| Antirrhineae | |
|---|---|
 | |
| A nectar spur and a bright yellow "tongue" spot, as in these Linaria reflexa flowers, are widespread traits among the Antirrhineae | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Lamiales |
| Family: | Plantaginaceae |
| Tribe: | Antirrhineae Dumort. [1] |
| Genera | |
About 30, see text | |
The Antirrhineae are one of the 12 tribes of the family Plantaginaceae. It contains the toadflax relatives, such as snapdragons.
Most Antirrhineae are herbaceous, short-lived, perennial or annual plants growing at most about a metre/yard tall when in full flower; the maximum height of most species is half as much or less. Some are prostrate or twining. The flowers are often conspicuous, tubular with a basal appendix (spur, gibbous, or saccate) containing nectaries, and may be of any color, though yellow and blue/purple hues are most common. Multicolored flowers are a common occurrence in this tribe; a typical pattern is one conspicuous whitish or bright yellow or reddish spot at the lower outer edge of the flower tube, looking like a protruding tongue. Other characters include poricidal dehiscent capsule fruit, and the possession of iridoid glycosides. [2]
The Antirrhineae are not noted as food- or fodder plants, probably due to the iridoid content making them less than palatable. However, the tribe does not seem to contain highly poisonous plants, either; rather, use in folk medicine has been documented for a few species. While e.g. common toadflax (Linaria vulgaris) is credited with a range of uses by European herbalists, as of the 2010s, little scientific study has been made and the traditionally attested medical properties of the Antirrhineae are by and large unremarkable by standards of the Plantaginaceae, which abound with species of major pharmacological interest. The chief human use of the present tribe is for the flowers, primarily as ornamental plants in gardening. Colloquially called "the snapdragon", Antirrhinum majus is probably the single most widely known member of the Antirrhineae by far.
Antirrhinum majus cultivars can today be encountered essentially anywhere between Earth's polar circles, whether grown in a range of sizes and colours by hobbyists or field-scale for sale as cut flowers. In the hottest parts of the globe, it dies after one flowering, and in arid regions, other species may be more important, but otherwise it is extremely adaptable, and in warm-temperate climates, individual plants may survive for several years. The readiness with which A. majus flower colour and shape mutate and can be crossbred has led to the establishments of unusual (e.g. peloric) cultivars, as well as to making this species one of the first model organisms of genetics and helping uniting the theories of Darwin and Mendel. It remains a key model organism today in fields such as plant developmental genetics. Common toadflax has become established as a model organism more recently; while it may be an invasive nuisance weed in agriculture, like other toadflaxes and snapdragons, its attractive flowers make it useful as a wildflower. At present however, the other members of this family are generally only of minor or localized interest. [3]
The Antirrhineae include about 30 genera with roughly 320 species, of which 150 are in genus Linaria . The type genus is Antirrhinum L. [4] [5]
Antirrhineae are probably most closely related to the turtlehead tribe (Cheloneae) and/or a large and badly resolved core group of their family including plants as diverse as water-starworts (Callitriche), foxgloves (Digitalis), and speedwell (Veronica).
As the Antirrhineae have long been considered a distinct group, there has also been a long debate about recognition of distinct subdivisions. In 1909, Rouy [6] separated the snapdragon-like subtribe Linarieae from the open-mouthed Anarrhineae and the monotypic Rhodochitoneae, the latter due to their petal-like calyx. By the mid-20th century, Rothmaler on morphological grounds identified five subtribes containing 21 genera: [7] [8]
Some 21st-century phylogenetic analyses indicate some quite different lineages. Mainly, the earlier authors seem to have overlumped the snapdragon-like forms (including toadflaxes) which actually do not seem to be closely related, while overemphasizing the morphological diversity of the true snapdragon relatives. As early as 1982, [9] Speta had realized that the typical toadflaxes (including Nuttallanthus ) were a lineage well apart from the snapdragons and similar genera, and established the Antirrhininae for the latter. In 2000, combining internal transcribed spacer (ITS) and morphological data from 16 genera, Ghebrehiwet et al [10] confirmed Rothmaler's proposal of a close relationship between the fairly dissimilar-looking Maurandya and Rhodochiton and the distinctness of their lineage from the bulk of the subfamily. However, they found the "Linarieae" hard to resolve, but could already tell that Kickxia should be moved to the Anarrhinae, and Asarina and Cymbalaria to the Maurandyinae. In addition, Mohavea was recognized as a snapdragon relative with extremely modified flowers, refuting a monotypic Mohaveinae. Vargas et al in 2004 [2] found six probable clades based on ITS and ndhF sequences of 22 genera, which they labelled as:
However, they also noted profound morphological diversity amongst the Antirrhinum group, in accordance with the proliferation of segregated genera.
Using ITS data from all 29 then-recognized genera, the 2013 study of Fernández-Mazuecos et al. [5] identified six similar clades. They were able to assign all these genera to one of these clades, which they labelled as:
The most striking difference between the 2004 and 2013 results is the precisely inverted placement of Galvezia and Gambelia (one as core of a distinct clade, [12] the other close to Antirrhinum as part of the Sairocarpus complex). Given the highly similar datasets and analyses, a clerical error confusing the two generic names might be suspected, but considering that the 2013 study included two species of each genus which congruently resolved as sister taxa, hybrid introgression, or a disparity between nuclear (ITS) and chloroplast (ndhF) evolution or some other divergence [13] seems a more likely cause. The erratic behavior of the two genera was noted by Vargas et al but not discussed in Fernández-Mazuecos et al.; adding to the confusion, Ghebrehiwet et al found a strongly supported Galvezia fruticosa - Gambelia speciosa clade excluding Pseudorontium and Schweinfurthia and equidistant from the true snapdragons and toadflaxes, entirely in line with Rothmaler's Gambeliinae. Furthermore, several species were historically moved between the two genera without authors noting anything suggesting against a very close relationship between them.
Regarding internal phylogeny, at present, resolution is insufficient. In the more recent studies, the Chaenorhinum clade is fairly robustly resolved as sister to the true snapdragons, but otherwise not much is clear. Except for the Antirrhinum-Chaenorhinum and Linaria clades, all main lineages have resolved as basal in one recent study or another, but the proposed interrelationships between the clades/subtribes other than Antirrhinum-Chaenorhinum are at most tenuously supported in all of them. As it seems, however, Rothmaler's general concept of an ancestral radiation of basal lineages and a subsequent diversification of the toadflax-snapdragon group was essentially correct, even though he overlumped the latter.
As of 2013, 29 genera are included in the Antirrhineae. Listed by clade, they are: [5] [2]
Lafuentea Lag. is a highly distinct Plantaginaceae genus containing a mere two species from the Strait of Gibraltar region. It is included in the present tribe by GRIN, [16] whereas other authors have variously allied it with the foxgloves (Digitalis) or even united with the equally puzzling Oreosolen and Ourisia in a lineage close to the broomrape Rehmannia as part of the Scrophulariaceae sensu lato . [4] In the 2013 study [5] as well as in the 2005 Plantaginaceae analysis by Albach et al. [4] Lafuentea indeed tends to resolve as an additional and basalmost lineage (subtribe in Linnean taxonomy) of the Antirrhineae, far from Digitalis, Oreosolen, Ourisia or Rehmannia; in fact, these five genera are apparently all distinct from each other at least at tribal level (Oreosolen and Rehmannia are even outside the Plantaginaceae). However, the results were not unequivocal and support for including Lafuentea in the Antirrhineae not very robust. Besides, the interrelationships of the Plantaginaceae tribes are also not at all robustly resolved, and some fairly close relatives of the Antirrhineae – such as Campylanthus or the singular Hemiphragma – have similarly uncertain positions as Lafuentea with regard to their presumed closest relatives. [4] Thus, while Lafuentea seems to be a "living fossil" from near the origin of the Antirrhineae and is certainly highly useful as an outgroup in cladistic studies of their internal relations, whether its placement within this tribe is correct requires further study.
Antirrhinum is a genus of plants commonly known as dragon flowers or snapdragons because of the flowers' fancied resemblance to the face of a dragon that opens and closes its mouth when laterally squeezed. They are also sometimes called toadflax or dog flower. They are native to rocky areas of Europe, the United States, Canada, and North Africa. Antirrhinum species are widely used as ornamental plants in borders and as cut flowers.
Linaria is a genus of almost 200 species of flowering plants, one of several related groups commonly called toadflax. They are annuals and herbaceous perennials, and the largest genus in the Antirrhineae tribe of the plantain family Plantaginaceae.
Toadflax is the common name of several related genera of plants in the family Plantaginaceae, including:
Cymbalaria is a genus of about 10 species of herbaceous perennial plants previously placed in the family Scrophulariaceae, but recently shown by genetic research to be in the much enlarged family Plantaginaceae.
Plantaginaceae, the plantain family, is a large, diverse family of flowering plants in the order Lamiales that includes common flowers such as snapdragon and foxglove. It is unrelated to the banana-like fruit also called "plantain." In older classifications, Plantaginaceae was the only family of the order Plantaginales, but numerous phylogenetic studies, summarized by the Angiosperm Phylogeny Group, have demonstrated that this taxon should be included within Lamiales.
Rehmannia is a genus of seven species of flowering plants in the order Lamiales and family Orobanchaceae, endemic to China. It has been placed as the only member of the monotypic tribe Rehmannieae, but molecular phylogenetic studies suggest that it forms a clade with Triaenophora. Contrary to the immense majority of the taxa of Orobanchaceae, Rehmannia is not parasitic.
Nuttallanthus is a genus of four species of herbaceous annuals and perennials that was traditionally placed in the foxglove family Scrophulariaceae. Due to new genetic research, it has now been placed in the vastly expanded family Plantaginaceae. Three species of Nuttallanthus are native to North America and one to South America. Nuttallanthus was until the 1980s included in a wider circumscription of the genus Linaria, a genus now considered restricted to the Old World.
Linaria vulgaris, the common toadflax, yellow toadflax or butter-and-eggs, is a species of flowering plant in the family Plantaginaceae, native to Europe, Siberia and Central Asia. It has also been introduced and is now common in North America.
Antirrhinum majus, the common snapdragon, is a species of flowering plant belonging to the genus Antirrhinum. The plant was placed in the family Plantaginaceae following a revision of its prior classical family, Scrophulariaceae.
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.
Cymbalaria muralis, commonly called ivy-leaved toadflax or Kenilworth ivy, is a low, spreading, viney plant with small purple flowers, native to southern Europe. It belongs to the plantain family (Plantaginaceae), and is introduced to many other temperate locations. The flower stalk is unusual for seeking light until it is fertilized, after which it grows away from the light. Other names include coliseum ivy, Oxford ivy, mother of thousands, and wandering sailor.
Asarina is a flowering plant genus of only one species, Asarina procumbens Mill. the trailing snapdragon, which is native to France and Spain and introduced in Germany, Switzerland, Austria and Hungary. Originally placed in the Scrophulariaceae, the genus has more recently been moved to the Plantaginaceae. Species from North America formerly placed in the genus Asarina are now placed in Holmgrenanthe, Lophospermum, Mabrya and Maurandya, as well as Neogaerrhinum. Asarina is now regarded as exclusively an Old World genus.
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.
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.
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.
Sairocarpus is a genus of the family Plantaginaceae, and is one of a group of plants commonly known as 'snapdragons'. It has ten accepted species and is being considered to include many species formerly considered as New World species of Antirrhinum.
Neogaerrhinum is a genus of the family Plantaginaceae, and is one of a group of plants commonly known as 'snapdragons'. It has two accepted species and includes species formerly considered as New World members of Antirrhinum.
Gambelia is a genus of flowering plants in the Antirrhineae tribe of the plantain family commonly known as bush snapdragons. This genus is native to northwestern Mexico, particularly the Baja California Peninsula, but species are also found on the coast of Sonora, Guadalupe Island, and the Channel Islands of California. The genus is named in honor of William Gambel (1823–1849), an American naturalist, ornithologist, and botanist.
Gambelia juncea is a species of flowering shrub in the plantain family commonly known as the Baja California bush snapdragon or Baja bush snapdragon. Gambelia juncea is a highly variable woody perennial to 1 m (3.3 ft) characterized by long, arching, reed-like stems and showy, bright red, two-lipped tubular flowers. Native to the Baja California peninsula and coastal Sonora, this species is widespread in the region across numerous habitats and has several varieties. It was formerly placed in the primarily South American genus Galvezia, but taxonomic studies have supported the reclassification of the two North American species into Gambelia. This species, with a number of cultivars, is widely used as an ornamental shrub for xeriscaping, erosion control, native plant gardens, and wildlife gardens.
