Plant Family Classification: A Comprehensive Guide

Plant Family Classification

Cruciferae (Brassicaceae)

Characteristics:

  • Leaves: Alternate, simple, pubescent, without stipules.
  • Inflorescences: Racemose.
  • Flowers: Bisexual, actinomorphic, with 4 sepals, 4 petals, 6 tetradynamous stamens, and a superior ovary.
  • Fruit: Silique (long) or silicula (short).

Distribution:

Temperate zones of the Mediterranean region.

Genera:

Brassica, Alyssum, Raphanus, Barbarea, Arabis, Cardamine, Draba, Sisymbrium, Capsella, Lepidium, Cakile, Iberis

Economic Importance:

Food, ornamental, and weeds.

Leguminosae (Fabaceae)

Characteristics:

  • Leaves: Simple or bipinnate, with or without stipules.
  • Flowers: Actinomorphic or zygomorphic, with free or partially united petals, numerous or few stamens, and a superior monocarpelar gynoecium.
  • Fruit: Legume.

Distribution:

Cosmopolitan.

Genera (Subfamilies):

  • Mimosoideae: Mimosa, Prosopis, Acacia
  • Caesalpinoideae: Ceratonia, Cercis, Cassia
  • Papilionoideae: Sophora

Economic Importance:

Timber, ornamental, drugs, and food.

Umbelliferae (Apiaceae)

Characteristics:

  • Leaves: Alternate, often divided, sheathing at the base.
  • Inflorescences: Simple or compound umbels.
  • Flowers: Bisexual, actinomorphic, with 5 sepals, 5 petals, 5 stamens, and a bicarpelar inferior gynoecium.
  • Fruit: Schizocarp with a small embryo and oily endosperm.

Distribution:

Northern temperate zone, cosmopolitan, and high altitudes in the tropics.

Genera (Subfamilies):

  • Hydrocotyloideae: Hydrocotyle, Centella
  • Saniculoideae: Sanicula, Astrantia
  • Apioideae: Eryngium

Economic Importance:

Food flavorings, ornamentals; some are poisonous.

Labiatae (Lamiaceae)

Characteristics:

  • Leaves: Opposite or whorled, simple, without stipules.
  • Inflorescences: Axial or whorled.
  • Flowers: Bisexual, zygomorphic, with a united calyx of 4 sepals, a united corolla of 5 petals, 2 or 4 stamens, and a bicarpelar syncarpous gynoecium.
  • Fruit: Group of 4 nutlets, each with a seed.

Distribution:

Cosmopolitan, with a focus on the Mediterranean.

Genera:

Lamium, Ajuga, Mentha, Rosmarinus, Coleus, Ocimum, Lavandula

Economic Importance:

Condiments, food flavorings, and ornamentals.

Compositae (Asteraceae)

Characteristics:

  • Leaves: Alternate or opposite, simple, without stipules.
  • Inflorescences: Chapters with flowers on a receptacle.
  • Flowers: Bisexual or unisexual, actinomorphic or zygomorphic, with a pappus forming a calyx, a united corolla of 5 petals, 5 stamens, and a bicarpelar syncarpous inferior gynoecium.
  • Fruit: Cypsela.

Distribution:

Cosmopolitan.

Genera (Subfamilies):

  • Lactucoideae (Cichorioideae): Sonchus, Cirsium
  • Asteroideae: Calendula, Helianthus, Senecio

Economic Importance:

Ornamentals and weeds.

Gramineae (Poaceae)

Characteristics:

  • Leaves: In 2 rows, alternating, parallel veins, with a sheathing base and ligule.
  • Inflorescences: Spikes, racemes, or panicles.
  • Flowers: Bisexual or unisexual, with 2 bracts (lemma and palea), 3 stamens, and a gynoecium with 2 or 3 carpels.
  • Fruit: Caryopsis with starchy endosperm.

Distribution:

All regions of the world.

Genera (Subfamilies):

  • Bambusoideae
  • Arundinoideae
  • Chloridoideae
  • Panicoideae
  • Pooideae (Festucoideae)

Economic Importance:

Food, industry, construction, lawns, and ornamentals.

Rosaceae

Characteristics:

  • Leaves: Alternate, simple or compound, with stipules.
  • Inflorescences: Solitary flowers or racemose and cymose groups.
  • Flowers: Bisexual, actinomorphic, with 5 sepals, 5 petals, numerous stamens, and 1 to many separate carpels or 5 to 10 carpels together.
  • Fruit: Achene, follicle, pome, or drupe. Seeds without endosperm.

Distribution:

Cosmopolitan, more common in the northern temperate zone.

Genera:

Prunus, Pyrus, Rubus, Fragaria, Malus

Economic Importance:

Fruit and ornamentals.

Fagaceae

Characteristics:

  • Leaves: Alternate, simple, pinnate.
  • Inflorescences: Monoecious plants with solitary male flowers in catkins or capitate and solitary female flowers.
  • Flowers: Unisexual, without petals. Male flowers with 4 to 7 calyx lobes and 4 to 40 stamens. Female flowers with 4 to 6 calyx lobes and a gynoecium with 3 to 6 carpels.
  • Fruit: Achene with a solitary seed.

Distribution:

Cosmopolitan, except for Africa.

Genera:

Fagus, Castanea, Quercus

Economic Importance:

Wood, cork, ornamentals, and shade.

Liliaceae

Characteristics:

  • Leaves: Alternate and simple.
  • Inflorescences: Racemose, axillary, umbellate, or solitary.
  • Flowers: Bisexual, actinomorphic, with 3 sepals, 3 petals, 3, 6, or 12 stamens, and a tricarpelar syncarpous superior or inferior gynoecium.

Distribution:

Global.

Genera:

Asparagus, Allium, Lilium

Economic Importance:

Ornamental horticulture.

Lauraceae

Characteristics:

  • Leaves: Alternate, simple, pinnate.
  • Inflorescences: Bisexual, actinomorphic.
  • Flowers: With 6 sepals, no petals, 4 whorls of 3 stamens, and a monocarpelar superior gynoecium.
  • Fruit: Drupe or berry with 1 seed.

Genera:

Cinnamomum, Persea, Laurus

Economic Importance:

Contain aromatic oils and barks.