SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87f183fa42974f2a69c92ca4567ba014a3436724c6329e121c85a6e8159588d1' 
  AND token = 'CzV+9RKrUX9W8xZsTm9Su8sdjlTW+OunHtRw9MvSoJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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