen. This means that it does not produce pollen. Staminodes are frequently inconspicuous and stamen-like, usually occurring at the inner whorl of the flower, but are also sometimes long enough to protrude from the...
s.
The stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s are 10 to 15 in number. The anthers are basifixed, as in all of Hamamelidaceae. Each theca
Theca
A theca refers to any case, covering, or sheath.In botany, the theca of an angiosperm consists a pair of microsporangia that are adjacent to each other and share a common area of dehiscence called the stomium. Any part of a microsporophyll that bears microsporangia is called an anther. Most...
has one sporangium
Sporangium
A sporangium is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. All plants, fungi, and many other lineages form sporangia at some point in their life cycle...
, whereas for most angiosperms, there are two. The thecae open
Dehiscence
Dehiscence can refer to:*Dehiscence is the spontaneous opening at maturity of a plant structure, such as a fruit, anther, or sporangium, to release its contents.*Wound dehiscence is a previously closed wound reopening....
by one valve.
The ovary
Ovary (plants)
In the flowering plants, an ovary is a part of the female reproductive organ of the flower or gynoecium. Specifically, it is the part of the pistil which holds the ovule and is located above or below or at the point of connection with the base of the petals and sepals...
is half-inferior and, as in the rest of the family, consists of two carpels. The number of ovule
Ovule
Ovule means "small egg". In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integument forming its outer layer, the nucellus , and the megaspore-derived female gametophyte in its center...
s in each carpel has been reported as five or six and as six to eight. What some authors have loosely called styles are actually styluli. These are separate by definition, channeling the pollen tube
Pollen tube
The pollen tubes is the male gametophyte of seed plants that acts as a conduit to transport the male sperm cells from the pollen grain, either from the stigma to the ovules at the base of the pistil, or directly through ovule tissue in some gymnosperms .After pollination, the pollen tube...
s that invade them into only one carpel. Each stigma
Stigma (botany)
The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. The stigma receives pollen at pollination and it is on the stigma that the pollen grain germinates. The stigma is adapted to catch and trap pollen with various hairs, flaps, or sculpturings...
is somewhat decurrent
Decurrent
Decurrent is a term used in botany and mycology to describe plant or fungal parts that extend downward.In botany, the term is most often applied to leaf blades that partly wrap or have wings around the stem or petiole and extend down along the stem...
down one side of its stylulus.
The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
is a 4-valved capsule
Capsule (fruit)
In botany a capsule is a type of simple, dry fruit produced by many species of flowering plants. A capsule is a structure composed of two or more carpels that in most cases is dehiscent, i.e. at maturity, it splits apart to release the seeds within. A few capsules are indehiscent, for example...
. The two locule
Locule
A locule is a small cavity or compartment within an organ or part of an organism ....
s separate, and each splits into two valves. Each locule contains five to seven seeds. The upper four or five are sterile and wingless. The lowest one or two are fertile and narrowly winged. The seeds are light and can travel far in a strong wind.
Affinities
The phylogeny of Hamamelidaceae has not been resolved with much certainty, but in one recent molecular phylogenetic study, Exbucklandia and RhodoleiaRhodoleia
Rhodoleia is a genus of plant in family Hamamelidaceae. Together with its sister genus Exbucklandia, Rhodoleia forms the sister clade to the other 25 genera of Hamamelidaceae. Flowers of Rhodoleia are bird-pollinated...
formed the most basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
in the family. Chunia bucklandioides, a rare tree from Hainan
Hainan
Hainan is the smallest province of the People's Republic of China . Although the province comprises some two hundred islands scattered among three archipelagos off the southern coast, of its land mass is Hainan Island , from which the province takes its name...
which has never been sampled for DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
, might also be a member of this clade. Vegetatively, it is hard to distinguish from Exbucklandia, while florally, it is intermediate between Exbucklandia and Mytilaria. The morphology
Plant morphology
Plant morphology or phytomorphology is the study of the physical form and external structure of plants. This is usually considered distinct from plant anatomy, which is the study of the internal structure of plants, especially at the microscopic level...
of Chunia indicates that if it is not in the clade with Exbucklandia and Rhodoleia, then it either forms its own clade or it is sister to Mytilaria.
Evolution
Exbucklandia was once more widely distributedSpecies distribution
Species distribution is the manner in which a biological taxon is spatially arranged. Species distribution is not to be confused with dispersal, which is the movement of individuals away from their area of origin or from centers of high population density. A similar concept is the species range. A...
than it is today. Four species are known only from fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s. Exbucklandia oregonensis grew in the northwestern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
during the Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
and 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...
epochs
Series (stratigraphy)
Series are subdivisions of rock layers made based on the age of the rock and corresponding to the dating system unit called an epoch, both being formally defined international conventions of the geological timescale. A series is therefore a sequence of rock depositions defining a...
. Exbucklandia microdictya is known from Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...
deposits near Altay City in Xinjiang
Xinjiang
Xinjiang is an autonomous region of the People's Republic of China. It is the largest Chinese administrative division and spans over 1.6 million km2...
Province, China. Exbucklandia miocenica is a Miocene species from Yunnan
Yunnan
Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
Province, China. Exbucklandia tengchongensis is known from fossils recovered from a diatomite mine in Tengchong County
Tengchong County
-Economy:Tengchong's industry and handicraft work were fostered during the Ming and Qing Dynasties, nearly 400 years ago. Factories and workshops were set up first by importing equipment from abroad. Earlier products included textile goods, leather, soaps, battery, cigarettes, matches, etc. They...
in Yunnan, China. It dates from the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
epoch.
History
In 1825, the name Bucklandia was published for a fossil cycadCycad
Cycads are seed plants typically characterized by a stout and woody trunk with a crown of large, hard and stiff, evergreen leaves. They usually have pinnate leaves. The individual plants are either all male or all female . Cycads vary in size from having a trunk that is only a few centimeters...
in the "Tentamen" part of Flora der Vorwelt, the classic paleobotanical
Paleobotany
Paleobotany, also spelled as palaeobotany , is the branch of paleontology or paleobiology dealing with the recovery and identification of plant remains from geological contexts, and their use for the biological reconstruction of past environments , and both the evolutionary history of plants, with a...
work by Kaspar Maria von Sternberg
Kaspar Maria von Sternberg
Kaspar Maria von Sternberg , 1761, Prague – 1838, Březina Castle, was a Bohemian theologian, mineralogist, geognost, entomologist and botanist. He is known as the Father of Paleobotany....
. The name has been attributed to Carl Borivoj Presl as well as to Sternberg. In 1836, Robert Brown
Robert Brown (botanist)
Robert Brown was a Scottish botanist and palaeobotanist who made important contributions to botany largely through his pioneering use of the microscope...
, unaware that the name had already been taken, published the name Bucklandia populnea for the tree now known as Exbucklandia populnea to honor the Reverend William Buckland
William Buckland
The Very Rev. Dr William Buckland DD FRS was an English geologist, palaeontologist and Dean of Westminster, who wrote the first full account of a fossil dinosaur, which he named Megalosaurus...
, an English geologist
Geologist
A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes and history that has shaped it. Geologists usually engage in studying geology. Geologists, studying more of an applied science than a theoretical one, must approach Geology using...
and paleontologist. In the case of Bucklandia, Brown did not meet the requirements of valid publication, but the name was validated by William Griffith
William Griffith (botanist)
William Griffith was a British doctor, naturalist, and botanist.Griffith's botanical publications are from India and Burma. After a brief stay in Madras, he was assigned as a Civil Surgeon to Tenasserim, Burma, where he studied local plants and made collecting trips to the Barak River valley in...
, posthumously, in 1847. In 1924, Paul Henri Lecomte
Paul Henri Lecomte
Paul Henri Lecomte was a French botanist.In 1884, after attaining a number of degrees, Lecomte became a professor at Lycée Saint-Louis in Paris...
named a second species, Bucklandia tonkinensis. For more than 100 years, it remained unnoticed that two genera of plants had received the name Bucklandia. This conflict was finally resolved by Roland W. Brown in 1946. At that time, Brown wrote, "Inasmuch as the 1825 cycadeoid name has priority, the witchhazel genus requires a new name. For this purpose, I propose Exbucklandia, the derivation of which is obvious." Unaware of Brown's paper, Cornelis G.G.J. van Steenis sought to resolve the conflict of names in 1952 by replacing Bucklandia with Symingtonia. He published a notice of this oversight in 1954, acknowledging the priority of Exbucklandia over Symingtonia. In that paper, van Steenis transferred the second species to Exbucklandia, because Roland Brown had not explicitly done so in 1946. Thus van Steenis originated the combination
Binomial nomenclature
Binomial nomenclature is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages...
Exbucklandia tonkinensis, but not validly, because he failed to cite
Citation
Broadly, a citation is a reference to a published or unpublished source . More precisely, a citation is an abbreviated alphanumeric expression Broadly, a citation is a reference to a published or unpublished source (not always the original source). More precisely, a citation is an abbreviated...
the publication of the basionym
Basionym
Basionym is a term used in botany, regulated by the International Code of Botanical Nomenclature...
as the ICBN has required since 1953. In 1959, Hung-Ta Chang validly made the combination Exbucklandia tonkinensis. In that same paper, Chang described and named the third species, Exbucklandia longipetala. A taxonomic history and a description of each of the three species can be found in Flora of China volume 9.
External links
- http://www.ipni.org/ipni/advPlantNameSearch.do;jsessionid=DA16D49CD8CCED9552FA8CC0C3535045?find_family=&find_genus=Exbucklandia+&find_species=&find_infrafamily=&find_infragenus=&find_infraspecies=&find_authorAbbrev=&find_includePublicationAuthors=on&find_includePublicationAuthors=off&find_includeBasionymAuthors=on&find_includeBasionymAuthors=off&find_publicationTitle=&find_isAPNIRecord=on&find_isAPNIRecord=false&find_isGCIRecord=on&find_isGCIRecord=false&find_isIKRecord=on&find_isIKRecord=false&find_rankToReturn=all&output_format=normal&find_sortByFamily=on&find_sortByFamily=off&query_type=by_query&back_page=plantsearchExbucklandia at IPNI]
- CRC World Dictionary of Plant Names: D-L At: Botany & Plant Science At: Life Science At: CRC Press
- Jacobson's Plant of the Month Jan09 At: Jacobson's Plant of the Month series
- Oregon Oligocene flora
- Tertiary Washington