The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with interpetiolar stipules and sympetalous actinomorphic flowers. The family contains about 13,500 species in about 620 genera, which makes it the fourth-largest angiosperm family. Rubiaceae has a cosmopolitan distribution; however, the largest species diversity is concentrated in the tropics and subtropics. Economically important genera include Coffea, the source of coffee, Cinchona, the source of the antimalarial alkaloid quinine, some dye plants, and ornamental cultivars.
Oldenlandiopsis (creeping-bluet) is a genus of flowering plants in the family Rubiaceae. It is monospecific, comprising only one species, Oldenlandiopsis callitrichoides. This species had previously been placed in Hedyotis or in Oldenlandia. It is native to the West Indies, southern Mexico, and Central America. It is naturalized elsewhere, including Florida, Hawaii, South America, and tropical Africa.
Houstonia (bluet) is a genus of plants in the family Rubiaceae. Many species were formerly classified, along with other genera since segregated elsewhere, in a more inclusive genus Hedyotis.
Oldenlandia is a genus of flowering plants in the family Rubiaceae. It is pantropical in distribution and has about 240 species. The type species for the genus is Oldenlandia corymbosa.
Hedyotis (starviolet) is a genus of flowering plants in the family Rubiaceae. Many species of this genus such as Hedyotis biflora, H. corymbosa and H. diffusa are well known medicinal plants. Hedyotis is native to tropical and subtropical Asia and to islands of the northwest Pacific. It comprises about 115 species. The type species for the genus is Hedyotis fruticosa.
Kadua is a genus of flowering plants in the family Rubiaceae. It comprises 29 species, all restricted to Polynesia. Twenty-two of these are endemic to the Hawaiian Islands. Some of the species are common at high elevation. Others are single-island endemics or very rare, and a few are probably extinct. Kadua affinis is widely distributed in Hawaii and is polymorphic. The type species for the genus is Kadua acuminata.
Arcytophyllum is a genus of flowering plants in the family Rubiaceae. The genus contains 18 species, distributed from New Mexico to Bolivia.
Astiella is a genus of flowering plants in the family Rubiaceae. It was described by Jovet (1941) as a monospecific, herbaceous genus, endemic to Madagascar. Later, 11 new species endemic to Madagascar were added to the genus.
Razafimandimbisonia is a genus of flowering plants in the family Rubiaceae. It is endemic to Madagascar.
Dimetia is a genus of flowering plants in the family Rubiaceae. The genus is found from the Indian subcontinent to south-central China and west and central Malesia.
Edrastima is a genus of flowering plants in the family Rubiaceae. The genus widespread and is found in Central and Eastern USA and the tropics and subtropics.
Exallage is a genus of flowering plants in the family Rubiaceae. The genus is found from tropical and subtropical Asia to the southwestern Pacific.
Hedyotis verticillaris is a plant belonging to the family Rubiaceae that is endemic to the higher altitude grasslands of the Nilgiris in southern India. Unlike many others members of the genus the stems of this species are underground and the leaves appear close to the ground forming rosettes and usually hold some water at the centre of the whorl of leaves. The flowers are produced on a stalk.
Carterella is a monotypic genus of flowering plants in the family Rubiaceae. The genus contains only one species, viz. Carterella alexanderae, which is endemic to Baja California Sur in Mexico. It grows on steep slopes in the mountains.
Thamnoldenlandia is a genus of plants in the Rubiaceae. It contains only one known species, Thamnoldenlandia ambovombensis, endemic to Madagascar.
Spermacoceae is a tribe of flowering plants in the family Rubiaceae and contains about 1346 species in 57 genera. Its representatives are found in the tropics and subtropics.
Debia is a genus of flowering plants in the family Rubiaceae. The genus is found from the Indian subcontinent to south-central China and the Philippines.
Involucrella is a genus of flowering plants in the family Rubiaceae. The genus is found from Northeast India to Hainan and Peninsular Malaysia and the Philippines.
Leptopetalum is a genus of flowering plants in the family Rubiaceae. The genus is widespread in tropical and subtropical Asia and the Pacific.
