Biodiversity and host specificity of sponge-associated barnacles (Cirripedia: Thoracica) in Thailand

Abstract

We examined the diversity and host use of sponge-associated barnacles of Thailand (Andaman Sea and the Gulf of Thailand) using a combined morphological and molecular approach. Eight barnacle species (including two new species) were collected from 12 host sponges. Host-specific barnacle species includes Acasta lappa sp. nov., which exclusively inhabits the sponge Mycale sp. Acasta milkae sp. nov. was only collected from the sponge Callyspongia cf. diffusa (Ridley, 1884). Multatria filigranus (Broch, 1916) were found in the encrusting soft sponges Monanchora unguiculata (Dendy, 1922) and Clathria sp. Pyrgospongia stellula (Rosell, 1975) inhabits the sponges Spheciospongia vagabunda (Ridley, 1884). Generalist barnacle species includes Euacsta ctenodentia (Rosell, 1972), E. porata (Nilsson-Cantell, 1921), E. zuiho (Hiro, 1936), and Acasta cyathus Darwin, 1854, which inhabit a wide range of sponges with various textures.