Boring sponges destructive to economically important Molluscan beds and coral reefs in Indian seas

Abstract

Systematics, descr'ption and distribution are given of 32 species of boring sponges from the Indian seas, the frequency of occurrence of which can vary from time to time as any one or more speci'js can at any lime cause an outburst creating severe havoc in the economically important molluscan and coral bedis and then disappear into a period of quiescent stage, while some others may continue to exhibit moderate incidence without causing any such deleterious effects. During the period of the present study only some species were moderately active an the Indian seas, and those, in the order of abundance, were Cliona celata, C. vastifica and C. carpenteri on chanks; C. vastifica and C. celata on pearl oysters; C. celata, C. vastifica and C. carpenteri on edible oysters; C. celata, Spirastrella cuspidifera, S. inconstans and S. aurivilli on corals. The present composition of boring sponge in the Indian seas is liliely to get altered in future, and such changes if any may be well affirmed by comparing with the observations presently reported. The boring pattern, damage caused to the shell, the modes of reproduction of the sponges, etc., are discussed. Some of the common measures adopted for controlling the boring sponges in different parts of the world are reviewed. Illustrations are provided for all the 32 species described.