Bonellia viridis (Green spoonworm)


The female Green spoonworm has a round or sausage-shaped body and the color is pale- to dark-green.
It has two anchoring hooks underneath its body and an extensible feeding proboscis (tubular mouthparts) up to 10 times its body-length.


Has not yet been assessed for the IUCN Red List.


Found in the north-eastern Atlantic Ocean, Indian and Pacific Oceans, and the Mediterranean and Red seas.
Lives on the sea-floor at a depth of 10 to 100 metres, concealed by burrowing in gravel or hiding in rock crevasses or burrows abandoned by other animals.


Sexual dimorphism.
The planktonic, free-swimming Bonellia larvae are initially sexually undifferentiated. Larvae which land on unoccupied sea-floor mature, over the period of years, into adult females. Most larvae, however, come in contact with the bonellin in the skin of an adult female and are masculinised by this exposure.
The chemical causes these larvae to develop into the tiny males, which cling to the female’s body or are sucked inside it by the feeding tube, to spend the remainder of their lives inside her genital sac, producing sperm to fertilize her eggs, reliant on her for all other needs.
The sex of a Green Spoonworm is determined by external, environmental factors (the presence or absence of bonellin)


15 cm (female)

Prey / Predation

Detritivore and small animals.

The adult female produces a vivid green pigment in its skin, known as bonellin. This chemical, concentrated mostly in the proboscis, is highly toxic to other organisms, capable of paralyzing small animals. In the presence of light, bonellin is a very effective biocide, killing bacteria, larva of other organisms, and red blood cells in laboratory tests.

Special features

The male is rarely observed: it has a flat, unpigmented body which grows to only 1–3 mm, taken up mostly by reproductive organs and devoid of other structures; it lives on or inside the body of a female.