Round-fruited Hemlock (Conium sphaerocarpum)

Silhouette: T. Michael Keesey / License

Conium sphaerocarpum: Rounded-Seed Hemlock of South Africa

Characterized by its distinctively rounded seed structures, Conium sphaerocarpum populates the rocky and montane landscapes of South Africa's Western and Northern Cape provinces.

This wild species was described by botanists Olive Mary Hilliard and Brian Laurence Burtt in 1985. It belongs to the family Apiaceae and represents a significant component of the local poisonous flora.

Taxonomy

∟ царство Plantae
∟ division Tracheophytes (Vascular Plants)
∟ subdivision Spermatophytes (Seed plants)
∟ Angiosperms
∟ mesangiosperms (Core angiosperms)
∟ eudicots
∟ asterids
∟ order Apiales
∟ family Apiaceae
∟ genus Conium (Hemlock)
∟ species Conium sphaerocarpum (Round-fruited Hemlock)

Morphology

The plant features upright, ribbed stems that often branch out in the upper portions.

Its leaves are finely divided into multiple small segments, producing a delicate, feathery texture typical of the Apiaceae family. The inflorescence consists of terminal compound umbels bearing numerous tiny white flowers.

Unlike some of its close relatives, this species develops notably spherical fruits, which serve as the primary diagnostic feature for botanical identification.

Flowering season

Southern Hemisphere summer, typically from December to February

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Feb

Mar

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May

Jun

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Oct

Name

Dec

Applications

This species contains dangerous levels of piperidine alkaloids, rendering it completely unsuitable for human consumption or garden cultivation.

Contact with the plant or accidental ingestion can lead to severe poisoning in domestic animals and wildlife. It is studied mainly by botanists and veterinary scientists to map toxic plant distributions in pastures.

Interesting facts

The naming of this species directly reflects its physical appearance and the history of South African botanical research.

Descriptive Epithet: The name sphaerocarpum translates from Greek as "spherical fruit," pointing to its unique seed shape.
Pasture Hazard: Farmers in the Western Cape monitor this plant closely, as it can contaminate grazing land for sheep and cattle.
Burtt and Hilliard Partnership: This species was one of many documented during their intensive collaborative studies of the South African flora.

Geography of distribution

Western Cape
Northern Cape

Sources

Govaerts, R. et al. 2025. Conium sphaerocarpum in Kew Science Plants of the World Online. The Board of Trustees of the Royal Botanic Gardens, Kew.
Hilliard, O.M. & Burtt, B.L. 1985. Conium (Umbelliferae) in southern Africa. South African Journal of Botany 51(6): 465–474.