SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0264011fa19b6ae4008fd4aef58c75ed0980a4ac4c8cfc34593ba4c21fe9d819' 
  AND token = '1qcq7CcMaHnbjTGD/wdgAp6g3ijqfxIBXYLxJlHJj3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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