To better understand the taxonomy and phylogeny of the Anisopappinae and Athroismeae, the exine ultrastructure of two species of the two genera of that subtribe — Anisopappus chinensis Hook. & Arn. and Cardosoa athanasioides (Paiva & S. Ortiz) S. Ortiz & Paiva (both representing the types of the generic names) — were studied with transmission electron microscopy and scanning electron microscopy. As for other Asteroideae and Asteraceae, the existence of a mesoaperture intersecting the foot layer and the upper part of the endexine was established. The exines of both taxa have a Helianthoid pattern of structure, which supports the approaching of the Athroismeae to the Heliantheae s.l. but not to the Inuleae. There were no significant differences between the qualitative and quantitative characters of the two taxa, which support the inclusion of Cardosoa S. Ortiz & Paiva in the Anisopappinae and the consistency of the subtribe.