Melanthieae | |
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Veratrum album | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Order: | Liliales |
Family: | Melanthiaceae |
Tribe: | Melanthieae |
Synonyms | |
Veratreae T.Nees & C.H.Eberm. ex Endl. |
Melanthieae is a tribe of flowering plants within the family Melanthiaceae. Molecular phylogenetic studies in the 21st century have resulted in a large-scale reassignment of many of its species to different genera; in particular the genus Zigadenus (deathcamases) has been restricted to a single species, Zigadenus glaberrimus . Plants contain alkaloids, making them unpalatable to grazing animals; many are very poisonous to both animals and humans.
Like the family as a whole, members of the tribe are "lilioid monocots", i.e. their flowers superficially resemble those of the genus Lilium, with six tepals not differentiated into sepals and petals. As with other lilioid monocots, they were previously included in a broadly defined family Liliaceae. They are found mainly in woodland or alpine habitats in the temperate regions of the Northern Hemisphere (North America, Central America, and Asia), with one species found in South America. They are perennials, growing from a bulb or rhizome (or both). [1] Plants have relatively long leaves, both at the base of the plant and along the flowering stems; many have off-white flowers, tending towards green or purple.
The tribe has some distinctive features within the family Melanthiaceae, including nectaries on the tepals (whose number and position is a useful identifying character for some genera); the unusual way in which the anthers open (dehisce) to release pollen; and the possession of a particular class of alkaloids (veratrum alkaloids). [1] Because of these alkaloids, all members of the tribe are at least unpalatable to livestock, and some are seriously toxic to both animals and humans. Many species have common names including the words "death camas", because of their toxicity and their superficial similarity to the unrelated genus Camassia , species of which are known as "camas".
The species making up the tribe Melanthieae have been considered to form a "natural group" for a long time; the name "Melanthieae" was first used by August Grisebach in 1846. [2] Other names which have been used with more or less the same circumscription include Veratreae and Melanthiaceae sensu stricto. [1]
The main genera included in the tribe before the start of the 21st century were Schoenocaulon , Stenanthium , Veratrum , Melanthium (often included in Veratrum) and Zigadenus s.l. The last genus contained about 20 species when broadly defined and lacked very distinctive morphological features. Various genera were constructed between 1837 and 1903 to divide up Zigadenus, including Amianthium (Gray, 1837), Anticlea (Kunth, 1843) and Toxicoscordion (Rydberg, 1903). Only the first of these gained broad acceptance in the 20th century (e.g. the Flora of North America recognizes only Amianthium and Zigadenus [3] ). A study in 2001 based on both nuclear and plastid gene sequences led to the conclusion that the broadly defined Zigadenus was polyphyletic; in particular the genera Schoenocaulon and Veratrum-Melanthium were nested inside it. [1] Monophyletic groups could be produced by splitting Zigadenus into five genera (assuming Amianthium to have been included): Amianthium, Anticlea, Stenanthium, and Toxicoscordion, leaving only Zigadenus glaberrimus in Zigadenus. Although the reorganization was done primarily on the basis of molecular grounds, it is supported by morphological and distributional considerations. [1] [4] The cladogram below shows phylogenetic relationships in the Tribe Melanthieae; shaded names represent nodes which contain species formerly placed in the broadly defined Zigadenus. [1]
Tribe Melanthieae |
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The distributions and some key features of the genera into which Zigadenus is divided are: [1]
Around twenty species were included in the genus Zigadenus as it was previously circumscribed. Zigadenus glaberrimus , sandbog deathcamas, is the only species remaining. Zigadenus species which have been transferred to other genera are listed below under their new name. [4]
In addition, three species have been transferred from Stenanthium to Anticlea. [5]
Amianthium consists of a single species, A. muscitotoxum , known as flypoison. It is found in eastern North America. It grows from a bulb and has a dense oval-shaped inflorescence. Individual flowers start off white and develop red-green shades with age. All parts of the plant are poisonous; two unique alkaloids, jervine and amianthine, contribute to its toxicity. [6]
As currently circumscribed, Anticlea consists of about 11 species, found in Asia, North America and Central America down to Guatemala. [7] Anticlea elegans (the mountain deathcamas) is one of the best known. Like other species in the genus, it grows from bulbs and has flowers with relatively narrow tepals, in this case coloured white to green. [4] [8]
Melanthium is sometimes included in the closely related genus Veratrum . As of April 2012 [update] , the World Checklist of Selected Plant Families recognizes four species, found in the central and eastern United States. [9] Their flowers differ from Veratrum by being arranged in more open and delicate-looking inflorescences and by having tepals which narrow at the base. [10]
Schoenocaulon is a genus of around 25 species. The precise number is unclear; two species were only discovered in 2008, and many occur only in remote regions of Mexico, where their montane forest habitat is under threat. The centre of diversity is in Mexico. They are also found in Central America, with a few species extending into South America, and in the United States, along the eastern part of the border with Mexico and in Florida. They grow from a bulb with a fibrous coat and have a long narrow spike-like inflorescence made up of very small flowers with long protruding stamens. [11]
As of April 2012 [update] , Stenanthium consists of three [12] or four species (depending on whether S. leimanthoides is recognized) found in the south eastern United States. [1] Like the other species, Stenanthium gramineum (feather bells) grows from a slender bulb, and has inflorescences with a complex branching structure in which individual flowers have narrow tapering tepals. [13]
Eight species are included in the genus Toxicoscordion , [12] which is found in western North America. The well-known poisonous species formerly placed in Zigadenus, the "deathcamas", are now included in Toxicoscordion. Plants grow from an ovoid bulb and have tepals which are narrowed at their bases to form a "claw". [4] Toxicoscordion venenosum, the meadow deathcamas, is one of the more widely distributed species. Its flowers are white to cream in colour and grow in pointed clusters. [14]
Veratrum is found throughout temperate regions of the Northern Hemisphere. The genus has possibly as many as 40 species, [15] depending on how finely some of the widely distributed species are divided and whether the closely related genus Melanthium is included or not. Plants grow from a combination of short rhizomes and bulbs. They generally have quite large leaves and inflorescences in which individual flowers vary in colour from white to green, yellow or purple. They contain a variety of alkaloids which make them poisonous, although some have medical uses. Some species are cultivated for their form as well as their flowers. [16]
The genus Zigadenus now contains only a single species Z. glaberrimus , the sandbog deathcamas. Found in the south eastern United States, it grows from thick rhizomes rather than bulbs. The flowers are grouped into a loose inflorescence and are white to cream in colour. [17]
Melanthiaceae, also called the bunchflower family, is a family of flowering herbaceous perennial plants native to the Northern Hemisphere. Along with many other lilioid monocots, early authors considered members of this family to belong to the family Liliaceae, in part because both their sepals and petals closely resemble each other and are often large and showy like those of lilies, while some more recent taxonomists have placed them in a family Trilliaceae. The most authoritative modern treatment, however, the APG III system of 2009, places the family in the order Liliales, in the clade monocots. Circumscribed in this way, the family includes up to 17 genera.
Toxicoscordion fremontii, known as the common star lily or Frémont's deathcamas or star zigadene, is an attractive wildflower found on grassy or woody slopes, or rocky outcrops, in many lower-lying regions of California, southwestern Oregon, and northern Baja California.
Amianthium is a North American genus of perennial plants growing from bulbs. It contains the single known species Amianthium muscitoxicum, known in English as fly poison from a literal translation of the Latin epithet muscitoxicum, and is noted for its pretty flowers and its toxic alkaloid content. While all parts of the plant are poisonous, the bulb is particularly toxic. The scientific epithet was given to it by Thomas Walter when he published his Flora Caroliniana in 1788.
Toxicoscordion venenosum, with the common names death camas and meadow death camas, is a species of flowering plant in the genus Toxicoscordion, of the Melanthiaceae family. It is native to western North America from New Mexico to Saskatchewan and west to the Pacific Ocean.
Deathcamas or death camas refers to several species of flowering plant in the tribe Melanthieae. The name alludes to the great similarity of appearance between these toxic plants, which were formerly classified together in the genus Zigadenus, and the edible camases (Camassia), with which they also often share habitat. Other common names for these plants include deadly zigadene, hog potato and mystery-grass.
Toxicoscordion micranthum, the smallflower deathcamas, is a flowering plant in the genus Toxicoscordion. It is native to Oregon and California, primarily in the Coast Ranges from Douglas County to Napa and Sonoma Counties, with isolated populations in Lassen, Plumas, Santa Clara, and San Benito Counties. It is a member of the serpentine soils flora.
Schoenocaulon is a North American genus of perennial herbaceous flowering plants, ranging from the southern United States to Peru. It is a member of the Melanthiaceae, according to the APG III classification system, and is placed in the tribe Melanthieae. Unlike other genera in the tribe, the flowers are arranged in a spike; depending on the species the flower stalks for each flower are either very short or completely absent. Feathershank is a common name, the medicinally used S. officinale is called Sabadilla.
Melanthium is a genus of herbaceous perennial plants native to North America. They are closely related to Veratrum, and in fact are included in that genus by some authors. The distinction between Melanthium and Veratrum is based on various morphological traits, but it is not yet clear where the line is best drawn.
Anticlea is a genus of flowering plants in the family Melanthiaceae, tribe Melanthieae. Molecular phylogenetic studies in the 21st century have resulted in number of changes to placements within this tribe. Anticlea was long submerged into the genus Zigadenus; however its separate position has been confirmed. Some species were also moved from Stenanthium into Anticlea. Members of Anticlea may also be distinguished from other members of the former genus Zigadenus, the deathcamases, by the presence of narrow tepals with a single, conspicuous, bilobed gland. It also has a wider distribution, occurring in Asia and much of North and Central America, ranging south to Guatemala.
Toxicoscordion is a genus of flowering plants in the family Melanthiaceae, tribe Melanthieae, first described as a genus in 1903. The genus is mainly distributed in the midwestern United States and western North America, with some species in western Canada and northern Mexico.
Stenanthium is a North American genus of flowering plants in the tribe Melanthieae of the family Melanthiaceae.
Zigadenus is a genus of flowering plants now containing only one species, Zigadenus glaberrimus, the sandbog death camas, found in the southeastern United States from Mississippi to Virginia. Around 20 species were formerly included in the genus, but have now been moved to other genera.
Toxicoscordion brevibracteatum is a species of flowering plant known by the common name desert deathcamas. It is native to Baja California, Sonora, and California, where it grows in sandy desert habitat among creosote and Joshua trees.
Toxicoscordion paniculatum is a species of flowering plant known by the common names foothill deathcamas, panicled death-camas, and sand-corn. It is widely distributed across much of the western United States, especially in the mountains and deserts of the Great Basin region west of the Rocky Mountains. It grows in many types of habitat, including sagebrush plateau, grasslands, forests, and woodlands, etc.
Veratrum hybridum is a species of flowering plant in the Melanthiaceae known by the common names slender bunchflower and crisped bunchflower. Many publications use the synonyms Melanthium latifolium and Veratrum latifolium, but the "hybridum" epithet is 9 years older than the "latifolium," so Veratrum hybridum is now the accepted name.
Toxicoscordion nuttallii is a species of poisonous plant native to the south-central part of the United States.
Stenanthium densum is a poisonous but spectacular monocot wildflower native to pine barrens of the eastern United States. It is known variously as Osceola's plume, crowpoison, or black snakeroot. Stenanthium leimanthoides is either treated as a synonym of this species or as a separate species. It is native to the southernmost Gulf Coast, from eastern Louisiana east, down through most of Florida, and to the easternmost Atlantic Coast north to Rhode Island, seldom far from the coast.
Melanthium woodii, common names Wood's bunchflower or Ozark bunch-flower, is a species formerly known as Veratrum woodii. It is native to the central and southeastern parts of the United States, from Arkansas, Florida, Georgia, Illinois, Indiana, Iowa, Kentucky, Missouri, North Carolina, Ohio, Oklahoma and Tennessee. It can be found in forested areas at elevations less than 800 m.
Toxicoscordion fontanum,, common name small-flower death camas, is a rare plant species known only from serpentine marshes in California. It is found primarily in the Coast Ranges from Mendocino County to San Luis Obispo County, with an additional report of an isolated population in the Sierra Nevada foothills in Kern County east of Bakersfield.
Zygacine is a steroidal alkaloid of the genera Toxicoscordion, Zigadenus, Stenanthium and Anticlea of the family Melanthiaceae. These plants are commonly known and generally referred to as death camas. Death camas is prevalent throughout North America and is frequently the source of poisoning for outdoor enthusiasts and livestock due to its resemblance to other edible plants such as the wild onion. Despite this resemblance, the death camas plant lacks the distinct onion odor and is bitter to taste.