What title is given to a magistrate with praefectural authority appointed by the Curia in emergency situations?

The title given to a magistrate with praefectural authority appointed by the Curia in emergency situations is correctly identified as Praefectus iure dicundo. This position was particularly significant as it allowed for legal administration and decision-making in urgent circumstances, reflecting the flexibility of the Roman political system to respond to crises.

The other titles listed refer to different roles within the Roman administration. The Praefectus urbi was primarily responsible for maintaining order in the city of Rome, focusing on public safety and administration rather than specifically appointed emergency situations. The Praefectus classis was in charge of the naval fleet, reflecting military command rather than judicial or governmental emergencies. Lastly, the Praefectus annonae was responsible for grain supply and price regulation, which, while crucial in times of relief or scarcity, does not pertain directly to the judiciary or magistracy in emergencies.