Obese Ascidian

Phallusia obesa

Phallusia obesa is a sessile marine organism commonly found in tropical to temperate regions. This species typically resides on sandy bottoms and can often be seen attached to harbour piles. Its appearance is characterized by a robust, bulbous body that can be distinguished from similar species by its size and shape. The Obese ascidian is hermaphroditic, allowing for both cross- and self-fertilization during reproduction. Eggs develop into lecithotrophic larvae before undergoing metamorphosis into benthic adults. This ascidian is recorded in various dive sites across the Indo-West Pacific and Mediterranean regions, including Australia. Although specific depth ranges are not provided, it is generally associated with shallow marine environments. Divers may encounter this species while exploring various habitats, particularly in areas with sandy substrates or artificial structures like jetties. The diet of Phallusia obesa primarily consists of plankton and organic matter, which it filters from the water. Observing this species underwater can be intriguing, as they often blend into their surroundings, making them somewhat cryptic. However, their distinctive shape can help divers identify them amidst other marine life. The conservation status of this species has not been evaluated, and it does not have any known threats to humans.