Indian Journal of Marine Sciences Vol. 32(3), September 2003, pp. 237-239 Short Communication Insect foliovory in mangroves K. Kathiresan Centre of Advanced Study in Marine Biology, Annamalai University, Parangipettai 608 502, Tamil Nadu, India [ E-mail :
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[email protected] ] Received 1 October 2002, revised 3 April 2003 The insects cause extensive damages to mangrove leaves. The damages are visibly seen as holes, galls, necrotic spots, and incursions occurring along leaf margins. The predominant insect species are leaf-mining moth (Phyllocnistis sp.), leaf gall species (Stephaniella falcaria, Monolepta sp.), caterpillars (Dasychira sp., Capua endocypha and Odites spp.) and scale insects (Aspidiotus destructor). Avicennia species suffer more leaf damage than do Rhizophora species. This correlates negatively with tannin concentration in the leaves. [ Key words : Insect, Mangroves, Rhizophora, Avicennia, foliovory, herbivory] Insects inflict an extensive damage to mangrove January to December 2002, on the insects that existed leaves, and in extreme cases even kill the mangrove in the forests. Insects were identified following the trees1. Very little information on this aspect is keys given by Murphy6. available in India2-4. The insect-induced damage needs The common damages encountered in mangrove to be assessed in the mangroves that are ecologically leaves are holes, galls and miner attack in Avicennia very sensitive systems. In the absence of such data, it spp., necrotic spots in Ceriops decandra and is difficult to manage health of the systems, and Rhizophora spp., and incursions occurring along leaf hence, is this study. margins of Bruguiera cylindrica. In general, the Fifty leaves from each of ten species (Avicennia incidence of insects was found to be abundant during officinalis L., Avicennia marina (Forsk.) Vierh., postmonsoon months.