The Families of Flowering Plants

L. Watson and M. J. Dallwitz


Boraginaceae Juss.

Including Asperifoliaceae Reichb., Buglossaceae Hoffmannsegg & Link, Heliotropiaceae Schrad., Onosmaceae (Onosmataceae) Horan., Scorpiaceae Dulac

Excluding Ehretiaceae, Wellstediaceae

Habit and leaf form. Trees, or shrubs, or herbs, or lianas (a few); without essential oils. Autotrophic. Annual to perennial (often hispid or scabrid); with a basal aggregation of leaves, or with neither basal nor terminal aggregations of leaves. Self supporting (usually), or climbing. Helophytic, or mesophytic, or xerophytic. Leaves minute to medium-sized; alternate, or alternate and opposite (then opposite below); flat; petiolate to sessile; non-sheathing, or sheathing (sometimes, in basal rosettes); not gland-dotted; simple; epulvinate. Lamina entire; usually narrow, linear to lanceolate. Leaves exstipulate. Lamina margins entire (mostly), or crenate, or dentate. Leaves without a persistent basal meristem. Domatia recorded, or not recorded.

Leaf anatomy. Mucilaginous epidermis absent. Stomata on both surfaces (usually); usually anomocytic. Hairs usually present (the herbs especially characterized by hispid leaves); eglandular, or eglandular and glandular. Multicellular hairs uniseriate; branched, or unbranched. Urticating hairs absent.

Adaxial hypodermis absent. Lamina dorsiventral, or isobilateral; without secretory cavities. Cystoliths commonly present (at the bases of the hairs). The mesophyll commonly containing calcium oxalate crystals. The mesophyll crystals raphides, or druses, or solitary-prismatic. Midrib conspicuous. Main veins vertically transcurrent, or embedded. Minor leaf veins with phloem transfer cells (usually in 17 genera), or without phloem transfer cells (Caccinea, Heliotropium).

Stem anatomy. Secretory cavities absent. Cork cambium usually present; initially deep-seated, or superficial. Nodes unilacunar. Primary vascular tissue in a cylinder, without separate bundles; centrifugal. Cortical bundles absent. Medullary bundles absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. The secondary phloem not stratified. ‘Included’ phloem absent. Xylem with fibre tracheids, or without fibre tracheids; with libriform fibres, or without libriform fibres; with vessels. Vessel end-walls horizontal; simple (usually), or reticulately perforated. Vessels without vestured pits. Primary medullary rays wide (in woody species), or narrow. Wood ring porous to semi-ring porous; storied, or partially storied, or not storied; parenchyma apotracheal.

Reproductive type, pollination. Plants hermaphrodite, or dioecious (sometimes in Heliotropium), or gynodioecious (e.g. in Echium). Predominantly entomophilous; via hymenoptera.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’ (nearly always), or solitary (e.g. sometimes in Heliotropium); in cymes. The terminal inflorescence unit cymose (coiled at first). Inflorescences terminal, or axillary, or leaf-opposed; usually coiled cincinnial, sometimes double; not pseudanthial. Flowers bracteate, or ebracteate; bracteolate; usually regular, or somewhat irregular to very irregular (Echium and relatives); when irregular, somewhat zygomorphic; basically 5 merous (but Plagiobothrys sometimes with supernumerary K members); cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk present, or absent.

Perianth with distinct calyx and corolla; 10(–13); 2 whorled; isomerous (mostly), or anisomerous (sometimes in Plagiobothrys). Calyx 5 (usually), or 5–8 (sometimes in PLagiobothrys); 1 whorled; polysepalous, or gamosepalous (basally). Calyx lobes when gamosepalous, markedly shorter than the tube to markedly longer than the tube. Degree of gamosepaly (maximum length joined/total calyx length) 0.1–0.5. Calyx basally appendaged (e.g. Myosurus), or neither appendaged nor spurred; persistent (usually), or not persistent (sometimes in Heliotropium); imbricate, or open in bud, or valvate (rarely). Corolla 5; 1 whorled; appendiculate (often, with a corona of scales from the throat protecting the nectar), or not appendiculate; gamopetalous. Corolla lobes markedly shorter than the tube to markedly longer than the tube. Corolla imbricate, or contorted; rotate, or campanulate to hypocrateriform, or tubular; unequal but not bilabiate, or regular, or bilabiate (often, in Echium); green, or white, or yellow, or orange, or pink, or purple, or blue (or violet).

Androecium 5. Androecial members unbranched; adnate (to the corolla); all equal, or markedly unequal; free of one another, or coherent; 1 whorled. Androecium exclusively of fertile stamens. Stamens 5; inserted midway down the corolla tube, or in the throat of the corolla tube; not didynamous, not tetradynamous; isomerous with the perianth; oppositisepalous; filantherous to with sessile anthers. Filaments appendiculate, or not appendiculate. Anthers cohering, or separate from one another, or connivent (sometimes somewhat coherent at base and apex); dorsifixed to basifixed; dehiscing via longitudinal slits; introrse; tetrasporangiate; appendaged, or unappendaged. The anther appendages when present, apical, or basal. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral. Anther wall initially with one middle layer; of the ‘dicot’ type. Tapetum glandular. Pollen grains aperturate; 3–20 aperturate (to ‘many’); colpate, or porate, or colporate, or colpate and colporate (alternating); 2-celled, or 3-celled.

Gynoecium 2 carpelled (usually), or 4–5 carpelled (sometimes in Trigonotis). Carpels reduced in number relative to the perianth (usually), or reduced in number relative to the perianth to isomerous with the perianth (Trigonotis). The pistil 2 celled, or 4 celled (usually, via false septa), or 8–10 celled (via false septa, in some Trigonotis species). Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior. Ovary 2 locular (nearly always, but only rarely ostensibly so), or 4–5 locular (and usually ostensibly four, via false septa). Locules secondarily divided by ‘false septa’ (usually), or without ‘false septa’ (rarely). Gynoecium median; stylate. Styles 1; from a depression at the top of the ovary; ‘gynobasic’, or apical (in Heliotropoideae). Stigmas 1–2; when simple, 1–2 lobed; nearly always dry type; papillate; Group II type (usually), or Group III type (rarely). Placentation axile to basal. Ovules 2 per locule (usually separating into one-ovuled portions); horizontal to ascending; epitropous (the micropyle directed upwards); with dorsal raphe; non-arillate; anatropous, or hemianatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type, or Allium-type (sometimes). Polar nuclei fusing prior to fertilization, or fusing only after one has been fertilized (?). Antipodal cells formed; 3; not proliferating; ephemeral, or persistent. Synergids pear-shaped, or hooked. Endosperm formation cellular to nuclear. Endosperm haustoria present, or absent; micropylar (Heliotropium). Embryogeny onagrad, or chenopodiad.

Fruit fleshy, or non-fleshy; when dry, dehiscent, or indehiscent, or a schizocarp. Mericarps when schizocarpic, 4, or 8–10 (sometimes, in Trigonotis); comprising nutlets, or comprising drupelets. Fruit a drupe (1–4 seeded). The drupes with separable pyrenes (two or four). Seeds endospermic, or non-endospermic. Embryo well differentiated (the radicle directed upwards, by contrast wih Labiatae). Cotyledons 2. Embryo achlorophyllous (14/17); straight, or curved.

Seedling. Germination phanerocotylar, or cryptocotylar.

Physiology, biochemistry. Cyanogenic (rarely), or not cyanogenic. Alkaloids present, or absent. Iridoids not detected. Proanthocyanidins absent. Flavonols present (usually), or absent (Echium); kaempferol and quercetin (usually), or quercetin. Ellagic acid absent (11 species, 9 genera). Saponins/sapogenins absent. Inulin recorded (Cynoglossum). C3 and C4. C3 physiology recorded directly in Arnebia, Coldenia, Heliotropium, Lappula, Lithospermum, Moltkiopsis, Onosmodium, Trichodesma. C4 physiology recorded directly in Heliotropium. Anatomy C4 type (Heliotropium), or non-C4 type (Arnebia, Cynoglossum, Echiochilon, Heliotropium, Heterocaryum, Lappula, Lithospermum, Myosotis, Onosma, Onosmodium, Trichodesma, Vaupelia).

Geography, cytology. Holarctic, Paleotropical, Neotropical, Cape, Australian, and Antarctic. Temperate to tropical. Cosmopolitan, but fewer in cool temperate and tropical regions, and with a strong Mediterranean concentration. X = 4–12.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Solaniflorae; Boraginales. Cronquist’s Subclass Asteridae; Lamiales. APG (1998) Eudicot; core Eudicot; Asterid; Euasterid I; unassigned at ordinal level. Species 2000. Genera about 120; Actinocarya, Adelocaryum, Afrotysonia, Alkanna, Amblynotus, Amphibologyne, Amsinckia, Anchusa, Ancistrocarya, Anoplocaryum, Antiotrema, Antiphytum, Arnebia, Asperugo, Auxemma, Borago, Bothriospermum, Brachybotrys, Brunnera, Buglossoides, Caccinia, Carmona, Cerinthe, Chionocharis, Choriantha, Craniospermum, Cryptantha, Cynoglossopsis, Cynoglossum, Cynoglottis, Cysostemon, Dasynotus, Decalepidanthus, Echiochilon, Echiostachys, Echium, Elizaldia, Embadium, Eritrichium, Gastrocotyle, Gyrocaryum, Hackelia, Halacsya, Heliocarya, Heliotropium, Heterocaryum, Huynhia, Ivanjohnstonia, Ixorhea, Lacaitaea, Lappula, Lasiarrhenum, Lasiocaryum, Lepechiniella, Lepidocordia, Lindelophia, Lithodora, Lithospermum, Lobostemon, Macromeria, Maharanga, Mairetis, Mattiastrum, Mertensia, Metaeritrichium, Microcaryum, Microula, Mimophytum, Moltkia, Moltkiopsis, Moritzia, Myosotidium, Myosotis, Neatostema, Nesocaryum, Nogalia, Nomosa, Nonea, Ogastemma, Omphalodes, Omphalolappula, Omphalotrigonotis, Onosma, Onosmodium, Oxyosmyles, Paracaryum, Pardoglossum, Patagonula, Pectocarya, Pentaglottis, Perittostema, Plagiobothrys, Pseudomertensia, Psilolaemus, Pteleocarpa, Pulmonaria, Rindera, Rochefortia, Rochelia, Rotula, Saccellium, Scapicephalus, Selkirkia, Sericostoma, Sinojohnstonia, Solenanthus, Stenosolenium, Stephanocaryum, Suchtelenia, Symphytum, Thaumatocaryum, Thyrocarpus, Tianschaniella, Tiquilia, Tournefortia, Trachelanthus, Trachystemon, Trichodesma, Trigonocaryum, Trigonotis, Ulugbekia, Valentiniella.

Economic uses, etc. Ornamentals, pot herbs, dyes for wood, stone, medicines, wines and cosmetics, and some important honey plants.

Illustrations. • Boragineae (Synphytum, Borago, Anchusa, Pentaglossis). • Lithospermeae (Myosotis, Lithospermum). • Lithospermeae (Mertensia), Cynoglosseae, Echieae. • Technical details. • Technical details. • Technical details.

Quotations

Then the blossoms blue to the bank he threw
Ere he sank in the eddying tide;
And ‘Lady, I’m gone, thine own knight true,
Forget me not’, he cried
(Bishop Mant, quoted by Ann Pratt, ‘Wild Flowers’ (1857) - Myosotis palustris)

And laden barges float
By banks of myosote
(Robert Bridges (1844–1930), ‘There is a Hill’)

Borage and Hellebore fill two scenes,
Sovereign plants to purge the veins
Of melancholy, and clear the heart
Of those black fumes which make it smart
(Burton, quoted by Ann Pratt, ‘Wild Flowers’ (1857) - Borago officinalis)


Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).

Index