Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56d5c6a6d9803e875717ea4ee5530ba2240e8d755423b820d20be6bd4739b559' 
  AND token = 'nHFy69XJ/OktN4xOwsYmY3b/7WiVPHNu8JW0alsjQzk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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