Collected samples were immediately brought back to the laboratory
and polychaetes were isolated. Terebellids were often found in sessile
organisms such as sponges, sea squirts, bivalves, and barnacles.
Worms were carefully removed from their tube nests with forceps
and checked individually for parasite infection. Each worm was
flattened between two glass plates (10 × 12 cm) and observed under
a stereomicroscope with transmitted light to detect sporocysts in the
body cavity. When sporocysts were detected, the infected polychaete
was transferred into a petri dish with clean seawater to isolate the
sporocysts. A portion of sporocysts wasfixed in 70% ethanol for molecular analyses and others were kept alive in seawater for morphological
observation. Infected polychaetes werefixed in 10% seawater formalin
and later identified based on their morphological characteristics