SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cd426511c9259841ff5be244dc8205ce661c28b758b40da0d47bfc87cc2b643' 
  AND token = 'h8YtOdXDsOVd+OdZahQa8agSPaJYyWrwS0fuwhIADr0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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