SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b765568eba38f59bdd5fda7568efeea3321fca845c8e98022fb4239e97ba3b9' 
  AND token = 'IRP0iehr71xKhXzvS1XA1zatdkGSdnu1a6w4g7V5o6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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