Host galaxy properties provide strong constraints on the stellar progenitors of superluminous supernovae .
By comparing a sample of 16 low-redshift superluminous supernova hosts to a volume-limited galaxy population in the local Universe , we show that sub-solar metallicities seems to be a requirement .
All superluminous supernovae in hosts with high measured gas-phase metallicities are found to explode at large galactocentric radii , indicating that the metallicity at the explosion site is likely lower than the integrated host value .
We also confirm that high specific star-formation rates are a feature of superluminous supernova host galaxies , but interpret this as simply a consequence of the anti-correlation between gas-phase metallicity and specific star-formation rate and the requirement of on-going star formation to produce young , massive stars greater than \sim 10-20 M _ { \odot } .
Based on our sample , we propose an upper limit of \sim 0.5 \textnormal { Z } _ { \textnormal { \astrosun } } for forming superluminous supernova progenitors ( assuming an N2 metallicity diagnostic and a solar oxygen abundance of 8.69 ) .
Finally , we show that if magnetar powering is the source of the extreme luminosity then the required initial spins appear to be correlated with metallicity of the host galaxy .
This correlation needs further work , but if it holds it is a powerful link between the supernova parameters and nature of the progenitor population .