Author: Jan Scholten
6. Ehretiaceae, including Cordiaceae, Heliotropiaceae.
In the Cronquist calssification Boraginales does not exist as an oder. Boraginaceae as a family includes Cordiaceae, Ehretiaceae and Heliotropiaceae and is placed together with Lennoaceae in Lamiales. Hydrophyllaceae was placed in Solanales.
In the Apg2 and the Apg3 classification Boraginales is not recognised.
In the Apg3 classification Boraginales is not recognised. Boraginaceae as traditionally defined is paraphyletic and needs the inclusion of Hydrophyllaceae and Lennoaceae to become monophyletic. Apg3 includes Boraginaceae in Lamiidae, but otherwise unplaced, but as a probable sister to Lamiales.
In the Apg4 classification Boraginales is an order in Lamiidae with only one family Boraginaceae. Boraginaceae includes Hydrophyllaceae, Cordiaceae, Ehretiaceae,Codonaceae, Heliotropiaceae.
In the Plant theory Boraginales is treated as an Order in the Subclass Lamiidae. Boraginaceea is split in Subfamilies, treated as Families in Boraginales.
Boraginales have strong Boron qualities, which has a peculiar similarity in the name. Boraginales is placed in Phase 3. The difficulty to place them fits with Phase 3.
In some recent publications Boraginaceae, as defined in the Apg3 classification, is split into several families: Boraginaceae, Cordiaceae, Ehretiaceae, Heliotropiaceae and Lennoaceae; these families comprise the Order Boraginales.
Codon was long regarded as an unusual member of Hydrophyllaceae, but in 1998, a molecular phylogenetic study showed that it is closer to Boraginaceae. Some authors have defined a resticted Boraginaceae excluding Codon en Wellstedia. They were placed in the monogeneric Families Codonaceae and Wellstediaceae. Boraginaceae is hard to characterize morphologically if it includes the genera Codon and Wellstedia.
Lennoaceae consists of the achlorophyllous holoparasites Lennoa and Pholisma. Studies indicatye that Lennoaceae form a clade within Ehretiaceae.
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.
The genus Hoplestigma in Boraginales was occasionally doubted. In 2014 a study showed it to be a close relative of Cordiaceae.
Hydrolea was thought to belong in Hydrophyllaceae for more than a century. It is now shown to belong in the order Solanales as sister to Sphenoclea.
Pteleocarpa was long placed in Boraginales, but with considerable doubt. The molecular evidence strongly supports it as sister to Gelsemiaceae.
Boraginales: inflorescence a scorpioid cyme!; two-parted gynoecium!; leaves mostly alternate, mostly with only evident midrib, if so leaves abundant, relatively narrow, thick indument; vestured pits present; flowers actinomorphic; corolla plicate; leaves hairy, rough, felty, trichomes; placentation parietal; ovary with secondary septae; pollen with pseudocolpi.
Content: pyrrolizidine alkaloids; iridoids lacking.
Hydrophyllaceae: vestured pits absent.
Boraginaceae includes ± 110 genera and ± 1600 species.
Boraginaceae: inflorescence a scorpioid cyme; a gynobasic style, and a two-part ovary that breaks into four nutlets; flowers 5 merous; bracteate inflorescences; faucal appendages, also called fornices, thickenings or inward evaginations of the corolla.
Heterostyly is common, scattered in at least nine genera among three tribes.
Codon: flowers 10 to 12-merous; fruit a capsule.
Wellstedia: flowers 4-merous; fruit a capsule.
Trichodesmeae includes Caccinia Savi and Trichodesma, is included in Cynoglossoideae; pollen with 2 to 5 pores, isocolpate.
Cynoglossoideae: nutlets with non-basal attachment; pollen 6 to 8 pores, heterocolpat; bracteate inflorescences absent.
Eritricheae, including Eritrichium, Hackelia, Lappula, Lepechiniella, Rochelia, Suchtelenia, is included in Cynoglossoideae.
Lithospermoideae: fornices absent; flowers zygoomorphic.
Variable: corolla shapes; pollen size, shape, pore number, pore position; ellipsoid pollen is ancestral.
Hilger, H & others; Molecular Systematics of Boraginaceae Tribe Boragineae Based on ITS1 and trnL Sequences, with Special Reference to Anchusa s.l.; Annals of Botany 94: 201–212; 2004.
Nazaire, Mare; Hufford, Larry; A Broad Phylogenetic Analysis of Boraginaceae: Implications for the Relationships of Mertensia; Systematic Botany, Volume 37,Number 3, pp. 758-783; 2012.
Luebert, Federico, et al, Boraginales Working Group; Familial classification of the Boraginales; TAXON 65.3; p 502–522; 2016.
Nazaire, Mare & Hufford, Larry; A Broad Phylogenetic Analysis of Boraginaceae: Implications for the Relationships of Mertensia; Systematic Botany, 37,3, pp. 758–783; 2012.