Macrofauna associated with the sponge Neopetrosia exigua (Kirkpatrick, 1900) from Mauritius.

Abstract

The macrofaunal community associated with the sponge Neopetrosia exigua (Kirkpatrick, 1900) were studied across a Mauritian lagoon (West Indian Ocean).  A total of 191 individuals belonging to 18 macro-invertebrate species were found in association with the host sponge collected at depths of 1.4 – 2.7 m.  Polychaetes and amphipods mostly inhabited the sponge canals whereas crabs and brittle stars were found at bases of the sponges.  The most speciose taxon was Crustacea (61%, 11 spp.), followed by Polychaeta (33%, 6 spp.) and Echinodermata (6%, 1 sp.).  However, the most dominant species was the polychaete Haplosyllis djibouitensis (Gravier, 1900) representing 71% of total number of specimens collected.  The number of species and individuals and the diversity index values were positively, but the evenness index values were negatively correlated with the sponge volume and water depth.  The sponge N. exigua provides shelter and food for a number of invertebrates and contributes to the maintenance of biodiversity in the lagoon.