Caucalis is a monotypic genus of flowering plants in the carrot family (Apiaceae), order Apiales. Its sole species, Caucalis platycarpos, is an annual herb native to Europe, North Africa, and the Middle East as far east as Iran. The plant grows up to 40 centimetres tall with trailing stems and leaves that are highly divided into many small leaflets. Flowers are produced in umbels of two to five, each with white or pink petals. The fruit is an oblong capsule covered with numerous hooked spines — a burr-like structure that gives the plant its common names: carrot bur parsley, small bur-parsley, and burr parsley. The genus is placed within Apiaceae, a family known for its aromatic and often economically important members, though Caucalis itself is primarily known as an arable weed.
Distribution
Caucalis is native to Europe, North Africa, and the Middle East as far east as Iran. Within Europe it is distributed across most of central and southern Europe including almost the entire Iberian Peninsula, and extends into southwest Asia.
Ecology
Caucalis platycarpos is a nitrophilous species found in crop fields, fallows, and nitrophilous grasslands. It prefers basic (alkaline) substrates and grows at altitudes of 100–1000 metres, occasionally up to 1600 metres. Flowering takes place from March to June (sometimes into July), with fruiting from May through August.
Taxonomy
Caucalis is a monotypic genus within the family Apiaceae (order Apiales), containing only the species Caucalis platycarpos. The genus name has no recorded authorship in GBIF, though it is a long-established segregate genus within the carrot family. GBIF records exactly one accepted descendant.
