Diversity and distribution of subtidal benthic molluscs from the Dampier Archipelago, Western Australia; results of the 1999 dredge survey (DA2/99)

Abstract

From a dredge survey of the subtidal fauna of the Dampier Archipelago a total of 422 species of macromolluscs was identified, comprising 227 gastropods, 188 bivalves, four scaphopods and three chitons. Most species were uncommon but abundant taxa included the bivalves Melaxinaea vitrea, Corbula tunicata and C. crassa and the gastropods Herpetopoma atrata and Xenophora solarioides. Community analysis identified eight molluscan assemblages, reflecting the varied and patchy nature of the substrates that ranged from muds and silts to coarse sands, gravel, rubble and rocks. The most species-rich stations were those located inshore at water depths 10 m. These muddy stations were also notable for the diversity and abundance of suspension-feeding bivalves. Most of the mollusc species identified are distributed widely around tropical Australia and the Indo-West Pacific but a few are endemic to northwestern Australia, including the newly described lucinid bivalve Lamellolucina pilbara.