Smilacaceae
Encyclopedia
Smilacaceae, the greenbrier family, is a family of flowering plants. Up to some decades ago the genera now included in family Smilacaceae were often assigned to a more broadly defined family Liliaceae
, but for the past twenty to thirty years most botanists have accepted Smilacaceae as a distinct family. It is considered that the two families evolved around 55 millions years ago during the Early Paleogene
possibly near the boundary between Paleocene
and Eocene
. One characteristic that distinguishes Smilacaceae from most of the other members of the Liliaceae-like Liliales is that it has true vessels in its conducting tissue. Another is that the veins of the leaves, between major veins, are reticulate (net-shaped), rather than parallel as in most monocots.
, of 2003 (unchanged from the APG system
, of 1998), recognizes this family and places it in the order Liliales
, in the clade
monocots. Within APG II it is a family of probably two genera Heterosmilax and the larger Smilax
. However more recently Heterosmilax has been found to have arisen from within the ranks for Smilax.
The family occurs throughout the tropical and warm temperate regions of the world. Members of this family typically have woody roots and a climbing or vining form. Some have woody vining stems, often with thorns, while others are herb
aceous above ground and thornless.
Other placements of the family include:
and nearly indistinguishable vegetatively, their flowers differ markedly. The flower of Heterosmilax is fused into a deep bottle-shaped tube containing prominent nectaries, its stamen
s are also connected at the bottom. Whereas flowers of Smilax are typically small with unfused floral parts. Smilax is a much larger and more widely distributed genus than Heterosmilax. Heterosmilax has only twelve species
which are confined to China
, Japan
, tropical Asia
, Singapore
, Malaysia, and the surrounding islands.
Some taxonomists separate the herbaceous plants native to North America in Smilax
as the genus Nemexia
, which is known for its malodorous flower
s. Smilax would then be left with only plants of a woody, vining form with thorns. However the Flora of North America
does not recognise Nemexia, nor does the AP-site.
Liliaceae
The Liliaceae, or the lily family, is a family of monocotyledons in the order Liliales. Plants in this family have linear leaves, mostly with parallel veins but with several having net venation , and flower arranged in threes. Several have bulbs, while others have rhizomes...
, but for the past twenty to thirty years most botanists have accepted Smilacaceae as a distinct family. It is considered that the two families evolved around 55 millions years ago during the Early Paleogene
Paleogene
The Paleogene is a geologic period and system that began 65.5 ± 0.3 and ended 23.03 ± 0.05 million years ago and comprises the first part of the Cenozoic Era...
possibly near the boundary between 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...
and Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
. One characteristic that distinguishes Smilacaceae from most of the other members of the Liliaceae-like Liliales is that it has true vessels in its conducting tissue. Another is that the veins of the leaves, between major veins, are reticulate (net-shaped), rather than parallel as in most monocots.
Classification
The APG II systemAPG II system
The APG II system of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Group. It was a revision of the first APG system, published in 1998, and was superseded in 2009...
, of 2003 (unchanged from the APG system
APG system
The APG system of plant classification is the first, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in 1998 by the Angiosperm Phylogeny Group. It was superseded in 2003 by a revision, the APG II system, and then in 2009 by a further...
, of 1998), recognizes this family and places it in the order Liliales
Liliales
Liliales is an order of monocotyledonous flowering plants. This order of necessity includes the family Liliaceae, but both the family and the order have had a widely disputed history, with the circumscription varying greatly from one taxonomist to another...
, in the 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...
monocots. Within APG II it is a family of probably two genera Heterosmilax and the larger Smilax
Smilax
Smilax is a genus of about 300-350 species, found in temperate zones, tropics and subtropics worldwide. In China for example about 80 are found , while there are 20 in North America north of Mexico...
. However more recently Heterosmilax has been found to have arisen from within the ranks for Smilax.
The family occurs throughout the tropical and warm temperate regions of the world. Members of this family typically have woody roots and a climbing or vining form. Some have woody vining stems, often with thorns, while others are herb
Herb
Except in botanical usage, an herb is "any plant with leaves, seeds, or flowers used for flavoring, food, medicine, or perfume" or "a part of such a plant as used in cooking"...
aceous above ground and thornless.
Other placements of the family include:
- The Cronquist systemCronquist systemThe Cronquist system is a taxonomic classification system of flowering plants. It was developed by Arthur Cronquist in his texts An Integrated System of Classification of Flowering Plants and The Evolution and Classification of Flowering Plants .Cronquist's system places flowering plants into two...
, of 1981, recognized this family and placed it in order LilialesLilialesLiliales is an order of monocotyledonous flowering plants. This order of necessity includes the family Liliaceae, but both the family and the order have had a widely disputed history, with the circumscription varying greatly from one taxonomist to another...
, in subclass LiliidaeLiliidaeLiliidae is a botanical name at the rank of subclass. Circumscription of the subclass will vary with the taxonomic system being used ; the only requirement being that it includes the family Liliaceae....
in class LiliopsidaLiliopsidaLiliopsida is a botanical name for the class containing the family Liliaceae . It is considered synonymous with the name monocotyledon. Publication of the name is credited to Scopoli : see author citation...
[=monocotyledons] of division Magnoliophyta [=angiosperms]. - The Reveal systemReveal systemA modern system of plant taxonomy, the Reveal system of plant classification was drawn up by the botanist J.L. Reveal , professor emeritus at the Norton Brown Herbarium, Maryland .The last update of the system was made in 1999...
recognized this family and placed it in order Smilacales, in subclass Liliidae which is placed as in the Cronquist system. - The Thorne system (1992)Thorne system (1992)A modern system of plant taxonomy, the Thorne system of plant classification was drawn up by the botanist Robert F. Thorne . He replaced it in 2000 with a new system. These two systems were published in:...
also recognized this family, and placed it in order DioscorealesDioscorealesDioscoreales is a botanical name for an order of flowering plants. Of necessity it contains the family Dioscoreaceae.In the APG II system, of 2003, this order was placed in the clade monocots and comprised the families Burmanniaceae, Dioscoreaceae and Nartheciaceae.Under the APG system of 1998,...
in superorder LilianaeLilianaeLilianae is a botanical name, in use for a superorder . Such a superorder will of necessity include the family Liliaceae...
in subclass LiliidaeLiliidaeLiliidae is a botanical name at the rank of subclass. Circumscription of the subclass will vary with the taxonomic system being used ; the only requirement being that it includes the family Liliaceae....
[=monocotyledons] of class MagnoliopsidaMagnoliopsidaMagnoliopsida is a valid botanical name for a class of flowering plants. By definition the class will include the family Magnoliaceae, but its circumscription can otherwise vary, being more inclusive or less inclusive depending upon the classification system being discussed.-Cronquist and...
[=angiosperms]. - The Dahlgren systemDahlgren systemOne of the modern systems of plant taxonomy, the Dahlgren system was published by monocot specialist Rolf Dahlgren. His wife Gertrud Dahlgren carried on after his death.According to the extensive listing by Professor Reveal One of the modern systems of plant taxonomy, the Dahlgren system was...
treated it as did the Thorne system (1992): see above.
Characteristics
Members of this family can be herbaceous to "woody" vines. They grow from this rhizomes and are often armed with prickles on the stems and/or leaves. Leaves are alternate and simple; and entire to spinose-serrate. Some members of this family have coriaceous (leathery) leaves. Venation of the leaves may be palmate to reticulate. A pair of tendrils often appear near the base of the petiole. The inflorescence type for members of this family is an umbel. The flowers are inconspicuous, radial and unisexual. The flowers are made of 6 tepals, 6 stamens and 3 carpels. The fruit type of all members of Smilacaceae is a berry. The number of seeds per berry is 1-3. Nectaries are located at the base of the tepals.Genera
While both genera are dioeciousDioecious
Dioecy is the property of a group of biological organisms that have males and females, but not members that have organs of both sexes at the same time. I.e., those whose individual members can usually produce only one type of gamete; each individual organism is thus distinctly female or male...
and nearly indistinguishable vegetatively, their flowers differ markedly. The flower of Heterosmilax is fused into a deep bottle-shaped tube containing prominent nectaries, its stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s are also connected at the bottom. Whereas flowers of Smilax are typically small with unfused floral parts. Smilax is a much larger and more widely distributed genus than Heterosmilax. Heterosmilax has only twelve species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
which are confined to 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...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, tropical Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, Singapore
Singapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...
, Malaysia, and the surrounding islands.
Some taxonomists separate the herbaceous plants native to North America in Smilax
Smilax
Smilax is a genus of about 300-350 species, found in temperate zones, tropics and subtropics worldwide. In China for example about 80 are found , while there are 20 in North America north of Mexico...
as the genus Nemexia
Nemexia
Smilax sect. Nemexia is a section of plants in the family Smilacaceae. It consists of the herbaceous plants within the genus Smilax. Smilax species fall into two groups with distinctive morphologies: one group has woody perennial stems with thorns and a vining habit, while the other group has...
, which is known for its malodorous 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. Smilax would then be left with only plants of a woody, vining form with thorns. However the Flora of North America
Flora of North America
The Flora of North America North of Mexico is a multivolume work describing the native plants of North America. These days much of the Flora is available . The work is expected to fill 30 volumes when completed...
does not recognise Nemexia, nor does the AP-site.
External links
- Smilacaceae in L. Watson and M.J. Dallwitz (1992 onwards). The families of flowering plants: descriptions, illustrations, identification, information retrieval. Version: 9 March 2006. http://delta-intkey.com.
- links at CSDL, Texas