From editor or global species database
Diagnosis Test thin-plated; weakly imbricate especially adapically; interambulacral plates with primary tubercle and smaller adradial secondary tubercle on ambital plates. On adoral plates, primary and flanking secondary tubercles are almost the same size, while adapically a single large primary tubercle dominates. Spines nonverticillate but with a fine, transverse, anatomising sculpture. [details]
Etymology From the Latin australis (= southern) & -diadema [common suffix for diadematoids] [details]
Fossil range Aptian [details]