3 Euros Doridid Nudibranch

Austria's 3 euro "Tierwelt" animal series has run since 2018, issuing a new creature annually at a price point designed to pull in collectors who wouldn't otherwise buy bullion or commemoratives. The doridid nudibranch continues that strategy — an invertebrate that most buyers will have never encountered in the wild, printed in vivid color on the reverse to compensate for the format's lack of precious metal content.

Doridids are shell-less marine mollusks whose toxic chemistry comes entirely from the sponges they consume — they manufacture nothing themselves.