EUPHORBIACEAE: CHARACTERISTICS, HABITAT, GENERA AND SPECIES - BIOLOGY - 2025

The Euphorbiaceae are one of the largest and most diversified families of angiosperms or flowering plants. They include herbaceous plants, shrubs or trees, and some succulents. It is made up of more than 227 genera and 6487 species, of which 6482 exist today and the other 5 are already extinct.

Regarding its distribution, being such a cosmopolitan family, it is present in a vast majority of tropical or subtropical areas, although it can also be found in temperate areas.

Species of the genus Euphorbia, belonging to the Euphorbiaceae family. Source: pixabay.com

With respect to its uses, it stands out in the production of food, medicine and industrial products (oils, waxes, gums, poisons, rubber or fats). This is due to their material diversity, since they contain alkaloids, fatty acids, glucosinolates, terpenoids or cyanogenic glycosides, among others. Likewise, they are used as ornamental plants.

Many of its species are characterized by having a milky or colorful latex. This is produced in multicellular laticifers, often being a toxic latex.

characteristics

Shapes

They can develop grasses, shrubs, trees, vines and lianas, sometimes fleshy and cactiform. A varied architectural growth pattern is characteristic of arborescent species.

Leaves

They are compound webbed or simple stipules (these can be transformed into spines or glands), alternate leaves (mostly) and opposite.

Inflorescence

Terminals or axillary, also finding cauliflowers or ramifloras. The genus Euphorbia is characterized by presenting a cytate-like inflorescence. This consists of an involucre with varied glands on the edge that contain numerous staminate flowers, which contain stamens without pistils; thus forming a cup-shaped structure.

flowers

They are unisexual, which indicates that they can be monoecious or dioecious plants, with three sepals of 5-6 and 5 or 6 simple petals; in some species they are absent and in others they are not very showy.

Stamen flowers: there are genera with overlapping sepals, this means that they have external and internal sepals; As well as genera with valvated sepals, which means that the sepals touch edge to edge along their entire length, but without overlapping.

Now, regarding its androecium, it frequently has 5 to 10 stamens (there are cases in which the stamens are reduced to 1 and others increased to 200 or more), of the filamentous type (usually fused), free or welded..

Pistillate flowers: this type of flower has imbricate sepals, sometimes being foliose (with leaves). In relation to the stamen flowers, the pistillate flowers have reduced petals, their gynoecium is gamocarpellar, with a super ovary made up of 3 welded carpels and 3 locules (1 or 2 ovules each), usually with 3 whole styles, bifidium or multifidios. Its placentation is axial.

Fruit

Most of these plants have schizocarp-type fruits, however, berries or drupes can also be found.

Seeds

The carpels are leaves that are modified, which form the female reproductive part of the flower of each plant. Now, in this case, each carpel has one or two seeds with an external integument, with or without endosperm. Your embryo can be straight or curved.

Taxonomy

The Euphorbiaceae family is made up of 227 genera and 6487 species, of which 6482 species exist today and 5 are extinct, representing one of the most varied families of the Magnoliophytas.

It is important to note that recent molecular studies indicate the division of Euphorbiaceae into several families such as: Astrocasia, Amanoa, Breynia, Croiatia, Discocarpus, Didymocisthus, Hieronyma, Jablonskia, Meineckia, Margaritaria, Phyllantus, Phyllanoa and Richeria. The other genera are conserved in Euphorbiaceae.

In turn, the Euphorbiaceae also have 5 subfamilies: Acalyphoideae, Oldfieldioideae, Crotonoideae, Phyllanthoideae and Euphorbiodeae.

Species belonging to the subfamily Acalyphoideae. Source: pixabay.com

It is a family with a high number of taxa, so its organization becomes more complex (family delimitation, subfamily composition and infrageneric organization).

For this reason, constant hierarchical changes are observed over the years. However, this disorganization has diminished thanks to recent studies focused on reordering this hierarchy.

Its taxonomic description is as follows:

-Kingdom: Plantae

-Filo: Tracheophyta

-Class: Magnoliopsida

-Order: Malpighiales

-Family: Euphorbiaceae

Habitat and distribution

Because they are such a diverse family, they are found in a wide variety of habitats, mainly rainforests, seasonal forests, and deserts.

Thus, they are plants with a very wide distribution that are found in tropical, subtropical and temperate zones of both hemispheres. The Amazon rainforest is one of the areas with the greatest endemism.

These plants develop better at low altitudes, however, there are reports in which the presence of some species of this family is indicated at altitudes of 4000 meters above sea level. Most of these species can be found in tropical America and Africa.

Genera and species

Most important genres

Within the Euphorbiaceae it is worth mentioning the following genera: Acalypha (431 existing spp.), Alchornea (50 existing spp.), Croton (1188 existing spp.), Euphorbia (2018 existing spp.), Hevea (10 existing spp.), Jatropha (existing 175 spp.), Macaranga (308 existing spp.), Manihot (131 existing spp.), Mercurialis (13 existing spp.), Ricinus (1 existing spp.), Tragia (153 existing spp.).

Species of the genus Jatropha. Source: pixabay.com

Most outstanding species

Alchornea glandulosa

Known as blackberry, guazú wallflower and milkweed, it has alternating simple leaves. It is a timber tree, 18 meters or more in height, being abundant in open and flooded forests.

Its most frequent uses include the production of packaging and saddlery. Its usefulness as a medicinal plant is also common, being support for the treatment of rheumatism and muscle pain.

Croton draco

It is a plant from 2 to 18 meters high that can develop as a tree or shrub. Its leaves range from 8 to 28 cm long and 5 to 18 cm wide, being ovate or ovate-deltoid. It has a bisexual inflorescence, a raceme 8 to 50 cm long and fruits 5 to 7 mm long. This type of plant is usually found in humid forests.

Its importance lies in the capacity it has as a nitrogen fixer and its medicinal properties.

The variety «bull's blood», named for its characteristic blood color, is widely used for the preparation of natural medicine by the natives and urban populations of South America and Central America.

Croton draco Schltdl. Source: pixabay.com

Euphorbia pulcherrima

Also known as "poinsettia" or "poinsettia", as it blooms at Christmas time. It has dark, velvety green leaves with serrated edges. It also has other colored leaves (bracts) that look like white, red, yellow or pink petals.

It is a native species of Central America widely used in popular medicine. For example, for the preparation of a poultice and for the treatment of various skin diseases.

Euphorbia pulcherrima Willd. ex Klotzsch. Known as poinsettia or poinsettia. Source: pixabay.com

Hevea brasiliensis

Commonly called "rubber tree", it has a height between 20 to 30 meters. It is characterized by its trifoliate leaves and its flowers are small and gathered to form a cluster. Its fruits are capsule type and it develops content of seeds rich in oil.

One of its most striking characteristics is its white or yellowish latex, which contains 30 to 36% hydrocarbon, 1.5% protein, 0.5% ash, 0.5% quebrachitol and 2% resin; this is abundant up to 25 years, being widely used to make rubber.

Rubber tree. Source: pixabay.com

Manihot esculenta

It is commonly known as cassava, yucca, cassava, guacamote or Manec, and it is widely cultivated in the tropics as a food plant. There are around 6000 varieties, each with peculiarities.

Regarding its characteristics, it is a perennial plant that has male and female flowers (thus being a monoecious plant). These flowers have colors that vary from purple to yellow. Its pollination is cross, with the help of insects. Its fruit is dehiscent type (which can open spontaneously), with small, oval seeds.

It is a perennial shrub, with large, webbed leaves which are used as forage, and has edible roots.

This species is of great interest, since it has a high production of flours with a high percentage of proteins. The stem is used for its vegetative propagation, its leaves to produce flour and its roots for fresh consumption.

Likewise, the ground leaf is used in the medicinal field, for the prevention of cancer, diabetes, cardiovascular or stomach disorders among others. It stands out for its high percentage of protein, vitamins, amino acids, iron, zinc, phosphorus and carbohydrates.

Manihot esculenta (yucca). Source: pixabay.com

Mercurialis annua

Its name annua is derived from the Latin annuus which means annual, named for its biological cycle that goes from year to year. It is characterized by being dioecious, somewhat pubescent, with a single erect stem of the herbaceous type of 30 to 70 cm, with opposite, ovate leaves and male flowers gathered in spike-like inflorescences.

It grows in humid soils at approximately 1700 meters above sea level. It is used as a medicinal plant after being processed.

Ricinus communis

Known as Castor bean, spurge or fig. This species is characterized by being a shrubby plant, with a warm climate, with a thick and woody stem; with large purple palmate leaves and flowers arranged in large inflorescences. It has globular trilobed fruits.

In relation to its use, this plant is used to make castor oil, by pressing and heating the seeds. This procedure is done to destroy ricin, which is severely toxic.

It is related to the manufacture of industrial products, such as varnishes, paints or lubricants, among others. It is also used in gardening, for its foliage.

Ricinus communis L. Source: pixabay.com

References

1. Bittner, M., Alarcón, J., Aqueveque, P., Becerra, J., Hernández, V., Hoeneisen, M., and Silva, M. 2001. Chemical study of species of the Euphorbiaceae family in Chile. Bulletin of the Chilean Society of Chemistry, 46 (4), 419-431
2. Catalog of Life: 2019 Annual Checklist. 2019. Euphorbiaceae. Taken from: catalogueoflife.org
3. Carmona J., Gil R. and Rodríguez M. 2008. Taxonomic, morphological and ethnobotanical description of 26 common herbs that grow in the city of Mérida - Venezuela. Anthropological Bulletin Universidad de Los Andes, Mérida, Venezuela. 26 (73): 113-129.

4. Hussain, F., Shah, SM, Badshah, L., and Durrani, MJ 2015. Diversity and ecological characteristics of flora of Mastuj valley, district Chitral, Hindukush range, Pakistan. Pak. J. Bot. 47 (2): 495-510.
5. Murillo J. 2004. The Euphorbiaceae of Colombia. Institute of Natural Sciences, National University of Colombia, section 7495, Bogotá, DC, Colombia. Colombian Biota 5 (2): 183-200.
6. Radcliffe-Smith, A. 2018. A review of the family Euphorbiaceae. In Naturally Occurring Phorbol Esters CRC Press. P. 63-85.

7. Schmidt, J. 2018. Biosynthetic and chemosystematic aspects of the Euphorbiaceae and Thymelaeaceae. In Naturally occurring phorbol esters. CRC Press. P. 87-106.

8. Steinmann V. 2002. Diversity and endemism of the Euphorbiaceae family in Mexico. Ecology Institute, Bajío Regional Center, Michoacán. Acta Botánica Mexicana 61: 61-93.
9. The Taxonomicon. (2004-2019). Taxon: Family Euphorbiaceae Juss. (1978). Taken from: taxonomicon.taxonomy.nl
10. Villalobos P. and Castellanos C. 1992. The Euphorbiaceae family as a source of vegetable oils for the technochemical industry. Superior Council of Scientific Investigations. Fats and oils magazine 43 (1). Taken from: fatyaceites.revistas.csic.es