What is "idiothamnus"

Idiothamnus is a genus of South American flowering plants in the sunflower family.

1. Idiothamnus clavisetus (V.M.Badillo) R.M.King & H.Rob. - Venezuela
2. Idiothamnus lilloi (B.L.Rob.) R.M.King & H.Rob. - Argentina ( Salta + Tucumán)
3. Idiothamnus orgyaloides (B.L.Rob.) R.M.King & H.Rob. - Peru
4. Idiothamnus pseudorgyalis R.M.King & H.Rob. - Distrito Federal do Brasil, Rio de Janeiro