Aggregation of
D. setosum
in day time and coral damage. A group of
D. setosum
on a colony of
P. carnosus
of 80 cm in the longest horizontal dimension (a); a colony of
P.
carnosus
(35 cm in the longest horizontal dimension) with a
D. setosum
on the top (b); a fresh lesion (indicated by a white arrow) was revealed from the same coral colony
when the sea urchin was driven down to the seabed using a steel rod (c)