Lamiaceae

Family of Lamiales

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

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.

Introduction

The Lamiaceae were first described by Martinov in 1820 and belong to the large group of eudicotyledonous seed plants within the order Lamiales. Their flowers are easily recognized by their characteristic bilabiate structure, which has become one of the defining traits of the family.

The main center of diversification is found in the Mediterranean basin, particularly in dry landscapes such as the maquis and garrigue, where soils are often rocky, calcareous, or sandy. These ecological conditions have strongly influenced the adaptive patterns and distribution of the family.

Due to the presence of distinctive aromatic compounds, numerous species are highly valued in cooking as flavoring herbs, as well as in perfumery, liqueur production, and pharmacology.

Description of Lamiaceae

Most members of this family grow as herbaceous plants, either annual or perennial, though some take on different life forms. There are also species that appear as shrubs, trees and climbers in certain regions. The surface of the plants is frequently covered with simple hairs. Stems are usually quadrangular in cross-section, due to collenchyma bundles positioned at the corners, leaving the faces slightly concave. In several species, specialized glandular structures produce essential oils responsible for distinctive aromas.

Along the stem, the leaves are typically arranged in opposite pairs, though in some cases they appear whorled or decussate. They may be either sessile or petiolate, and their shapes range from lanceolate to ovate, with margins that can be entire, lobed, or toothed. In certain taxa, pinnate leaves also occur.

The inflorescences are usually thyrsoid or racemose, consisting of axillary whorl stacked one above another. Each whorl carries several flowers, often between two and twenty, supported by large bracts that resemble leaves. The bracts of successive whorl are alternately arranged, and in some species they take on spiny, needle-like, or even brightly colored forms. Bracteoles may or may not be present.

The flowers are predominantly hermaphroditic, usually zygomorphic (especially in the corolla), and organized in tetramerous or pentamerous patterns. The calyx, generally gamosepalous and close to actinomorphic, is often made of five lobes, sometimes forming a weakly bilabiate structure.

The corolla, typically gamopetalous, develops into a tubular form ending in two distinct lips, one upper and one lower, with five lobes in total. Variations occur in some genera, where the structure departs from the typical bilabiate design. Colors are extremely diverse, and the the flower opening may be ringed with hairs that regulate access to pollinators.

The androecium generally contains four didynamous stamens, all fertile, although in some groups they are reduced to two. Filaments are attached to the corolla, and anthers are paired and may be glabrous or hairy. Pollen grains vary from tricolpate to hexacolpate, while the nectary is disk-shaped, often producing abundant nectar.

The gynoecium has a deeply four-lobed ovary, technically with 2 carpels, divided by false septa. Each ovule is tenuinucellate and solitary within its compartment. The style arises basally and ends in a bifid stigma.

The fruit is a schizocarp that typically splits into four nutlets, sometimes fewer, which can be dry or fleshy. Their surfaces vary from smooth to tuberculate, and they often release seeds readily.

Pollination usually depends on insects, carried out by bees, bumblebees, wasps, flies, butterflies, moths, and even certain birds. Fertilization follows the transfer of pollen, while dispersal strategies are diverse. Many species depend on wind dispersal, where seeds drop to the ground and are carried by the wind, or on ant dispersal, where ants gather seeds that have small, nutritious parts rich in fats, proteins, and sugars. In species with drupe-like fruits, dispersal is ensured by birds and mammals.

Classification of Lamiaceae

This family is divided into subfamilies, along with a single edible genus that cannot be placed in any specific subfamily.

Subfamilies:

• Ajugoideae (bugloss, St. John’s wort)
• Lamioideae (patchouli)
• Nepetoideae (basil, coleus, creeping glechoma, creeping mint, cunila, dragonhead, giant anise, glechoma, hyssop, lemon balm, lemongrass, mint, mint basil, oregano, rosemary, sage, thyme)

Genus:

• Callicarpa (beautyberry)