Elatostema section Weddellia series Xingyiensia L.D.Duan & D.H.Yin, ser. nov.

Diagnosis.

Mid-vein impressed, margin revolute, pistillate inflorescence peduncle dichotomously branched. Typus seriei: Elatostema xingyiense L.D. Duan & D.H. Yin.

Relationship.

The staminate capitula of the species is long peduncelate, as such this new series is closely related to ser. Elatostema Sublinearia W.T. Wang (Wang 1980). It also has similarity to ser. Elatostema Melanocarpa W.T. Wang with its achene fawn, ovoid, longitudinally 4(-5)-ribbed and tuberculate (Wang 2013). However, the new series differs from these two series with regards to the following features: leaf mid-vein impressed, the margin revolute (compared to the mid-vein flat and margin flat in ser. Elatostema Melanocarpa and ser. Elatostema Sublinearia); pistillate inflorescence peduncle dichotomously branched (compared to the peduncle not dichotomously branched in ser. Elatostema Melanocarpa and ser. Elatostema Sublinearia) (Table 1).