Orange-black Milkweed Bug

Size about 12mm. Found in mangrove/open eucalypt forest habitat. This species is commonly identified as Spilostethus. I found a picture representation with an identical doral pattern/drawing (see Identical drawing points at speciation. https://hiveminer.com/Tags/lygaeidae,seed/Interesting). I had assumed that this was a highly variable taxonomic group and am a bit surprised to find some consistency but no proper identification key. Maybe some expert know.