It appears to have pistils protruding from it that would indicate a female, not to mention there is a whole bunch of pistils growing next to it, so to me it is clearly a female.
However, it does look big, and it's pistils are brown whereas the other pistils visible nearby are still white, so I think maybe that female calyx has been pollinated which if so would explain it 'bigness' if it is swollen with a developing seed and also explain the pistils having turned brown indicating pollination may have occurred.