Nepetoideae

Subfamily of Lamiaceae

Food, Plant source foods, Flowering plats (angiospermae), Mesangiosperms, Eudicots, Core eudicots, Superastierds, Asterids, Lamiids (Euasterids I), Lamiales, Lamiaceae

Consumption area(s): Earth

Note: For better understanding, please read the article on flowering plants (angiospermae) first. If you come across unfamiliar words, you can click on any highlighted term to open the glossary with definitions of key botanical terms.

Inotroduction

The Nepetoideae, with an estimated 3,100–3,700 species, represent the most species-rich branch within the Lamiaceae. Their extraordinary diversity sets them apart from other lineages of the group.

This subfamily encompasses a wide range of aromatic and medicinal plants, many of which are deeply rooted in culinary traditions and herbal practices. Among the most recognizable are basil, savory, lavender, mint, oregano, rosemary, sage, thyme, and lemon balm.

Description of Nepetoideae

The members of this subfamily show remarkable variation in their growth form. Most are herbaceous or shrub-like, with either annual or perennial life cycles, but in certain cases they appear as small trees. Some are strongly aromatic, while others display specialized traits such as geoxylic structures hidden underground, or develop as succulent species.

Additional adaptations include the presence of rhizomes, stolons, tubers, as well as more unusual reproductive systems like cleistogamy. In many taxa, the stem is distinctly quadrangular due to bands of collenchyma at each corner, and their surfaces may carry sessile glands or glandular hairs.

The leaves usually appear in opposite pairs along the stem, with each whorl alternating from the previous one. They lack stipules, and their blades may range from simple to pinnatisect, or take forms that are orbicular, reniform, ternate, or four-foliate. Margins can be entire or toothed, either shallowly or deeply.

Their inflorescences are highly variable but most often appear as cymose thyrses. These can be supported by a peduncle or not, arranged in axillary whorls stacked along the stem, branching in a dichasial pattern. Each whorl typically carries one or more sessile flowers in a circular crown, subtended by bracts of diverse shapes, from ovate to lanceolate, sometimes divided or even spiny. Smaller bracteoles may be absent or, when present, needle-like, lobed, or brightly colored.

The flowers are generally hermaphroditic, mostly zygomorphic, and organized into four floral whorls: calyx, corolla, androecium, and gynoecium. They are typically tetramerous but with five-parted calyx and corolla. The calyx is fused into a tubular or campanulate structure, ending in lobes that may form two lips in varied numerical arrangements. In some species the calyx bears up to eight or ten lobes, and persists into fruiting.

The corolla is usually bilabiate, with a tubular base that may be straight, curved, swollen, or even spurred. The upper lip tends to be entire or slightly notched, while the lower lip is three-lobed and more prominent. Colors span red, purple, pink, orange, white, blue, and lavender, with yellow being rare.

The androecium typically consists of four stamens, arranged in didynamous pairs, though in some taxa the posterior pair reduces to staminodes or disappears. Filaments are attached to the corolla, and the anthers bear two sacs that dehisce longitudinally. Pollen grains are usually tricolpate or hexacolpate. A nectary disk, often divided into four lobes, secretes abundant sugary substances.

The gynoecium has 2 carpels, but the ovary is divided into four chambers by false septa. It bears a ginobasic style ending in a bifid stigma, the lobes typically unequal. Ovules are four, tenuinucellate, and each enclosed in a single integument.

The fruit is a schizocarp, splitting into one to four nutlets. These can be globose, obovoid, or trigonous, with surfaces smooth, wrinkled, or warted, occasionally fleshy, and often dark brown. Some nutlets are mucilaginous, aiding in dispersal.

Pollination occurs primarily through insects such as flies and hymenopterans. Seed dispersal involves both wind and ants. The seeds are equipped with elaiosomes, lipid- and sugar-rich appendages that attract ants, ensuring wider distribution.

Classification of Nepetoideae

This subfamily is further divided according to the genus (if a genus includes only one edible species, reference will lead directly to that species’ page):

• Agastache (agastache)
• Cuminum (cumin)
• Hyssopus (hyssop)
• Lavandula (lavender)
• Melissa (lemon balm)
• Mentha (mint)
• Ocimum (basil)
• Origanum (oregano)
• Perilla (perilla)
• Prunella (self-heal)
• Salvia (chia seeds, sage, rosemary)
• Satureja (savory)
• Thymus (thyme)