Triggerplant
Encyclopedia
Stylidium is a genus of dicotyledon
ous plant
s that belong to the family Stylidiaceae
. The genus name Stylidium is derived from the Greek στύλος or stylos (column or pillar), which refers to the distinctive reproductive structure that its flowers possess. Pollination is achieved through the use of the sensitive "trigger", which comprises the male and female reproductive organs fused into a floral column
that snaps forward quickly in response to touch, harmlessly covering the insect in pollen. Most of the approximately 300 species
are only found in Australia
, making it the fifth largest genus in that country. Triggerplants are considered to be protocarnivorous or carnivorous
because the glandular trichome
s that cover the scape
and flower can trap, kill, and digest small insects with protease
enzymes produced by the plant.
of which some are geophytes that utilize bulb
s as their storage organ. The remaining small group of species consists of ephemeral
annuals
.
Members of the genus are most easily identified by their unique floral column
, in which the stamen
and style are fused. The column—also commonly called a "trigger" in this genus—typically resides beneath the plane of the flower. Stylidium flowers are zygomorphic, which means they are only symmetrical in one plane. Flowers usually bloom in the late spring in Australia.
). One typical plant form is a dense rosette
of leaves close to the ground that gives rise to the floral
spike
in the center. Plant forms range from wiry, creeping mats (S. scandens
) to the bushy S. laricifolium.
Flower morphology differs in details, but ascribes to a simple blueprint: four petals, zygomorphic in nature, with the trigger protruding from the "throat" of the flower and resting below the plane of the flower petals. Flower size ranges from many species that have small 0.5 cm (0.2 in) wide flowers to the 2-3 cm (0.7-1.2 in) wide flowers of S. schoenoides. Flower color can also vary from species to species, but most include some combination of white, cream, yellow, or pink. Flowers are usually arranged in a spike or dense raceme
, but there is at least one exception to the rule: S. uniflorum, as its name suggests, produces a single flower per inflorescence
.
Leaf morphology is also very diverse in this large genus. Some leaves are very thin, almost needle-like (S. affine
), while others are short, stubby, and arranged in rosettes (S. pulviniforme). Another group of species, such as S. scandens (climbing triggerplant) form scrambling, tangled mats typically propped up on aerial root
s.
The column typical of the genus Stylidium is sensitive and responds to touch. The change in pressure when a pollinating insect lands on a Stylidium flower causes a physiological change in the column turgor pressure
by way of an action potential
, sending the column quickly flying toward the insect. Upon impact, the insect will be covered in pollen and stunned, but not harmed. Because the column comprises the fused male and female reproductive organs of the flower, the stamen and stigma take turns in dominating the function of the column—the anthers develop first and then are pushed aside by the developing stigma. This delayed development of the stigma prevents self-pollination
and ensures that cross pollination will occur between individuals of a population. Different species have evolved the trigger mechanism in different locations, with some attacking the pollinating insect from above and others from below (a "punch in the gut" to the insect).
The response to touch is very quick in Stylidium species. The column can complete its "attack" on the insect in as little as 15 milliseconds. After firing, the column resets to its original position in anywhere from a few minutes to a half hour, depending on temperature and species-specific qualities. The column is able to fire many times before it no longer responds to stimuli. The response time is highly dependent upon ambient temperature, with lower temperatures relating to slower movement. Stylidium species are typically pollinated by small solitary bees and the nectar-feeding bee flies (Bombyliidae
).
Stylidium species with glandular trichome
s on their sepal
s, leaves, flower parts, or scapes
have been suggested to be protocarnivorous (or paracarnivorous). The tip of the trichome produces a sticky mucilage
—a mixture of sugar polymers and water—that is capable of attracting and suffocating small insects. The ability to trap insects may be a defensive mechanism against damage to flower parts. However, trichomes of S. fimbriatum have been shown to produce digestive enzymes, specifically protease
s, like other carnivorous plant
s. Adding species of Stylidium to the list of plants that engage in carnivory would significantly increase the total number of known carnivorous plants.
The insects captured by the glandular trichomes are too small to serve any role in pollination. It is unclear, however, whether these plants evolved the ability to trap and kill insects as an adaptation to low environmental nutrient availability or simply a defensive mechanism against insects damaging flower parts.
There is also a correlation between location of Stylidium species and proximity of known carnivorous species, like sundew
s (Drosera), bladderwort
s (Utricularia), the Albany pitcher plant
(Cephalotus follicularis), and the rainbow plant
(Byblis). While this alone does not prove that Stylidium species are themselves carnivorous, the hypothesis is that the association arose because Stylidium species and the known carnivorous plants obtain scarce nutrients using the same source, namely captured insects. Preliminary proof is given that the trapping mechanisms of two associated plants are the same (the tentacle
s of Byblis and Drosera), though this may be only a coincidence and further research must be done.
to Australia. In Western Australia
alone, there are more than 150 species, at least 50 of which are in the area immediately around Perth
. There are at least four species of Stylidium that are not confined to the Australian continent: S. tenellum
is found in Myanmar
, Melaka, and Tonkin
; S. kunthii
in Bengal
and Myanmar; S. uliginosum
in Queensland
, Sri Lanka
, and the south coast of China
; and S. alsinoides
in Northeast Australia, Queensland, and the Philippines
. The cladistic group Stylidium contains more than 230 individual species (more than 300 species exist, but many specimens have not yet been formally described), making it the fifth largest genus in Australia.
Stylidium habitat includes grassy plains, open heaths
, rocky slopes, sandplains, forests, and the margins of creeks and water holes. Somes species, such as S. eglandulosum, can even be found in disturbed areas like near roads and under powerlines. Others (i.e. S. coroniforme) are sensitive to disturbance and are considered rare because of their extremely specific habitat.
Even though many species of Stylidium may coexist in the same location, natural hybrids between species have not often been reported. Both natural hybridisation in the field and artificial hybridisation in cultivation are rare. The first natural hybrid, S. petiolare × S. pulchellum, was reported by Sherwin Carlquist
in 1969 between Capel
and Boyanup
in Western Australia.
Discovery and description of new Stylidium species has been occurring since the late 18th century, the first of which was discovered in Botany Bay
in 1770 by Joseph Banks
and Daniel Solander
during their travels in the Pacific with James Cook
aboard the Endeavour
. Seven species were collected by Banks and Solander, some of which were sketched by Sydney Parkinson
on board the Endeavour and were later engraved in preparation for publication in Banks' Florilegium
. Later, in the early 19th century, the French botanist Charles François Antoine Morren
wrote one of the first descriptions of the triggerplant anatomy, illustrated by many botanical artists including Ferdinand Bauer
. Around the same time, British botanist Robert Brown
described (or "authored") several Stylidium species, including S. adnatum
and S. repens
. More species began to be described as more botanists explored Australia more thoroughly.
In 1958, Rica Erickson
wrote Triggerplants, describing habitat, distribution, and plant forms (ephemeral
, creeping, leafy-stemmed, rosette
, tufted, scale-leaved, and tropical). It was Erickson that began placing certain species into these morphologically
-based groups, which may or may not resemble true taxonomic
divergences. It was not until the 1970s and 1980s that research of the trigger physiology
was begun in the lab of Dr. Findlay of Flinders University
. Douglas Darnowski added to the growing library of knowledge on Stylidium when he published his book Triggerplants in 2002, describing an overview of habitat, plant morphology, carnivory, and research done to date. Following its publication, he co-founded the International Triggerplant Society.
As of 2002, only 221 Stylidium species were known. There are now over 300 species, many of which are awaiting formal description.
Most Stylidium species tend to be hardy species and can be easily cultivated in greenhouses or gardens. They are drought resistant, hardy to cold weather, and the species diversity in this genus gives gardeners a wide variety of choices. Most species that are native to Western Australia will be cold hardy to at least -1 to -2°C. The few that can be found all over Australia, like S. graminifolium
, will tolerate a wider range of habitat since their native ranges includes a great diversity of ecoregion
s. Some species of triggerplants are suitable for cultivation outdoors outside of the Australian continent including most of the United Kingdom
and as far north as New York City
or Seattle in the United States
.
Cultivation from seed may be difficult or easy, depending on the species. The more difficult species to grow include the ones that require a period of dormancy or smoke treatment to simulate a bushfire. Stylidium specimens should be grown in a medium that is kept moist and has a relatively low concentration of nutrients. It should also be noted that they appear to be sensitive to disturbance of their root systems. Minimization of such disturbance will likely result in healthier plants.
Dicotyledon
The dicotyledons, also known as dicots, are a group of flowering plants whose seed typically has two embryonic leaves or cotyledons. There are around 199,350 species within this group...
ous plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s that belong to the family Stylidiaceae
Stylidiaceae
The family Stylidiaceae is a taxon of dicotyledonous flowering plants. It consists of five genera with over 240 species, most of which are endemic to Australia and New Zealand. Members of Stylidiaceae are typically grass-like herbs or small shrubs and can be perennials or annuals...
. The genus name Stylidium is derived from the Greek στύλος or stylos (column or pillar), which refers to the distinctive reproductive structure that its flowers possess. Pollination is achieved through the use of the sensitive "trigger", which comprises the male and female reproductive organs fused into a floral column
Column (botany)
The column, or technically the gynostemium, is a reproductive structure that can be found in several plant families: Aristolochiaceae, Orchidaceae, and Stylidiaceae....
that snaps forward quickly in response to touch, harmlessly covering the insect in pollen. Most of the approximately 300 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...
are only found in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, making it the fifth largest genus in that country. Triggerplants are considered to be protocarnivorous or carnivorous
Carnivorous plant
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants appear adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic...
because the glandular trichome
Trichome
Trichomes are fine outgrowths or appendages on plants and certain protists. These are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae.- Algal trichomes :...
s that cover the scape
Scape (botany)
In botany, scapes are leafless flowering stems that rise from the ground. Scapes can have a single flower or many flowers, depending on the species....
and flower can trap, kill, and digest small insects with protease
Protease
A protease is any enzyme that conducts proteolysis, that is, begins protein catabolism by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain forming the protein....
enzymes produced by the plant.
Characteristics
The majority of the Stylidium species are perennial herbsPerennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...
of which some are geophytes that utilize bulb
Bulb
A bulb is a short stem with fleshy leaves or leaf bases. The leaves often function as food storage organs during dormancy.A bulb's leaf bases, known as scales, generally do not support leaves, but contain food reserves to enable the plant to survive adverse conditions. At the center of the bulb is...
s as their storage organ. The remaining small group of species consists of ephemeral
Ephemeral Plant
An ephemeral plant is one marked by short life cycles, usually six to eight weeks. The word ephemeral means transitory or quickly fading. In regards to plants, it refers to several distinct growth strategies...
annuals
Annual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...
.
Members of the genus are most easily identified by their unique floral column
Column (botany)
The column, or technically the gynostemium, is a reproductive structure that can be found in several plant families: Aristolochiaceae, Orchidaceae, and Stylidiaceae....
, in which the stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
and style are fused. The column—also commonly called a "trigger" in this genus—typically resides beneath the plane of the flower. Stylidium flowers are zygomorphic, which means they are only symmetrical in one plane. Flowers usually bloom in the late spring in Australia.
Morphology
Species of the genus Stylidium represent a very diverse selection of plants. Some are only a few centimeters tall, while others can grow to be 1.8 meters (5.9 ft) tall (S. laricifoliumStylidium laricifolium
Stylidium laricifolium is a dicotyledonous plant that belongs to the genus Stylidium . S. laricifolium is endemic to Australia and is found primarily on the east coast of Australia from Queensland through Victoria. It can grow up to 1.5 meters tall in a bushy form. Flowering in the spring, S...
). One typical plant form is a dense rosette
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
of leaves close to the ground that gives rise to the floral
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...
spike
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
in the center. Plant forms range from wiry, creeping mats (S. scandens
Stylidium scandens
Stylidium scandens is a dicotyledonous plant that belongs to the genus Stylidium . S. scandens is endemic to Australia and is found primarily in the southwestern region of Western Australia...
) to the bushy S. laricifolium.
Flower morphology differs in details, but ascribes to a simple blueprint: four petals, zygomorphic in nature, with the trigger protruding from the "throat" of the flower and resting below the plane of the flower petals. Flower size ranges from many species that have small 0.5 cm (0.2 in) wide flowers to the 2-3 cm (0.7-1.2 in) wide flowers of S. schoenoides. Flower color can also vary from species to species, but most include some combination of white, cream, yellow, or pink. Flowers are usually arranged in a spike or dense raceme
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
, but there is at least one exception to the rule: S. uniflorum, as its name suggests, produces a single flower per 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...
.
Leaf morphology is also very diverse in this large genus. Some leaves are very thin, almost needle-like (S. affine
Stylidium affine
Stylidium affine is a species in the genus Stylidium that is endemic to Western Australia.- Description :Stylidium affine is a perennial plant that possesses long erect or recurved lanceolate leaves...
), while others are short, stubby, and arranged in rosettes (S. pulviniforme). Another group of species, such as S. scandens (climbing triggerplant) form scrambling, tangled mats typically propped up on aerial root
Aerial root
Aerial roots are roots above the ground. They are almost always adventitious. They are found in diverse plant species, including epiphytes such as orchids, tropical coastal swamp trees such as mangroves, the resourceful banyan trees, the warm-temperate rainforest rātā and pōhutukawa Aerial roots...
s.
Pollination mechanism
Turgor pressure
Turgor Pressure or turgidity is the main pressure of the cell contents against the cell wall in plant cells and bacteria cells, determined by the water content of the vacuole, resulting from osmotic pressure, i.e...
by way of an action potential
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...
, sending the column quickly flying toward the insect. Upon impact, the insect will be covered in pollen and stunned, but not harmed. Because the column comprises the fused male and female reproductive organs of the flower, the stamen and stigma take turns in dominating the function of the column—the anthers develop first and then are pushed aside by the developing stigma. This delayed development of the stigma prevents self-pollination
Self-pollination
Self-pollination is a form of pollination that can occur when a flower has both stamen and a carpel in which the cultivar or species is self fertile and the stamens and the sticky stigma of the carpel contact each other in order to accomplish pollination...
and ensures that cross pollination will occur between individuals of a population. Different species have evolved the trigger mechanism in different locations, with some attacking the pollinating insect from above and others from below (a "punch in the gut" to the insect).
The response to touch is very quick in Stylidium species. The column can complete its "attack" on the insect in as little as 15 milliseconds. After firing, the column resets to its original position in anywhere from a few minutes to a half hour, depending on temperature and species-specific qualities. The column is able to fire many times before it no longer responds to stimuli. The response time is highly dependent upon ambient temperature, with lower temperatures relating to slower movement. Stylidium species are typically pollinated by small solitary bees and the nectar-feeding bee flies (Bombyliidae
Bombyliidae
Bombyliidae is a large family of flies with hundreds of genera, although their life cycles are not well known. Adults generally feed on nectar and pollen, thus are pollinators of flowers. They superficially resemble bees, thus are commonly called bee flies, and this may offer the adults some...
).
Carnivory
Trichome
Trichomes are fine outgrowths or appendages on plants and certain protists. These are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae.- Algal trichomes :...
s on 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, leaves, flower parts, or scapes
Scape (botany)
In botany, scapes are leafless flowering stems that rise from the ground. Scapes can have a single flower or many flowers, depending on the species....
have been suggested to be protocarnivorous (or paracarnivorous). The tip of the trichome produces a sticky mucilage
Mucilage
Mucilage is a thick, gluey substance produced by most plants and some microorganisms. It is a polar glycoprotein and an exopolysaccharide.It occurs in various parts of nearly all classes of plant, usually in relatively small percentages, and is frequently associated with other substances, such as...
—a mixture of sugar polymers and water—that is capable of attracting and suffocating small insects. The ability to trap insects may be a defensive mechanism against damage to flower parts. However, trichomes of S. fimbriatum have been shown to produce digestive enzymes, specifically protease
Protease
A protease is any enzyme that conducts proteolysis, that is, begins protein catabolism by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain forming the protein....
s, like other carnivorous plant
Carnivorous plant
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants appear adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic...
s. Adding species of Stylidium to the list of plants that engage in carnivory would significantly increase the total number of known carnivorous plants.
The insects captured by the glandular trichomes are too small to serve any role in pollination. It is unclear, however, whether these plants evolved the ability to trap and kill insects as an adaptation to low environmental nutrient availability or simply a defensive mechanism against insects damaging flower parts.
There is also a correlation between location of Stylidium species and proximity of known carnivorous species, like sundew
Sundew
Drosera, commonly known as the sundews, comprise one of the largest genera of carnivorous plants, with at least 194 species. These members of the family Droseraceae lure, capture, and digest insects using stalked mucilaginous glands covering their leaf surface. The insects are used to supplement...
s (Drosera), bladderwort
Bladderwort
Utricularia, commonly and collectively called the bladderworts, is a genus of carnivorous plants consisting of approximately 233 species . They occur in fresh water and wet soil as terrestrial or aquatic species across every continent except Antarctica...
s (Utricularia), the Albany pitcher plant
Cephalotus
Cephalotus is a genus which contains one species, Cephalotus follicularis, a small carnivorous pitcher plant. The pit-fall traps of the modified leaves have inspired the common names for this plant, which include Albany Pitcher Plant, Western Australian Pitcher Plant, fly-catcher plant or...
(Cephalotus follicularis), and the rainbow plant
Byblis (plant)
Byblis is a small genus of carnivorous plants, sometimes termed the rainbow plants for the attractive appearance of their mucilage-covered leaves in bright sunshine. Native to western Australia, it is the only genus in the family Byblidaceae. The first species in the genus was described by the...
(Byblis). While this alone does not prove that Stylidium species are themselves carnivorous, the hypothesis is that the association arose because Stylidium species and the known carnivorous plants obtain scarce nutrients using the same source, namely captured insects. Preliminary proof is given that the trapping mechanisms of two associated plants are the same (the tentacle
Tentacle
A tentacle or bothrium is one of usually two or more elongated flexible organs present in animals, especially invertebrates. The term may also refer to the hairs of the leaves of some insectivorous plants. Usually, tentacles are used for feeding, feeling and grasping. Anatomically, they work like...
s of Byblis and Drosera), though this may be only a coincidence and further research must be done.
Distribution and habitat
Most Stylidium species are endemicEndemic (ecology)
Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
to Australia. In Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
alone, there are more than 150 species, at least 50 of which are in the area immediately around Perth
Perth, Western Australia
Perth is the capital and largest city of the Australian state of Western Australia and the fourth most populous city in Australia. The Perth metropolitan area has an estimated population of almost 1,700,000....
. There are at least four species of Stylidium that are not confined to the Australian continent: S. tenellum
Stylidium tenellum
Stylidium tenellum is a dicotyledonous plant that belongs to the genus Stylidium . It is an annual plant that grows from 5 to 27 cm tall. The obovate or elliptical leaves, about 6-14 per plant, are scattered along the elongate, glabrous stem and are generally 3.5-8.5 mm long and...
is found in Myanmar
Myanmar
Burma , officially the Republic of the Union of Myanmar , is a country in Southeast Asia. Burma is bordered by China on the northeast, Laos on the east, Thailand on the southeast, Bangladesh on the west, India on the northwest, the Bay of Bengal to the southwest, and the Andaman Sea on the south....
, Melaka, and 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"...
; S. kunthii
Stylidium kunthii
Stylidium kunthii is a dicotyledonous plant that belongs to the genus Stylidium and is one of the few species in the genus that is not native to Australia. It is an erect annual plant that grows from 8 to 20 cm tall. Obovate, orbicular, or obleanceolate leaves, about 5-15 per plant, form...
in 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...
and Myanmar; S. uliginosum
Stylidium uliginosum
Stylidium uliginosum is a dicotyledonous plant that belongs to the genus Stylidium and is one of the few species in the genus that is not native to Australia. It is an erect annual plant that grows from 4 to 15 cm tall. Obovate or elliptical leaves, about 7-16 per plant, form basal rosettes...
in Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
, Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
, and the south coast of 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 S. alsinoides
Stylidium alsinoides
Stylidium alsinoides is a dicotyledonous plant that belongs to the genus Stylidium . It is an erect annual plant that grows from 18 to 30 cm tall. Obovate or elliptical leaves, about 20–100 per plant, are scattered along the elongate, glabrous stems. The leaves are generally...
in Northeast Australia, Queensland, and the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
. The cladistic group Stylidium contains more than 230 individual species (more than 300 species exist, but many specimens have not yet been formally described), making it the fifth largest genus in Australia.
Stylidium habitat includes grassy plains, open heaths
Heath (habitat)
A heath or heathland is a dwarf-shrub habitat found on mainly low quality acidic soils, characterised by open, low growing woody vegetation, often dominated by plants of the Ericaceae. There are some clear differences between heath and moorland...
, rocky slopes, sandplains, forests, and the margins of creeks and water holes. Somes species, such as S. eglandulosum, can even be found in disturbed areas like near roads and under powerlines. Others (i.e. S. coroniforme) are sensitive to disturbance and are considered rare because of their extremely specific habitat.
Even though many species of Stylidium may coexist in the same location, natural hybrids between species have not often been reported. Both natural hybridisation in the field and artificial hybridisation in cultivation are rare. The first natural hybrid, S. petiolare × S. pulchellum, was reported by Sherwin Carlquist
Sherwin Carlquist
Sherwin Carlquist is an American botanist and photographer. He received his undergraduate degree from the University of California, Berkeley in 1952 and a Ph.D. in botany in 1956, also at Berkeley. Carlquist did a postdoctoral study at Harvard University from 1955 to 1956. After his postdoctoral...
in 1969 between Capel
Capel, Western Australia
Capel is a town in the South West region of Western Australia, located 212 kilometres south of Perth and midway between Bunbury and Busselton....
and Boyanup
Boyanup, Western Australia
Boyanup is a town located on the South Western Highway in the South West agricultural region, 195 km south of Perth and 18 km south-east of Bunbury, Western Australia....
in Western Australia.
Botanical history
Botany Bay
Botany Bay is a bay in Sydney, New South Wales, a few kilometres south of the Sydney central business district. The Cooks River and the Georges River are the two major tributaries that flow into the bay...
in 1770 by Joseph Banks
Joseph Banks
Sir Joseph Banks, 1st Baronet, GCB, PRS was an English naturalist, botanist and patron of the natural sciences. He took part in Captain James Cook's first great voyage . Banks is credited with the introduction to the Western world of eucalyptus, acacia, mimosa and the genus named after him,...
and Daniel Solander
Daniel Solander
Daniel Carlsson Solander or Daniel Charles Solander was a Swedish naturalist and an apostle of Carl Linnaeus. Solander was the first university educated scientist to set foot on Australian soil.-Biography:...
during their travels in the Pacific with James Cook
James Cook
Captain James Cook, FRS, RN was a British explorer, navigator and cartographer who ultimately rose to the rank of captain in the Royal Navy...
aboard the Endeavour
HM Bark Endeavour
HMS Endeavour, also known as HM Bark Endeavour, was a British Royal Navy research vessel commanded by Lieutenant James Cook on his first voyage of discovery, to Australia and New Zealand from 1769 to 1771....
. Seven species were collected by Banks and Solander, some of which were sketched by Sydney Parkinson
Sydney Parkinson
Sydney Parkinson was a Scottish Quaker, botanical illustrator and natural history artist.Parkinson was employed by Joseph Banks to travel with him on James Cook's first voyage to the Pacific in 1768. Parkinson made nearly a thousand drawings of plants and animals collected by Banks and Daniel...
on board the Endeavour and were later engraved in preparation for publication in Banks' Florilegium
Banks' Florilegium
Banks' Florilegium is a collection of copperplate engravings of plants collected by Sir Joseph Banks and Daniel Solander while they accompanied Captain James Cook on his voyage around the world between 1768 and 1771...
. Later, in the early 19th century, the French botanist Charles François Antoine Morren
Charles François Antoine Morren
Charles François Antoine Morren , was a Belgian botanist and horticulturist, and Director of the Jardin botanique de l’Université de Liège....
wrote one of the first descriptions of the triggerplant anatomy, illustrated by many botanical artists including Ferdinand Bauer
Ferdinand Bauer
Ferdinand Lucas Bauer was an Austrian botanical illustrator who travelled on Matthew Flinders' expedition to Australia.-Biography:...
. Around the same time, British botanist 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...
described (or "authored") several Stylidium species, including S. adnatum
Stylidium adnatum
Stylidium adnatum is a dicotyledonous plant that belongs to the genus Stylidium . S. adnatum is endemic to Australia and is found primarily in the southwest region of Western Australia....
and S. repens
Stylidium repens
Stylidium repens is a dicotyledonous plant that belongs to the genus Stylidium . S. repens is endemic to Australia and is found primarily in southwest Western Australia. This species is a creeping or scrambling triggerplant, which can spread over large areas as a tangled mat of stems and aerial...
. More species began to be described as more botanists explored Australia more thoroughly.
In 1958, Rica Erickson
Rica Erickson
Frederica Lucy "Rica" Erickson AM, née Sandilands, was an Australian naturalist, botanical artist, historian, author and teacher. Without any formal scientific training, she wrote extensively on botany and birds, as well as genealogy and general history...
wrote Triggerplants, describing habitat, distribution, and plant forms (ephemeral
Ephemeral
Ephemeral things are transitory, existing only briefly. Typically the term is used to describe objects found in nature, although it can describe a wide range of things....
, creeping, leafy-stemmed, rosette
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
, tufted, scale-leaved, and tropical). It was Erickson that began placing certain species into these morphologically
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
-based groups, which may or may not resemble true taxonomic
Plant taxonomy
Plant taxonomy is the science that finds, describes, classifies, identifies, and names plants. It thus is one of the main branches of taxonomy.Plant taxonomy is closely allied to plant systematics, and there is no sharp boundary between the two...
divergences. It was not until the 1970s and 1980s that research of the trigger physiology
Plant physiology
Plant physiology is a subdiscipline of botany concerned with the functioning, or physiology, of plants. Closely related fields include plant morphology , plant ecology , phytochemistry , cell biology, and molecular biology.Fundamental processes such as photosynthesis, respiration, plant nutrition,...
was begun in the lab of Dr. Findlay of Flinders University
Flinders University
Flinders University, , is a public university in Adelaide, South Australia. Founded in 1966, it was named in honour of navigator Matthew Flinders, who explored and surveyed the South Australian coastline in the early 19th century.The university has established a reputation as a leading research...
. Douglas Darnowski added to the growing library of knowledge on Stylidium when he published his book Triggerplants in 2002, describing an overview of habitat, plant morphology, carnivory, and research done to date. Following its publication, he co-founded the International Triggerplant Society.
As of 2002, only 221 Stylidium species were known. There are now over 300 species, many of which are awaiting formal description.
Cultivation
Stylidium graminifolium
Stylidium graminifolium, the grass triggerplant, is a dicotyledonous plant that belongs to the genus Stylidium . This species used to belong to the Stylidium graminifolium complex, but the name was conserved for this single species when two others were split from the complex and introduced as new...
, will tolerate a wider range of habitat since their native ranges includes a great diversity of ecoregion
Ecoregion
An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...
s. Some species of triggerplants are suitable for cultivation outdoors outside of the Australian continent including most of the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
and as far north as New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
or Seattle in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Cultivation from seed may be difficult or easy, depending on the species. The more difficult species to grow include the ones that require a period of dormancy or smoke treatment to simulate a bushfire. Stylidium specimens should be grown in a medium that is kept moist and has a relatively low concentration of nutrients. It should also be noted that they appear to be sensitive to disturbance of their root systems. Minimization of such disturbance will likely result in healthier plants.
External links
- Australian Department of the Environment and Heritage document on the "Wongan Hills Triggerplant (Stylidium coroniforme) Interim Recovery Plan 2003-2008". (PDF version)
- FloraBase (Western Australia's flora database) entry on Stylidium.
- Association of Societies for Growing Australian Plants (ASGAP) information on Stylidium laricifolium and Stylidium graminifolium.
- International Plant Names IndexIPNIThe International Plant Names Index is a database of botanical names. It indexes names of seed plants, ferns and "fern allies". Coverage is best at the rank of species and genus...
(IPNI) list of published Stylidium species names. - Photos and animations of triggerplants, featuring several species.
- The International Triggerplant Society.