Tubed Cardinalfish

Found in small schools usually amongst the spines of either sea urchins or the crown-of-thorns sea star, over outer lagoons and sheltered coastal reefs.
These cardinalfish can rapidly change colour from stripes to dark brown with a couple of white spots.

Males incubate their eggs inside their mouths, as the egg masses increase in size they can be found with wide open mouths where they shift the eggs around to aerate the egg masses.