An adult. Spotted by @millamuck
Small one under a rock.
A smallish one tucked into some algae quite shallow.
4 juveniles on blue sponge from 2 to 3mm
4m depth
8 degrees
Searched all over but just one at the good reef wall. Might even be the same individual I saw a month ago! Now even more spectacular fully grown.
I noticed when a fish attacked it or I nudged it, the slug would extend all its cerata out into a spike ball.
~3.5 cm long
~3 m subtidal