Take a dive in the waters surrounding Pulau Hantu, a small island off the west coast of Singapore, and you may reemerge feeling unimpressed. Visibility around the island rarely tops three to four metres, and plentiful algae tint the water a vivid green.
For macro photographers like Katherine Lu, however, Hantu is a hidden gem. The island harbours a little-known reef that's teeming with tiny marine life – and among its most remarkable inhabitants are the local sea slugs.
"Pulau Hantu means 'Ghost Island' in Malay," Lu told WetPixel.
"For the regulars who dive there, it never ceases to amaze what we might find."
The "Pikachu" sea slug, a nudibranch in the genus Thecacera | Katheriine Hu/WetPixelSakuraeolis kirembosa | Katherine Lu/WetPixelTenellia sibogae | Katherine Lu/WetpixelPlacida sp | Katherine Lu/WetPixelBornella anguilla | Katherine Lu/WetPixelA nudibranch in the genus Stilliger | Katherine Lu/WetPixelTwo Tambja sea slugs form "egg roses" atop a stony coral | Katherine Lu/WetPixelPhyllodesmium sp | Katherine Lu/WetPixel"Doto greenamyeri aka the 'Donut Doto'. This photogenic nudibranch is highly sought out by photographers," says Lu. "This year we discovered it for the very first time (here with eggs) and it became a new Singapore record. It has been regularly sighted over the past several months so hopefully it is here to stay." | Katherine Lu/WetPixel"Shaun the sheep" Costasiella sp. Measuring just two to three millimetres, this tiny sea slug has the ability to absorb chloroplasts from the algae it feeds on. This allows photosynthesis to occur in the animal's body | Katherine Lu/WetPixel
