Mangroves are intertidal plants which have parts that provide equal opportunities for insects’ habitation, yet some infect species prefer certain parts than the others and consequently occur more abundantly and feed voraciously. Investigations on the abundance of insect species associated with three types of mangroves’ parts and insect functional groups in the Asarama mangrove ecosystem, Nigeria was undertaken to unravel the level of performance of the ecosystem based on the groups available. Sweep net was used to collect insects from the leaves, and forceps from roots and stems. The samples were placed in a 70% alcohol in a vial and taken to the entomology research laboratory of the Department of Animal and Environmental Biology, University of Port Harcourt for identification using taxonomic keys and grouping into functional groups. Entomofaunal abundance on mangrove parts: leaves (47), stems (36), and root (21). Abundance was highest on parts of Rhizophora mangle and lowest on Lacunlaria racemosa. Some species occur on all plant parts, while others were restricted to a particular part. Pieris rapae occurred on the leaves of 3 mangroves, but absent on stems and roots. Eighteen, fourteen, and two insect species were not found on the roots, stems and leaves, respectively, of the three mangrove habitat-types. The Asarama mangroves contained four insect functional groups: pollinators (19), predators (32), burrowers (20) and herbivores (11). The most abundant functional group was the predator group (39.02%) and the least abundant was herbivorous group (13.4%). The result also showed high abundance of Anopheles mosquitoes and low abundance of Dragonflies. Statistically a high level of significant differences in abundance of species occurred between functional groups recorded on R. mangle and A. germinas habitat-types. There was significant difference between abundance of species collected form plant parts of R. mangle and A. germinas. The implications of these results were discussed.
Keywords: Abundance, anopheles, dragonflies, functional mangroves groups, pieris rapae, plants part
