85. Calendula Linnaeus, Sp. Pl. 2: 921. 1753; Gen. Pl. ed. 5, 393. 1754.
Pot marigold [Latin calends, first day of the month, and -ula, tendency; perhaps meaning "through the months" and alluding to ± year-round flowering]
John L. Strother
Annuals, perennials [subshrubs], 5–50(–70+) cm. Stems procumbent to erect, glabrous or arachnose and/or stipitate-glandular. Leaves sessile or petiolate; blades elliptic, obovate, or oblong to oblanceolate, spatulate, or linear (bases sometimes clasping), margins entire or denticulate, faces sparsely arachnose and/or stipitate-glandular. Heads borne singly. Involucres campanulate to hemispheric or broader, 10–30+ mm diam. Phyllaries 13–40+ in 2+ series, lanceolate to lance-linear. Receptacles flat. Ray florets 13–50(–100+) in 1–3+ series; corollas yellow to orange, laminae linear to oblanceolate. Disc florets 20–60(–150+), functionally staminate; corollas yellow, reddish, or purplish, tubes shorter than ± campanulate throats. Cypselae arcuate to ± coiled (usually some beaked, some 2–3-winged, some both beaked and winged), abaxial faces usually tuberculate and/or transversely ridged. x = 11.
Species 15 or fewer (2 in the flora): introduced; Macaronesia, Mediterranean Europe, Near East, North Africa; widely cultivated, sometimes escaping and/or persisting.
Heyn, C. C., O. Dagan, and B. Nachman. 1974. The annual Calendula species: Taxonomy and relationships. Israel J. Bot. 23: 169–201.