- A slow-moving worm-like sea grub, Isostichopus fuscus, related to the star fish, between 3 and 9 cm in length, which processes sea sediments to extract nutrients. The dried flesh is much prized in Asia and is used to thicken and flavour soups. The flesh is firm and gelatinous with a slight fishy flavour. The dried variety most commonly available must be soaked for several days before cooking. To prepare from fresh, wash and clean, soak overnight, blanch 5 minutes, cut open and gut, then simmer for 4 hours.