Alternatively Labiaceae Dulac, Labiataceae Boerl., Lamiaceae Lindl. (nom. altern.)
Including Menthaceae Burnett, Scutellariaceae Caruel
Excluding Tetrachondraceae
Habit and leaf form. Herbs (usually), or shrubs (sometimes ericoid), or trees (rarely), or lianas (rarely); characteristically bearing essential oils (the crushed foliage aromatic or foetid, with taxonomic predictability). The herbs annual to perennial; with neither basal nor terminal aggregations of leaves. Self supporting (usually), or climbing (occasionally). Helophytic, or mesophytic, or xerophytic. Leaves opposite (decussate on the usually square stem), or whorled; when whorled, 3-10 per whorl (e.g. Dysophylla); flat, or folded, or rolled, or terete; petiolate to sessile; aromatic, or foetid, or without marked odour (very rarely); simple, or compound; epulvinate; when compound, pinnate. Lamina dissected, or entire; when dissected, pinnatifid; one-veined, or pinnately veined; cross-venulate; cordate to cuneate at the base, or rounded at the base. Leaves exstipulate. Lamina margins entire, or crenate, or serrate. Leaves without a persistent basal meristem. Domatia recorded (Cuminia); represented by pockets.
Leaf anatomy. Hydathodes present (ocasionally), or absent. Abaxial epidermis not papillose. Stomata predominantly diacytic, or anomocytic, or anisocytic, or anomocytic and anisocytic. Hairs usually present; eglandular and glandular; unicellular, or multicellular. Unicellular hairs branched, or unbranched. Multicellular hairs uniseriate, or multiseriate; branched, or unbranched. Urticating hairs absent.
Adaxial hypodermis absent. Lamina dorsiventral, or isobilateral, or centric. Midrib conspicuous. Main veins embedded. Minor leaf veins without phloem transfer cells (8 genera).
Stem anatomy. Stems with solid internodes, or with spongy internodes, or with hollow internodes. Young stems usually tetragonal. Secretory cavities absent. Cork cambium present; initially deep-seated, or superficial. Nodes unilacunar (with 1 or 2 traces). Primary vascular tissue comprising a ring of bundles (four, one in each corner of the stem); centrifugal. Cortical bundles absent. Medullary bundles absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. `Included' phloem absent. Xylem without fibre tracheids; with libriform fibres; with vessels. Vessel end-walls simple. Vessels with vestured pits (rarely), or without vestured pits. Primary medullary rays wide, or mixed wide and narrow, or narrow. Wood ring porous to diffuse porous; parenchyma paratracheal (rather sparse to very sparse). Sieve-tube plastids S-type. Pith with crystalline inclusions, or without crystalline inclusions.
Reproductive type, pollination. Hermaphrodite, or dioecious, or gynodioecious (fairly commonly), or polygamomonoecious (rarely). Entomophilous, or ornithophilous; usually via hymenoptera, or via lepidoptera, or via diptera.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in `inflorescences'; in verticils (usually, these usually formed from axillary pairs of dichasial or circinate cymes), or in heads, or in spikes, or in cymes. The terminal inflorescence unit cymose, or racemose. Inflorescences terminal, or axillary. Flowers minute to medium-sized; somewhat irregular to very irregular; zygomorphic. The floral asymmetry involving the perianth and involving the androecium (though sometimes not the calyx). Flowers cyclic; tetracyclic. Floral receptacle developing a gynophore, or with neither androphore nor gynophore. Free hypanthium absent. Hypogynous disk often present, or absent.
Perianth with distinct calyx and corolla; 4-10; 2 whorled; isomerous, or anisomerous (or only dubiously interpretable). Calyx 2, or 3, or 4, or 5 (typically 5, but 2-lobed in e.g. Prostanthera, 3-lobed in Melittis, 4-lobed in e.g. Preslia); 1 whorled; variously gamosepalous; lobed, or toothed; campanulate, or funnel-shaped, or tubular; unequal but not bilabiate (one-lipped), or bilabiate, or regular; persistent; imbricate, or open in bud (e.g. Westringia); (when K 5) with the odd member posterior. Corolla supposedly 5 (but usually with no clear indication of individual petals); 1 whorled; gamopetalous; imbricate; usually bilabiate (the lower lip typically three-lobed), or unequal but not bilabiate (e.g. Teucrium, rarely almost regular as in Mentha); plain, or with contrasting markings.
Androecium 2, or 4(-5) (usually), or 8-10 (in Lachnostachys). Androecial members adnate; markedly unequal; usually free of one another, or coherent (in Coleus); in Coleus 1 - adelphous; 1 - whorled. Androecium exclusively of fertile stamens, or including staminodes. Staminodes when present, 1 (posterior), or 2 (the posterior pair, or the anterior pair). Stamens 2, or 4, or 8-10 (very rarely); didynamous (usually, with the anterior pair longer); usually reduced in number relative to the adjacent perianth (at least theoretically). Anthers connivent (in pairs, commonly), or separate from one another; dorsifixed; versatile, or non-versatile; dehiscing via longitudinal slits; introrse; unilocular to bilocular; tetrasporangiate; appendaged, or unappendaged. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or decussate. Anther wall initially with one middle layer; of the `dicot' type. Tapetum glandular. Pollen monosiphonous; shed as single grains. Pollen grains aperturate; 3 - aperturate, or 4 - aperturate, or 6 - aperturate; colpate, or colporate; 2-celled, or 3-celled.
Gynoecium 2 (the carpels deeply lobed to mimic G4). Carpels reduced in number relative to the perianth. Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior. Ovary 2 locular (originally), or 4 locular (by intrusions of the ovary wall constituting `false septa'). Gynoecium median. Styles 1; when `apical', from a depression at the top of the ovary (then the ovary deeply lobed); `gynobasic' (usually), or apical. Stigmas 2, or 1 (by reduction); 2 - lobed; dry type; papillate; Group II type. Placentation basal. Ovules 2 per locule, or 1 per locule (two per original loculus, but one per locellus); ascending; apotropous; non-arillate; anatropous, or hemianatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type. Antipodal cells formed; 3; proliferating (rarely, e.g. Physostegia), or not proliferating; ephemeral, or persistent. Synergids commonly hooked. Endosperm formation cellular. Endosperm haustoria present; usually chalazal and micropylar (the latter aggressive). Embryogeny nearly always onagrad (rarely asterad).
Fruit usually non-fleshy, or fleshy (rarely); dehiscent, or indehiscent, or a schizocarp (usually, more or less); when schizocarpic, comprising nutlets, or comprising drupelets (typically of four nutlets, distinct or cohering pairwise, enclosed in the persistent calyx); when not more or less schizocarpic, a capsule, or a drupe, or of separable pyrenes. Capsules when dehiscent, septicidal. Seeds endospermic to non-endospermic (the scant, fleshy endosperm often absorbed by the developing embryo). Embryo well differentiated (with a downward-pointing radicle, by contrast with Boraginaceae). Cotyledons 2. Embryo achlorophyllous (16/23); straight.
Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Cyanogenic (rarely), or not cyanogenic. Alkaloids present (commonly), or absent. Iridoids recorded (commonly); carbocyclic and seco-compounds. Proanthocyanidins absent. Flavonols mostly absent. Ellagic acid absent (15 species, 14 genera). Ursolic acid present. Saponins/sapogenins absent. Aluminium accumulation not found. C3 and CAM. C3 recorded in Coleus, Hedeoma, Hyptis, Leonurus, Leucas, Lycopus, Marrubium, Mentha, Monarda, Perilla, Prunella, Salvia, Stachys, Teucrium, Thymus. CAM recorded in Plectranthus. Anatomy non-C4 type (Hedeoma, Lycopus, Marrubium, Mentha, Perovskia, Phlomis, Salvia, Stachys, Teucrium, Ziziphora).
Geography, cytology. Frigid zone to tropical. Cosmopolitan. X = 5-11(+).
Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren's Superorder Lamiiflorae; Lamiales. Cronquist's Subclass Asteridae; Lamiales. Takhtajan's Subclass Asteridae; Lamianae; Lamiales. Species 3500. Genera about 210; Ajuga, Amethystea, Anisomeles, Ballota, Becium, Bystropogon, Calamintha, Cedronella, Coleus (= Plectranthus), Cunila, Dracocephalum, Elsholtzia, Endostemon, Eriope, Fuerstia, Galeopsis, Glechoma, Hedeoma, Hemigenia, Hoehnea, Horminium, Hyptis, Hyssopus, Keiskea, Lamium, Lavandula, Leonotis, Leucas, Lycopus, Marrubium, Melissa, Melittis, Mentha, Micromeria, Monarda, Monardella, Nepeta, Origanum, Paraphlomis, Perilla, Phlomis, Phyllostegia, Physostegia, Plectranthus, Pogostemon, Prasium, Prostanthera, Prunella, Pycnanthemum, Rosmarinus, Roylea, Saccocalyx, Salvia, Satureja, Scutellaria, Sideritis, Stachys, Syncolostemon, Teucrium, Thymus, Westringia, Wrixonia, Zataria, Ziziphora.
El-Gazzar and Watson 1970.
Economic uses, etc. The source, par excellence, of aromatic and antibiotic essential oils for the pharmaceutical and cosmetics industries (species of Salvia, Lavandula, Rosmarinus, Mentha, Marrubium, Pogostemon etc.), and of aromatic/flavoursome pot herbs (Salvia, Origanum, Thymus, Ocimum, Satureia etc.). Many are cultivated as ornamentals (Salvia, Ajuga, Physostegia, Monarda, Scutellaria, Nepeta, Teucrium, Stachys, Phlomis etc.).
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