|Clothilde PATOUX, University of Thessaloniki, April 2000.
Family of Lamiaceae (Labiatae)
The family Lamiaceae belongs to:
Division Magnioliophyta:Angiosperms (flowering plants)
Class Magnoliatea (Dicotyledons)
With 2 other fairly large families: Boraginaceae and Verbenaceae, in addition to a very small family, the Lennoaceae (fleshy parasites that invade roots).
Aside from the Lennoaceae, members of the Lamiales are green plants with a superior ovary composed of a small number of carpels (typically two), with each carpel forming two small compartments that contain a single ovule each. The fruit very often consists of single-seeded, half-carpellary nutlets.
This classification is subject to discussions (Then Dahlgren
One example: defined the Superorder Lamiiflorae).
Habit: Herbs (usually), or shrubs (sometimes ericoid), or trees (rarely), or lianas (rarely). The herbs are annual to perennial. These plants characteristically bear essential oils (the crushed foliage aromatic or fetid, with taxonomic predictability). Most members of the family have square stems.
Leaves: With some exceptions, plants of the Lamiales possess simple, opposite leaves (decussate on the usually square stem), or whorled. When whorled: 3–10 per whorl (e.g. Dysophylla). They are flat, or folded, or rolled; mostly ‘herbaceous’ or leathery, or fleshy; petiolate to sessile. These leaves are often aromatic, or fetid, very rarely without marked odor. Hairs usually present (usually with conspicuous glandular hairs).
The leaves can be simple, or compound; epulvinate; when compound, pinnate.
Inflorescence: flowers solitary or aggregated in “inflorescences”. Inflorescence is a raceme in which the lowest flowers of the branched system open first and is terminal or axillary.
An example of genus with inflorescence: Monarda
Flowers: minute to medium-sized; somewhat irregular to very irregular.
Zygomorphic. The bilabiate corolla characterizes the Lamiaceae family.
The typical floral formula is: K (5) C (5) A2 or 2+2G(2)
Most genera produce bisexual flowers bearing both stamens and pistils.
A representative flower is four- or five-parted, sepals are partially fused to form a bell-shaped calyx, and petals form a tubular corolla that is two-lipped. Typically two united carpels form the pistil.
Perianth has distinct calyx and corolla. 2 whorled.
Then, the calyx consists basically in 5 sepals (often with the bilabiate condition superimposed); 1 whorled; entire (occasionally), or blunt-lobed, or toothed. It is campanulate, or funnel-shaped, or tubular, unequal but not bilabiate (one-lipped), or bilabiate, or regular, with the median member posterior when K5.
The corolla is compound by 5 more or less disguisedly sepals (usually with no clear indication of individual petals -commonly with five lobes, but usually with the bilabiate condition superimposed, and the five lobes variously secondarily lobed, reduced or suppressed), or 4 (occasionally, ostensibly, e.g. Mentha); 1 whorled, most of the time bilabiate.
The androecium (2, or 4 usually) is 1 whorled. It exclusively consists of fertile stamens, or including staminodes. The stamens are usually 4, with one longer and one shorter pair, but they can be just 2, usually inserted midway down the corolla tube, or in the throat of the corolla tube (and sometimes the pairs attached at different levels), or rarely near the base of the corolla tube (e.g. Teucrium). The anthers are connivent (in pairs, commonly), or separate from one another; dehiscing via longitudinal slits, tetrasporangiate.
The gynoecium consists in 2 carpels (deeply lobed). It is superior and median. Styles 1. Ovules are usually 2 per locule.
Reproduction, pollination: These plants are hermaphrodite, or dioecious, gynodioecious (fairly commonly).
The pollination is Entomophilous, or ornithophilous. It usually occurs via hymenoptera, lepidoptera, or diptera.
Fruit: usually non-fleshy, or fleshy (rarely); more or less a schizocarp. They typically consist in four nutlets, distinct or cohering pairwise, enclosed in the persistent calyx. Seeds endospermic to non-endospermic (the scant, fleshy endosperm often absorbed by the developing embryo). Embryo well differentiated. 2 Cotyledons, flat.
Cosmopolitan. The members of the Lamiaceae family are found from Frigid Zone to Tropical Zone.
Representative genera and species
Lamiacea is a large family. It content between 160 and 210 genera, and more than 3500 species. According to Cronquist’s classification the most well-known genera of this family being certainly:
- Lamium (40 to 50 species, known as dead nettles)
Thymus (about 300 to 400 species, all Eurasian). Among them is the garden thyme (T. vulgaris), the source of the kitchen herb.
Mentha (roughly 3,200 species)
Origanum (15 to 20 species) includes, chief among them being marjoram (Origanum majorana), or Majorana hortensis
Rosmarinus, with the best known for its sharp fragrance rosemary (Rosmarinus officinalis), a Mediterranean species.
Lavendula among which is the specie lavender (Lavandula officinalis), with fragrant blue to lavender flowers in leafless spikes.
Phlomis (approximately 100 species)
Ocimum, with Ocimum basilicum, the sweet basil.
Hyssopus, Hyssopus officinalis was once used as a curative herb
Nepeta with the catnip, or catmint (Nepeta cataria)
Lots of economic uses: the source, par excellence, of aromatic and antibiotic essential oils for the pharmaceutical and cosmetics industries, and of aromatic/flavoursome pot herbs.
Spice plants include marjoram (Origanum majorana), European marjoram (O. vulgare), sweet basil (Ocimum basilicum), sage (Salvia officinalis), savory (Satureja hortensis), lemon balm (Melissa officinalis), and thyme (Thymus vulgaris).
Perfumes are derived from lavender (Lavandula angustifolia) and rosemary (Rosmarinus officinalis).
The oils from horehound (Marrubium vulgare) and clary (Salvia sclarea) have medicinal value.
Many are cultivated as ornamentals (Salvia, Ajuga, Physostegia, Monarda, Scutellaria, Nepeta, Teucrium, Stachys, Phlomis etc.).
Calamintha grandiflora Teucrium orientale
http://www.wisc.edu/botit/img/bot/401/ (Labium album and drawings)
http://botany.about.com/education/botany/ (Monarda, Thymus necefii, Prunella vulgaris and Teucrium orientale)
http://www.euronet.nl/users/mbleeker/folis/bsmain-e.html (Origanum vulgare, Scutellaria balcalensis, Calamintha grandiflora, Salvia glutinosa and Lavendula stoeches)