Asarina | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Lamiales |
Family: | Plantaginaceae |
Tribe: | Antirrhineae |
Genus: | Asarina Mill. (1757) |
Species: | A. procumbens |
Binomial name | |
Asarina procumbens Mill. (1768) | |
Synonyms [1] | |
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Asarina is a flowering plant genus of only one species, Asarina procumbens Mill. [2] the trailing snapdragon, [3] which is native to France and Spain and introduced in Germany, Switzerland, Austria and Hungary. [4] Originally placed in the Scrophulariaceae (figwort family), the genus has more recently been moved to the Plantaginaceae (plantain family). [5] Species from North America formerly placed in the genus Asarina are now placed in Holmgrenanthe , Lophospermum , Mabrya and Maurandya , [6] as well as Neogaerrhinum . Asarina is now regarded as exclusively an Old World genus. [7] [8]
The single remaining species of the now monotypic genus, A. procumbens is a foetid, strongly pubescent, viscid subshrub of trailing/mat-forming habit reaching a height of only 10-20cm. The somewhat woody main stems give rise to lax creeping/cascading stems bearing opposite, long-petioled, hairy, lobed, reniform-to-cordate leaves with crenate and often red-tinged margins. Flowers solitary or in short racemes of only two or three, fragrant, bumblebee-pollinated, borne in the leaf axils. Corolla cream-coloured, somewhat resembling that of Antirrhinum, the tube bearing faint violet striations, the upper part divided into two keel-like lips, the lower bearing paired inflated lobes, concealing the corolla tube, with a three-lobed margin; pistil violet, persistent, stamens four. Base of corolla bearing (starting behind inflated lobes and extending into corolla throat) a dense mat or beard of deep yellow trichomes. Calyx tubular, five-toothed, densely hairy. Peduncle narrow where joined to stem, thickening greatly to junction with fruiting calyx, reflexed so as to lie parallel to capsule. Fruit a dry capsule, glabrous, subglobose, shorter than the calyx and dehiscing at the apex by two openings separating three valves, the central valve bearing the persistent withered pistil. Seeds small, brownish-buff, roughly conical, testa finely incised with deep sinuous furrows. Seed distribution is by epizoochory, the sticky fruiting calyces becoming attached to the fur of mammals or the feathers of birds, allowing the small seeds to trickle from the dry, open capsules. [9]
A. procumbens is a semi-evergreen alpine chasmophyte, favouring partial shade, its preferred habitat being crevices in silica-rich, non-sedimentary rocks. This type of habitat - "Mediterranean siliceous inland cliff" - is designated by endangered habitat code H3.1d by the European Red List of Habitats. The term siliceous cliffs (in this context) refers to those which are composed chiefly of quartz-rich rocks (making them of an acidic character) of either igneous type, such as granite, diorite and andesite, or metamorphic type, such as gneiss, slate, schist and quartzite. Low-altitude cliffs of this type - as favoured by A. procumbens - are more affected by human disturbances than high mountain cliffs, as the latter often occur within nature reserves and other protected areas. Cliffs at low altitudes, by contrast, are susceptible to a wide variety of threats including the shoring-up of cliffs over roads and railway lines, sport and leisure activities -particularly rock-climbing - and, at lower elevations, mining, quarrying and invasive/alien plants. [10] In the French part of its range A. procumbens is seldom to be found growing at altitudes below 400m, with an upper limit of some 1800m. [9] [11]
A. procumbens is not a common species in the French part of its range, even having protected status in the Auvergne region. Its strongholds in France comprise the Pyrénées-Orientales (taking in the Franco-Catalan area of historic Rousillon) and the Massif central - notably the Cévennes. In Spain the plant is native to the Pyrenean region, but may be found naturalised elsewhere. [9]
A. procumbens grows best in somewhat dry partial shade. Soil: well-drained, sandy/gravelly, humus-rich, moderately moist: dislikes excessive winter wetness. Blooms most profusely in climates in which summers are not excessively hot. Pollinated by bumblebees. Plant is evergreen in mild climates, although may be killed outright by heavy frost, in which case may be propagated afresh: self-seeds readily. Uses: trailing alpine or ground cover. Thrives and increases rapidly as a container plant. Not usually invasive in gardens, though one report of aggressive growth from southeastern U.S.A. [12] Pruning: not usually needed, though may be cut back in autumn if foliage is spent or untidy. Hardiness zone: U.K. H3. USDA zones 8,9 & 10. [13] [14] [12]
A. procumbens has escaped from cultivation to become an attractive (and not, at present, invasive) weed in the inner suburbs of the Australian city of Melbourne, managing to grow in such harsh urban habitats as cracks in the mortar of brick walls and kerbstones and the juncture between brick walls and tarmac. Such weedy populations are short-lived and do not produce abundant seed, because of the current absence of bumblebees from the Australian insect fauna (in its native habitats in France and Spain Asarina is buzz-pollinated by bumblebee species): the Australian native bees and introduced honeybees of Melbourne find Asarina flowers resistant to their attempts at pollination. This situation is, however, likely to change for the worse, should bumblebee species already present in neighbouring Tasmania cross the Bass Strait, in which case bumblebee-pollinated species - such as Asarina - hitherto considered "safe" (i.e. non-invasive) garden plants in the state of Victoria - would rapidly become invasive due to increased production of viable seed. Michael Cook hypothesises that the Asarina colonies currently observable in suburban Melbourne may be more the result of wind-blown drift of packaged seed sown by local gardeners than of the setting of seed by garden plants and plants maintaining a foothold as weeds. [15]
At one time placed in Asarina: [6]
Rhodochiton is a genus of flowering plants within the family Plantaginaceae, native to southern Mexico and neighbouring Guatemala. They climb by means of twining leaf stalks. One of the three species, Rhodochiton atrosanguineus, the purple bell vine, is grown as an ornamental plant. All three species are sometimes included in Lophospermum.
Lophospermum is a genus of herbaceous perennial climbers or scramblers, native to mountainous regions of Mexico and Guatemala. Those that climb use twining leaf stalks. Their flowers are tubular, in shades of red, violet and purple, the larger flowers being pollinated by hummingbirds. Now placed in the greatly expanded family Plantaginaceae, the genus was traditionally placed in the Scrophulariaceae. The close relationship with some other genera, particularly Maurandya and Rhodochiton, has led to confusion over the names of some species.
Maurandya is a genus of flowering plants in the family Plantaginaceae, native to Mexico and the south west United States. They sprawl or climb by means of twining leaf stalks. One of the four species, Maurandya barclayana, is widely cultivated as an ornamental plant.
Mimulus alatus, the sharpwing monkeyflower, is an herbaceous eudicot perennial that has no floral scent. It is native to North America and its blooming season is from June to September. The flowering plant has green foliage and blue to violet flowers. It has a short life span compared to most other plants and a rapid growth rate. Like other monkey-flowers of the genus Mimulus, M. alatus grows best in wet to moist conditions and has a bilabiate corolla, meaning it is two-lipped. The arrangement of the upper and lower lip petals suggests a monkey’s face. The winged stems together with the monkey face give the plant its common name.
Holmgrenanthe petrophila is a rare perennial desert plant in the plantain family (Plantaginaceae), and the sole species of the genus Holmgrenanthe. It forms low mats of branched stems growing from a woody base. The leaves have small spines along their edges. The solitary yellow flowers are tubular with five free lobes at the end, the upper two pointing backwards, the lower three projecting forwards. The species is known only from about ten locations, most in the Titus Canyon and the adjacent Fall Canyon, all within the Californian section of Death Valley National Park. It grows in limestone crevices on the canyon walls, often on the north face.
Lophospermum erubescens, known as Mexican twist or creeping gloxinia, is a climbing or sprawling herbaceous perennial plant, native to the Sierra Madre Oriental mountains of Mexico, where it is found along forest margins or canyon walls. It climbs by means of twining leaf stalks. Wild plants have pink and white tubular flowers, although other colours are found in cultivation. It has been cultivated as an ornamental plant since at least 1830. Although not frost-hardy, it will survive if its base and roots are protected from freezing in the winter. It has escaped from cultivation and become naturalized in tropical and subtropical areas of the world.
Lophospermum scandens is a scambling or climbing herbaceous perennial native to south central Mexico, with red-violet and white tubular flowers and toothed heart-shaped leaves. It grows at elevations between 1,400 and 2,400 m in dry habitats, including deciduous oak forests and recent lava flows. The long-tubed flowers are pollinated by hummingbirds. It has been used in gardens as an ornamental plant since the mid-19th century. Its roots require protection from frost in regions where this occurs in the winter. Hybrids of L. scandens are also grown.
Rhodochiton atrosanguineus is a herbaceous perennial vine native to Mexico. It has been cultivated as an ornamental plant since at least 1836.
Mabrya is a genus of flowering plants in the plantain family, Plantaginaceae. It consists of herbaceous perennials with brittle upright or drooping stems, found in dry areas of Mexico and the southern United States.
The Antirrhineae are one of the 12 tribes of the family Plantaginaceae. It contains the toadflax relatives, such as snapdragons.
Maurandya scandens, also known as trailing snapdragon and snapdragon vine, is a climbing herbaceous perennial native to Mexico, with snapdragon-like flowers and untoothed leaves. It is grown as an ornamental plant in many parts of the world, and has commonly escaped from cultivation to become naturalized. Other names for this plant include creeping snapdragon, vining snapdragon, creeping gloxinia and chickabiddy.
Maurandella antirrhiniflora, known as roving sailor or climbing snapdragon, is a species of flowering plant in the family Plantaginaceae. It is the sole species in genus Maurandella. It is a scrambling or climbing herbaceous perennial subshrub native to Mexico, the southwestern United States, Cuba, and the Turks and Caicos Islands, where it grows in a variety of relatively dry subtropical habitats.
Lophospermum purpusii is a scambling or climbing herbaceous perennial native to Mexico. It has tubular flowers, white at the base and red to violet elsewhere.
Rhodochiton hintonii is a climbing or sprawling herbaceous perennial native to the state of Guerrero in Mexico. It has dangling flowers, with a bell-shaped calyx and dark purple petals forming a tube. Unlike the better known Rhodochiton atrosanguineus, the petal tube is asymmetrical with two "lips".
Mabrya acerifolia, or brittlestem, is a mat-forming herbaceous perennial native to south-central Arizona. It has pale yellow tubular flowers. It was first described by Francis W. Pennell in 1924 in the genus Maurandya and transferred to Mabrya by Wayne J. Elisens in 1985. The epithet acerifolia refers to the somewhat maple-like shape of its leaves.
Mabrya geniculata is a mat-forming herbaceous perennial native to the Mexican states of Sonora and Chihuahua. It has pale yellow tubular flowers. It was first described in 1894 by Benjamin L. Robinson and Merritt L. Fernald in the genus Maurandya and transferred to Mabrya by Wayne J. Elisens in 1985.
Mabrya flaviflora is a mat-forming herbaceous perennial native to a small area in Baja California Norte, Mexico. It has pale yellow tubular flowers. It was first described by Ivan M. Johnston in 1924 in the genus Maurandya and transferred to Mabrya by Wayne J. Elisens in 1985 as Mabrya geniculata subsp. flaviflora. It was restored to a full species within Mabrya by David A. Sutton in 1988. The epithet flaviflora means yellow-flowered.
Mabrya coccinea is a mat-forming herbaceous perennial native to the Mexican state of Coahuila. It has red tubular flowers. It was first described by Ivan M. Johnston in 1950 in the genus Maurandya and transferred to Mabrya by Wayne J. Elisens in 1985. The epithet coccinea means red.
Mabrya rosei is a mat-forming herbaceous perennial native to the Mexican states of Jalisco and Zacatecas. It has tubular flowers, whitish at the base and red to red-violet at the apex. It was first described by Philip A. Munz in 1926 in the genus Maurandya and transferred to Mabrya by Wayne J. Elisens in 1985. Munz did not explain the origin of the epithet rosei but listed the collector of the type specimen as Joseph Nelson Rose.
Mabrya erecta is an upright herbaceous perennial native to Mexico – the states of Chihuahua, Coahuila, Durango, Nuevo León and possibly México. Unlike other members of the genus Mabrya, it does not form mats. It has tubular flowers, whitish at the base and pink to red-violet at the apex. It was first described by William B. Hemsley in 1882 in the genus Maurandya and transferred to Mabrya by Wayne J. Elisens in 1985. The epithet erecta means erect or upright.