SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8183af0bbbb599685269db98d5dd7d7150dcfeb6bddeb625b40fbe65767c453f' 
  AND token = '0Qq4WOTGt9uTro9HMgv0eHnjeT11eqpvel/RrGWIZEE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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