The Insiders, by Qing Lin, China (Under Water)
The bulbous tips of the aptly named magnificent anemone’s tentacles contain cells that sting most fish. But the clown anemonefish goes unharmed thanks to mucus secreted over its skin, which tricks the anemone into thinking it is brushing against itself.
Both species benefit. The anemonefish gains protection from its predators, which daren’t risk being stung, and it also feeds on parasites and debris among the tentacles; at the same time, it improves water circulation (fanning its fins as it swims), scares away the anemone’s predators, and may even lure in prey for it.
While diving in Lembeh Strait in North Sulawesi, Indonesia, Qing noticed something strange about this particular cohabiting group. Each anemonefish had an extra pair of eyes inside its mouth – those of a parasitic isopod (a crustacean related to woodlice).
An isopod enters a fish as a larva, via its gills, moves to the fish’s mouth and attaches with its legs to the base of the tongue.
As the parasite sucks its host’s blood, the tongue withers, leaving the isopod attached in its place, where it may remain for several years.
With great patience and a little luck – the fish darted around unpredictably as they usually do – Qing captured these three curious individuals momentarily lined up, eyes front, mouths open and parasites peeping out.
- Taken with a Canon EOS 5D Mark III & 100mm f2.8 lens; 1/200 sec at f25; ISO 320; Sea & Sea housing; two Inon strobes.