Boraginales

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Boraginales
Echium vulgare 190605.JPG
Echium vulgare
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Clade: Lamiids
Order: Boraginales
Juss. ex Bercht. & J.Presl
Families

Boraginales is an order of flowering plants in the asterid clade, with a total of about 125 genera and 2,700 species. Different taxonomic treatments either include only a single family, the Boraginaceae, or divide it into up to eleven families. Its herbs, shrubs, trees and lianas (vines) have a worldwide distribution.

Contents

Taxonomy

History

The classification of plants now known as Boraginales dates to the Genera plantarum (1789) when Antoine Laurent de Jussieu named a group of plants Boragineae, to include the genus Borago , now the type genus. However, since the first valid description was by Friedrich von Berchtold and Jan Svatopluk Presl (1820), [2] the botanical authority is given as Juss. ex Bercht. & J.Presl, where the ex refers to the prior authority of Jussieu. Lindley (1853) changed the name to the modern Boraginaceae. [3]

Jussieu divided the Boragineae into five groups. [4] [5] Since then Boraginaceae has been treated either as a large family with several subfamilies, or as a smaller family with several closely related families. [6] The family had been included in a number of higher order taxa, but in 1926 Hutchinson erected a new order, Boraginales, to include the Boraginaceae.

Although Boraginales was included in a number of taxonomic classifications including Dahlgren (1980), Takhtajan (1997) and Kubitzki (2016) [7] as an order, it was not recognized in either of two major systems, the Cronquist system [8] and the APG system. In the Cronquist system, Boraginaceae (including Cordiaceae, Ehretiaceae, and Heliotropiaceae) and Lennoaceae were placed in the order Lamiales, while the related Hydrophyllaceae was placed in Solanales.

The APG system took a broad view of Boraginaceae (Boraginaceae s.l. ), including within it the traditionally recognized families Hydrophyllaceae and Lennoaceae based on recent molecular phylogenies that show that Boraginaceae, as traditionally defined, is paraphyletic over these two families. APG III included Boraginaceae in the Euasterid I (lamiid) clade but this family was otherwise unplaced; its precise relationship to other families in the Euasterid I group remained unclear. In a phylogenetic study of DNA sequences of selected genes, Boraginales was resolved as sister to Lamiales sensu APG, but that result had only 65% maximum likelihood bootstrap support. [9]

In the 2016 APG IV system Boraginales is an order with only one family Boraginaceae, which includes the former family Codonaceae. At the time of the APG IV consensus there was insufficient support to further divide this monophyletic group further. [10] (For a complete discussion of the history of the taxonomy of Boraginales, see BWG (2016) )

Boraginales Working Group

Following the publication of APG IV, a collaborative group along similar lines to the APG, the Boraginales Working Group, [1] has published an alternative taxonomy based on the phylogenetic relationships within the Boraginaceae s.l.. [6] [11] This classification split the order into eleven families, including: Boraginaceae s.s. or s.str. , Cordiaceae, Ehretiaceae, Heliotropiaceae, and Hydrophyllaceae. A number of these were monogeneric. Boraginaceae is hard to characterize morphologically if it includes the genera Codon and Wellstedia . [12] Codon was long regarded as an unusual member of Hydrophyllaceae, but in 1998, a molecular phylogenetic study showed that it is closer to Boraginaceae, [13] and both Codon and Wellstedia have been allocated to their own families, Codonaceae and Wellstediaceae. [11] [14]

The achlorophyllous holoparasites Lennoa and Pholisma were once regarded as a family, Lennoaceae, but it is now known that they form a clade that is nested within Ehretiaceae. [15] Some studies have indicated that Hydrophyllaceae is paraphyletic if the tribe Nameae is included within it, but further studies will be needed to resolve this issue. [9]

The inclusion of the genus Hoplestigma in Boraginales was occasionally doubted until it was strongly confirmed in a cladistic study in 2014. [8] Hoplestigma is the closest relative of Cordiaceae and it has been recommended that the latter be expanded to include it.

Hydrolea was thought to belong in Hydrophyllaceae for more than a century after it was placed there by Asa Gray, but it is now known to belong in the order Solanales as sister to Sphenoclea . [9]

Pteleocarpa was long regarded as an anomaly, and was usually placed in Boraginales, but with considerable doubt. The molecular evidence strongly supports it as sister to Gelsemiaceae, [9] and that family has been expanded to include it. [16]

Related Research Articles

<span class="mw-page-title-main">Solanales</span> Order of dicot flowering plants

The Solanales are an order of flowering plants, included in the asterid group of dicotyledons. Some older sources used the name Polemoniales for this order.

<span class="mw-page-title-main">Boraginaceae</span> Family of flowering plants

Boraginaceae, the borage or forget-me-notfamily, includes about 2,000 species of shrubs, trees, and herbs in 146 to 156 genera with a worldwide distribution.

<span class="mw-page-title-main">Geraniales</span> Order of flowering plants in the rosid subclade of eudicots

Geraniales is a small order of flowering plants, included within the rosid subclade of eudicots. The largest family in the order is Geraniaceae with over 800 species. In addition, the order includes the smaller Francoaceae with about 40 species. Most Geraniales are herbaceous, but there are also shrubs and small trees.

<span class="mw-page-title-main">Geraniaceae</span> Family of plants

Geraniaceae is a family of flowering plants placed in the order Geraniales. The family name is derived from the genus Geranium. The family includes both the genus Geranium and the garden plants called geraniums, which modern botany classifies as genus Pelargonium, along with other related genera.

<span class="mw-page-title-main">Hydrophylloideae</span> Subfamily of plants

Hydrophylloideae is a subfamily of the plant family Boraginaceae. Their taxonomic position is somewhat uncertain. Traditionally, and under the Cronquist system, they were given family rank under the name Hydrophyllaceae, and treated as part of the order Solanales. More recent systems have recognised their close relationship to the borage family, Boraginaceae, initially by placing Hydrophyllaceae and Boraginaceae together in an order Boraginales, and most recently by demoting Hydrophyllaceae to a subfamily of Boraginaceae. However the placement and circumscription of Boraginaceae is still uncertain: it is unplaced at order level, and there is some prospect of it being split up again in future.

<i>Heliotropium</i> Genus of flowering plants in the borage family Boraginaceae

Heliotropium is a genus of flowering plants in the heliotrope family, Heliotropiaceae. There are around 325 species in this almost cosmopolitan genus, which are commonly known as heliotropes. They are highly toxic to dogs and cats.

<span class="mw-page-title-main">Asterids</span> Clade of eudicot angiosperms

In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade. Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total flowering plant species. Well-known plants in this clade include the common daisy, forget-me-nots, nightshades, the common sunflower, petunias, yacon, morning glory, lettuce, sweet potato, coffee, lavender, lilac, olive, jasmine, honeysuckle, ash tree, teak, snapdragon, sesame, psyllium, garden sage, table herbs such as mint, basil, and rosemary, and rainforest trees such as Brazil nut.

<i>Phacelia</i> Genus of flowering plants in the borage family Boraginaceae

Phacelia is a genus of about 200 species of annual or perennial herbaceous plants in the borage family, native to North and South America. California is particularly rich in species with over 90 recorded in the region.

Hoplestigma is a genus of flowering plants in the family Boraginaceae, although this is disputed, and it has been placed in its own family Hoplestigmataceae. Its two species are native to Cameroon, Gabon, Ivory Coast and Liberia in western tropical Africa.

<i>Wellstedia</i> Genus of flowering plants

Wellstedia is a genus of flowering plants traditionally included in the family Boraginaceae s.l., but placed in its own family, Wellstediaceae within the Boraginales order, by the Boraginales Working Group.

<span class="mw-page-title-main">Boraginoideae</span> Subfamily of plants within the borage family (Boraginaceae)

Boraginoideae is a subfamily of the plant family Boraginaceae s.s, with about 42 genera. That family is defined in a much broader sense in the Angiosperm Phylogeny Group (APG) system of classification for flowering plants. The APG has not specified any subfamilial structure within Boraginaceae s.l.

When the APG II system of plant classification was published in April 2003, fifteen genera and three families were placed incertae sedis in the angiosperms, and were listed in a section of the appendix entitled "Taxa of uncertain position".

The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy being developed by the Angiosperm Phylogeny Group (APG). Published in 2009, it was superseded in 2016 by a further revision, the APG IV system.

<i>Codon</i> (plant) Genus of flowering plants

Codon is a small genus of plants from South Africa in the family Codonaceae in the order Boraginales. The genus Codon comprises two species.

Heliotropiaceae are a cosmopolitan family of flowering plants with approximately 450 species worldwide, though it is concentrated especially in the tropics and subtropics.

<i>Cordia lutea</i> Species of plant

Cordia lutea, known as yellow cordia or in Spanish muyuyo, is a shrubby plant in the borage family (Boraginaceae), native to the Galápagos Islands, mainland Ecuador, Peru, and the Marquesas Islands in Polynesia. Common in the arid lowlands of the Galápagos, its relatively large yellow flowers make it easy to identify.

<i>Coldenia</i> Genus of flowering plants

Coldenia, named after C. Colden, is a monotypic genus of flowering plants traditionally included in the borage family, Boraginaceae sensu lato. It was assigned to the subfamily Ehretioideae, but molecular data revealed it to be more closely related to the genus Cordia, so that other authors placed in Cordioideae. Subsequently, it was placed in its own family, Coldeniaceae, within the Boraginales order, by the Boraginales Working Group.

Selkirkia is a genus of flowering plants in the family Boraginaceae. Three species occur on the South American mainland and one, Selkirkia berteroi, the first of the genus to be reported, is an endemic on Robinson Crusoe Island off the coast of Chile. It was previously considered a monotypic genus.

<i>Euploca</i> Genus of flowering plants in the borage family Boraginaceae

Euploca is an almost cosmopolitan genus of plants with around 100 species. It was first described by Thomas Nuttall in 1837. While part of the broadly defined Boraginaceae in the APG IV system from 2016, a revision of the order Boraginales from the same year includes Euploca in the separate family Heliotropiaceae. Its species used to be classified in the genera Hilgeria and Schleidenia and in Heliotropium sect. Orthostachys, but were found to form an independent lineage in a molecular phylogenetic analysis, more closely related to Myriopus than to Heliotropium. While many species use the C4 photosynthetic pathway, there are also C3–C4 intermediate species. Species have leaves with a C4-typical Kranz anatomy.

<i>Huynhia</i> Genus of flowering plants

Huynhia is a genus of flowering plants belonging to the family Boraginaceae, from Asia.

References

  1. 1 2 BWG 2019.
  2. Berchtold & Presl 1820.
  3. Lindley 1853.
  4. Jussieu 1789.
  5. d'Aillon 2016.
  6. 1 2 BWG 2016.
  7. Kadereit & Bittrich 2016.
  8. 1 2 Weigend et al 2014.
  9. 1 2 3 4 Refulio-Rodriguez, Nancy F.; Olmstead, Richard G. (2014). "Phylogeny of Lamiidae". American Journal of Botany. 101 (2): 287–299. doi:10.3732/ajb.1300394. PMID   24509797.
  10. APG 2016.
  11. 1 2 Hilger & Cole 2018.
  12. James I. Cohen. 2014. "A phylogenetic analysis of morphological and molecular characters of Boraginaceae: evolutionary relationships, taxonomy, and patterns of character evolution". Cladistics30(2):139-169. doi:10.1111/cla.12036
  13. Ferguson 1998.
  14. Peter F. Stevens (2001 onwards). "Boraginaceae" At: Angiosperm Phylogeny Website. At: Missouri Botanical Garden Website. (see External links below)
  15. Marc Gottschling, Federico Luebert, Hartmut H. Hilger, and James S. Miller. 2014. "Molecular delimitations in the Ehretiaceae (Boraginales)". Molecular Phylogenetics and Evolution72:1-6. doi:10.1016/j.ympev.2013.12.005
  16. Lena Struwe, Valerie L. Soza, Sugumaran Manickam, and Richard G. Olmstead. 2014. "Gelsemiaceae (Gentianales) expanded to include the enigmatic Asian genus Pteleocarpa". Botanical Journal of the Linnean Society175(4):482–496. doi:10.1111/boj.12182.

Bibliography

Historical sources