Similar to C. crockerae but tends to be smaller and slightly narrower and has a paler more yellowish pronotum. Close also to C. testacea but it lacks the more obvious ribs on the elytra which distinguish that species.

The Eyre Peninsula specimens previously referred to this name have now been re-identified as C. crockerae (q.v.). Images illustrating bud mimicry are provided under that species and this phenomenon is applicable also to C. subtestacea and other members of the C. testacea group.

(Barker 1983, p.150) questioned the locality for a single male of this species at the SA Museum designated from 'S. Aust.'. Later, in Barker 2006a, he lists 'Black Hill' as the only SA location for the species, and this corresponds to specimens in the SA Museum from 10 km N of Black Hill township in the Murray Mallee. Given the propensity for intergradation in this complex, the identities of museum specimens supporting SA occurrences of C. subtestacea (and C. testacea) should be treated as provisional until they can be investigated further.