CREATE TABLE table_49333 ("Name" TEXT, "Built" TEXT, "Listed" TEXT, "Location" TEXT, "County" TEXT)

what's the listing date for the verdigris creek bridge in royal of antelope county?
SELECT "Listed" FROM table_49333 WHERE "County" = 'antelope' AND "Location" = 'royal' AND "Name" = 'verdigris creek bridge'
SELECT "Listed" FROM "table_49333" WHERE "County" = 'antelope' AND "Location" = 'royal' AND "Name" = 'verdigris creek bridge'