Chthonocephalus tomentellus is an annual herb in the family Asteraceae

Asteraceae

The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

. It is endemic to Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

, occurring in saline depressions. Yellow flowers are produced between August and November (late winter to late spring) in its native range.
The species was first formally described as Lachnothalamus tomentellus by botanist Ferdinand von Mueller

Ferdinand von Mueller

Baron Sir Ferdinand Jacob Heinrich von Mueller, KCMG was a German-Australian physician, geographer, and most notably, a botanist.-Early life:...

 in 1863 in Fragmenta Phytographiae Australiae

Fragmenta phytographiae Australiae

Fragmenta phytographiae Australiae is a series of papers authored by the Victorian Government botanist Ferdinand von Mueller in which he published many of his approximately 2000 descriptions of new taxa of Australian plants. The papers were issued in 94 parts between 1858 and 1882 and published in...

from a type specimen collected near to the mouth of the Murchison River.