The type specimen was collected at the edge of Chittering Lake in Western Australia, where it was found growing on Melaleuca rhaphiophylla and Eucalyptus rudis.

[1] In 2013, Ulf Arup and colleagues transferred the taxon was to the newly circumscribed genus Kaernefia, in which it is the type species.

[4] Kaernefia kaernefeltii is characterised by a subtle and underdeveloped thallus, typically consisting of minute granules, warts, or granular-isidia formations.

This thallus may appear orange, greenish-orange, or brownish-orange and occasionally presents large, reddish apothecia, which can be either sparsely scattered or densely aggregated.

The thalline margin is quite thick, varying from zeorine to biatorine in form, and is often pruinose with a whitish tone, occasionally eroded, displaying colours ranging from rose to rose-yellow or greenish in shaded areas.

The lichen contains several chemical compounds, including parietin as a major component, O-methylvioxanthin, fallacinal, teloschistin, and trace amounts of atranorin.

[1] Kaernefia kaernefeltii has certain resemblances to the Northern Hemisphere's epiphytic species, Caloplaca herbidella, particularly in its isidia-like formations.

Another key difference lies in the oil cells within the paraphyses of K. kaernefeltii, which are broadened and centrally located, a trait not observed in C. herbidella.