I flipped not my lid, but a rock on a rock platform this morning on the coast in northern New South Wales, for International Rock-flipping Day (this year 11 September 2011). Here’s what was underneath.
I had to move this sipunculid worm, the peanut worm (Phascolosoma noduliferum), as the tide was sloshing it about, making it difficult to photograph. This one is about 3 cm in length.
It’s actually a bit scrunched up above. I’ve seen them get really thin really fast. This one then stretched out and quickly everted a section at the mouth end, adding a good centimetre. Apparently this part, technically called an ‘introvert’, has rows of little hooks. There’s a mouth at the end.
Peanut worms hoover up sand, absorbing the organic material in it. I put it back in the water quickly as I didn’t want to disturb it too much.
Another relatively large thing revealed by moving the rock was this sea cucumber (Australostichopus mollis?) …
There are some really fabulous photos of many spectacular sea cucumbers here. They make this one look very ordinary. Sea cucumbers also hoover sandy bottoms, and are often found under rocks or ledges as protection for their very soft bodies.
Lastly, sharing the sand with these was (I think) a blenny – but that’s as far as my ID goes, I’m afraid. I’ve looked in various books and on the net, but I’m not confident of getting further than that. You can see sensory ‘feelers’ (I’m sure there is a technical term for them) on its nose in the first shot. The calcareous worm tubes above it are those of Galeolaria caespitosa.
Of course, I oh so carefully put the peanut worm back and ever so gently lowered the rock back into the same position. Hopefully these sort of disturbances don’t affect the animals too much. But I always feel slightly guilty for worrying them.