Rubia is the type genus of the Rubiaceae family of flowering plants, which also contains coffee. It contains around 80 species of perennial scrambling or climbing herbs and subshrubs native to the Old World. The genus and its best-known species are commonly known as madder, e.g. Rubia tinctorum, Rubia peregrina, and Rubia cordifolia.
Polygonum is a genus of about 130 species of flowering plants in the buckwheat and knotweed family Polygonaceae. Common names include knotweed and knotgrass. In the Middle English glossary of herbs Alphita, it was known as ars-smerte. There have been various opinions about how broadly the genus should be defined. For example, buckwheat has sometimes been included in the genus as Polygonum fagopyrum. Former genera such as Polygonella have been subsumed into Polygonum; other genera have been split off.
Galium spurium, the stickwilly or false cleavers, is a plant species of the Rubiaceae. It is widespread across Europe, Asia, Africa and Canada, and is naturalized in Australia. It is considered a noxious weed in many places.
Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species.
Crucianella is a genus of flowering plants in the family Rubiaceae. The species are annual herbs found from the Mediterranean to Central Asia and the Arabian Peninsula. One species is naturalized in northern California, southern Oregon, and Idaho.
Jurinea is a genus of flowering plants in the family Asteraceae.
Plocama is a genus of flowering plants in the family Rubiaceae. It was described by William Aiton in 1789. It is distributed from the Canary Islands to northwestern India.
Cynanchica, commonly known as woodruff, is a genus of flowering plants in the family Rubiaceae. It contains 73 species and has a wide distribution area from Europe, northern Africa, the Middle East and central Asia. The genus was erected in 2020 to accommodate species split from the genus Asperula.
Crepidinae is a subtribe of Cichorieae in the family Asteraceae.
Asperula tetraphylla is a species of flowering plant in the family Rubiaceae. It was first described in 2009 and is endemic to South Australia.
Eremogone is a genus of flowering plants in the family Caryophyllaceae, native to western North America, northern Asia, eastern Europe and northeastern Africa. Attempts to resolve taxonomic relationships within the Caryophyllaceae have resulted in the enlargement of Eremogone with species from other genera.
Thliphthisa is a genus of flowering plants in family Rubiaceae. It includes 22 species which range from southern Europe to Turkey, Cyprus, Syria, and Iran.
