SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7127ff37f550ec1cd9c6be074150185665e9209a80357519271d167ca7ee3995' 
  AND token = '6xK9IZZ7ZgLQUvxpRmtA7N5zn1/ojaU5jythDYhq1io=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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