MACRO- and micromorphological characteristics of cypsela in 13
species and one subspecies representing genera: Carthamus L.,
Centaurea L. Cichorium L., Cirsium Mill., Crepis L., Lactuca L.,
Picris L., Reichardia Roth, and Sonchus L.; belonging to the two tribes
Cardueae and Cichorieae of the Asteraceae were examined under
stereomicroscopy and scanning electron microscopy (SEM). The
cypsela macromorphological features including; cypsela length
measurements, colour, shape, surface texture and the number of ribs
when present as well as the abscission scar characteristics and details
of the surface, microsculpture peculiarities were investigated. The
cypsela length and colour presented a minor taxonomic value.
However, the other remaining features were proved to be primarily
diagnostic at the species level and sometimes at the genus level but not
distinctive for any of the two tribes. In addition, these features were
very useful in the precise technical identification of the examined
cypselae. An identification key for the studied taxa, based on the
investigated aspects, was presented.