and the early type galaxies from @Crocker2012. Again, the upper limits from the post-starburst targets are consistent with their quiescent SFRs, though the limits on H02 are higher than most of the quiescent comparison sample.

As discussed in §\[sec:sfr\], the SFR for H02 is uncertain, with various tracers estimating $\sim 0.09-1$ M$_\sun$yr$^{-1}$. In Figures \[fig:hcn\] and \[fig:hco\_plus\] we see that even at a SFR of $1$ M$_\sun$yr$^{-1}$, H02 still has a high $L^{\prime}($CO$)$ for its SFR, and yet a $L^{\prime}($HCN$)$ and $L^{\prime}($HCO$^+)$ consistent with the relation followed by the comparison galaxies.

In @French2015, we proposed several scenarios for explaining the discrepancy between the high CO luminosity and the low SFR aside from a low CO-traced star formation efficiency. Many are now disfavored given the consistency between the HCN luminosity and SFR. The observed discrepancy is not likely driven by un-accounted for dust extinction or significant low-mass star formation (a very bottom-heavy IMF) that is hidden from our SFR tracers. It is also improbable that significant star formation is missed in the aperture correction of the SFRs from the 3 (2.7-3.2 kpc) SDSS fibers (see discussion in §\[sec:sfr\]). The range of SFRs inferred from various tracers implies a large range of 