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We report novel observational evidence on the evolutionary status oflithium-rich giant stars by combining asteroseismic and lithium abundance data.Comparing observations and models of the asteroseismic gravity-mode periodspacing $\Delta\Pi_{1}$, we find that super-Li-rich giants (SLR, A(Li)~$>3.2$~dex) are almost exclusively young red-clump (RC) stars. Depending on theexact phase of evolution, which requires more data to refine, SLR stars areeither (i) less than $\sim 2$~Myr or (ii) less than $\sim40$~Myr past the maincore helium flash (CHeF). Our observations set a strong upper limit for thetime of the inferred Li-enrichment phase of $< 40$~Myr post-CHeF, lendingsupport to the idea that lithium is produced around the time of the CHeF. Incontrast, the more evolved RC stars ($> 40$~Myr post-CHeF) generally have lowlithium abundances (A(Li)~$<1.0$~dex). Between the young, super-Li-rich phase,and the mostly old, Li-poor RC phase, there is an average reduction of lithiumby about 3 orders of magnitude. This Li-destruction may occur rapidly. We findthe situation to be less clear with stars having Li abundances between the twoextremes of super-Li-rich and Li-poor. This group, the `Li-rich' stars ($3.2>$~A(Li)~$> 1.0$~dex), shows a wide range of evolutionary states.

Tracking the evolution of lithium in giants using asteroseismology: Super-Li-rich stars are almost exclusively young red-clump stars