This larval tube-anemone (right) has already begun fishing for food with the tentacles it will use as an adult. The dark stomach suggests it is already a successful hunter even as it is about a centimetre in size.

An earlier stage of the larval tube-anemone, this specimen (left) looks as if it has a smiling face inside. The common types of sea-anemones spend little, if any, time in the plankton, compared to these tube-anemones which spend much longer and appear to feed while there too.

Photo credit: CoML