Cota J. Gay
Cota is a segregate of Anthemis and encloses annual or perennial species with rigid receptacular scales and indistinctly ribbed, more or less compressed achenes that are rhombic in transverse section. In addition to morphological features, Cota has furthermore particular cytological, phytochemical and molecular traits (Lo Presti & al. 2010). It comprises 40 species (Oberprieler & al. 2007), mostly native to Europe, southwestern Asia and North Africa. One species, Cota tinctoria (L.) J. Gay (syn.: Anthemis tinctoria L.), is usually considered to be native in Belgium but this is questionable (it surely rather is an archaeophyte). It is mostly confined to man-made habitats and a large majority of the recent records is definitely non-native. It is a rather frequent grain alien, garden escape or is sometimes deliberately sown.
1 Ligular florets white. Annual or biennial === 2
1 Ligular florets yellow (rarely absent). Perennial (native) === Cota tinctoria
2 Acumen of receptacular scale ca. as long as the body. Achenes 8-10 striate on either side. Peduncle clavate in fruit === 1. C. altissima
2 Acumen of receptacular scale ca. ½ as long as the body. Achenes 2-3 striate on either side. Peduncle not clavate in fruit === 2. C. austriaca
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Oberprieler C., Himmelreich S. & Vogt R. (2007) A new subtribal classification of the tribe Anthemideae (Compositae). Willdenowia 37: 89-114.
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