Moreover, pollen of Liabeae is prominently echinate and the exine has much broader columellae than in the Anthemoid pattern (Skvarla et al., 1977), which characterizes the pollen of Mutisioideae.

exine type is characterized by long spines with apical channels and an intricate layer of columellae under the tectum.

The pollen of Mutisieae and Stifftieae is psilate, microechinate, or echinate, with a compact ectosexine constituted by very thickly disposed columellae and a clearly columellate endosexine.

lophate in some Arctoteae, Barnadesioideae, Lactuceae, and Vernonieae); and (8) exine structure always densely columellate with stout columellae (vs.

Pollen microechinate or echinate, the ectosexine with columellae very thickly disposed (compact aspect), and the endosexine clearly columellate.

The infratectum is 0.8-1.2 [micro]m thick and comprises two distinct columellae layers separated by multiple, compact, internal tecta.

The columellae of the inner layer are aggregated under the spines and not swollen at the base.

The columellae of the inner layer are evenly-distributed across the grain and not swollen at the base.

The columellae are aggregated under lophae and not swollen at the base.

The columellae are evenly distributed and not swollen at the base.