Medusa Spaghetti Worm

Loimia medusa, commonly known as a Spaghetti Worm, have thin, long white tentacles to 45 cm. The worm body buried in the substrate.

Distribution

Indo-Pacific and Western Central Atlantic. Tropical and subtropical.

Habitat and Biology

Loimia medusa takes residence amongst tide pools, deep estuarine channels, shallow reefs, and rubble in both bays and seas at depths up to 75 m. As this species cannot actively hunt it prefers to live in areas which are well protected and where plentiful and frequently replenished organic detritus occurs. For sufficient build-up of organic detritus to occur, an area needs to be of relatively high in biomass and productivity, such as coral reefs. Loimia medusa settles in sheltered areas, with either rocks or coral for example, from which they construct a tube from sand and gravel which it cements with a mucus-like secretion. If not, they simply protect their body in vertical holes on the soft seafloor or in reef crevices. Members of the class Polychaeta are mostly gonochoric (sexual). Mating: Females produce a pheromone attracting and signalling the males to shed sperm which in turn stimulates females to shed eggs, this behavior is known as swarming. Gametes are spawned through the metanephridia or body wall rupturing (termed as "epitoky", wherein a pelagic, reproductive individual, "epitoke", is formed from a benthic, nonreproductive individual, "atoke"). After fertilization, most eggs become planktonic; although some are retained in the worm tubes or burrowed in jelly masses attached to the tubes (egg brooders). Life Cycle: Eggs develop into trocophore larva, which later metamorph into juvenile stage (body lengthened), and later develop into adults. Spawns during summer.