SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b11aab652bb95ef2dafe3e36b4ced04969fb57cf565cc1c3dd6106194797775c' 
  AND token = 'oRvQiAJbzm0NIKYz8yp8UHqz6FzGDw0yvFwbZ+P/Y6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00071

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}