Piper (genus)
Piper, the pepper plants or pepper vines (a term used for certain Clematis
Clematis is a genus of about 300 species within the buttercup family Ranunculaceae. Their garden hybrids have been popular among gardeners beginning with Clematis × jackmanii, a garden standby since 1862; more hybrid cultivars are being produced constantly. They are mainly of Chinese and Japanese...

in older times), are an economically and ecologically important genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

The Piperaceae, also known as the pepper family, is a large family of flowering plants. The group contains roughly 3,610 currently accepted species in five genera. The vast majority of peppers can be found within the two main genera: Piper and Peperomia .Members of the Piperaceae may be small...

. It contains about 1,000-2,000 species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of shrubs, herbs, and liana
A liana is any of various long-stemmed, woody vines that are rooted in the soil at ground level and use trees, as well as other means of vertical support, to climb up to the canopy to get access to well-lit areas of the forest. Lianas are especially characteristic of tropical moist deciduous...

s, many of which are keystone species
Keystone species
A keystone species is a species that has a disproportionately large effect on its environment relative to its abundance. Such species play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and...

 in their native habitat The diversification of this taxon is of interest to understanding the evolution of plants.

Pepper plants belong to the magnoliids, which are angiosperms but neither monocots nor eudicots.