Walking Dendro

Heteropsammia cochlea

Walking dendro is a small solitary coral native to the Indo-Pacific region, easily identified by its unique figure-eight shape when viewed from above. This coral, which can grow up to 2.5 cm across, is free-living and not attached to the sea floor. Its coloration ranges from yellowish to grayish or greenish, and its polyp tentacles are most visible at night. Walking dendro is commonly found on soft horizontal or gently sloping sandy bottoms, from shallow waters down to depths of 40 meters. It thrives in tropical and subtropical waters, from the eastern coasts of Africa to the Philippines, and from southern Japan to Australia and New Caledonia. This coral has an interesting life cycle, reproducing both sexually and asexually. It releases gametes into the water, where larvae develop in a planktonic stage before settling on a microgastropod shell. Walking dendro has a symbiotic relationship with a sipunculid worm, Aspidosiphon muelleri, which lives in an orifice at the coral's base. The worm's movement helps prevent the coral from being buried in sediment, making the coral dependent on the worm's presence. Walking dendro is classified as Least Concern by the IUCN and is relatively common in certain areas. Divers encountering this coral may notice its solitary nature and the small parasitic mussels, Lithophaga lessepsiana, that often accompany it.