SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce1803a4fd27f03a064d4ccc0172f09d4ddcbfdb1a9e7f90178b3aab8780fb30' 
  AND token = 'fHwLZz9fqumzwXw2Pgbhje2cM+xdnSHANViMT6Yrgus=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}