Coleostephus is a small genus of flowering plants in the daisy family (Asteraceae), order Asterales, first described by the French botanist Alexandre Henri Gabriel de Cassini in 1826 (published in Dictionnaire des Sciences Naturelles, vol. 41). The genus comprises just a handful of species — Wikipedia recognizes three: Coleostephus multicaulis, Coleostephus myconis, and Coleostephus paludosus — native to the western Mediterranean basin, with ranges spanning the Iberian Peninsula, southern France (including Corsica), Italy (including Sardinia and Sicily), the Balkans, and North Africa (Morocco, Algeria, Tunisia, Libya).
The best-documented member, Coleostephus myconis (corn marigold), is an annual herbaceous plant typical of the genus's growth form: it reaches 20–50 cm in height, with an erect, usually branched stem that is glabrous to hairy. Lower leaves are spatulate while the median leaves are lanceolate, dentate, and more or less clasp the stem (amplexicaul). Flower heads are solitary and terminal, orange-yellow, and about 2–3 cm wide, blooming from April to July. Plants in the genus typically grow in grassy fields at low-to-moderate elevations (0–800 m) within their native Mediterranean range. C. myconis has also been introduced to southern Brazil, Argentina, and Uruguay, where it behaves as an invasive weed of disturbed and agricultural ground — a pattern consistent with the genus's association with open, grassy habitats.
Distribution
Species of Coleostephus are native to the western Mediterranean basin, including the Iberian Peninsula, southern France and Corsica, Italy with Sardinia and Sicily, the Balkans, and North Africa (Morocco, Algeria, Tunisia, Libya). Coleostephus myconis has additionally been introduced to southern Brazil, Argentina, and Uruguay, where it is considered invasive.
Ecology
Coleostephus myconis typically grows in grassy fields at altitudes of 0–800 m within its native Mediterranean range, flowering from April to July.
Taxonomy Notes
The genus Coleostephus was described by Cassini in 1826 (Dictionnaire des Sciences Naturelles, vol. 41, p. 43) and placed in family Asteraceae, order Asterales. GBIF's backbone taxonomy lists 5 descendant taxa under the accepted genus record; Wikipedia names three constituent species (C. multicaulis, C. myconis, C. paludosus).
