SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1aaf0468170c8c531340cbfb20f1989351ec28eee6e5213c1443c87e1d40cf13' 
  AND token = '5QEujkBUvYj/jp2OR6hA97RUiKuFvqELqT1wdygKQkc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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