Visit Our Diving Center
View our Accommodation
  • Immersioni
    • Corsi Diving
    • Apnea Diving
    • Immersioni Accompagnate
    • Listino Prezzi Sub
  • Alloggio
  • Offerte Speciali
  • Servizi di Vacanza
  • Siti di Immersione
  • Gozo
  • Chi siamo
  • Contattaci
Negozio on-line Dive Checkin
  • IT
    • EN
    • FR
    • DE
    • PL
  • Immersioni
    • Corsi Diving
    • Apnea Diving
    • Immersioni Accompagnate
    • Listino Prezzi Sub
  • Alloggio
  • Offerte Speciali
  • Servizi di Vacanza
  • Siti di Immersione
  • Gozo
  • Chi siamo
  • Contattaci
30. 08. 202030. 08. 2020

Green Spoonworm (Bonellia viridis)

Home » Blog » Green Spoonworm (Bonellia viridis)
Bonellia viridis

Bonellia viridis, the Green Spoonworm (a.k.a. Green Bonellia), is a wide-ranging marine worm species found all along the north-eastern coast of the Atlantic Ocean and the entire Mediterranean Sea, thus also around the Maltese Islands.  It is quite noted for displaying exceptional sexual dimorphism (the male being extremely smaller than the female) and for the biocidal properties of a pigment in its skin.

The genus name Bonellia was first described by the Turin doctor Luigi Rolando in 1821, who named it in honour of his friend, the Italian ornithologist, entomologist and collector Franco Andrea Bonelli (10 November 1784 – 18 November 1830).  The specific name viridis derives from Latin and means green, evidently denoting the green colour of the body.

The genus Bonellia belongs to the family Bonelliidae, order Bonelliida, class Echiura, phylum Annelida and kingdom Animalia.

The pale to dark-green female, with a 15 cm-long, round or sausage-shaped body, lives on the sea bottom at a depth of 10 to 100 metres.  The Green Spoonworm conceals itself by burrowing in gravel or hiding in rock crevasses.  Otherwise, it inhabits burrows abandoned by other animals.

Bonellia viridis has two anchoring hooks underneath its body and an extensible feeding proboscis up to 10 times its body-length, thus 1.5 metres long.  It is mainly a detritivore, feeding also on small animals.  The male is rarely observed: it has a flat, unpigmented body which grows to only 1 to 3 mm, taken up mostly by reproductive organs and devoid of other structures.  The male lives on or inside the body of a female.

The adult Green Spoonworm 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.  It is currently being investigated as a possible model for novel antibiotics.

Most larvae, however, once they come in contact with the bonellin in the skin of an adult female, its body or its roving, bonellin-rich proboscis, they 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 thus determined by external, environmental factors (the presence or absence of bonellin), not by internal, genetic factors (chromosomes), as is the case with most other sexually-differentiated organisms. This environmental sex determination helps Bonellia viridis populations respond to the availability of burrows.

The photo of this Green Spoonworm was taken at a depth of 58m at Reqqa Point on Gozo’s north coast.

Photo taken by Brian Azzopardi

Notizie simili

Bath Sponge
05. 02. 2021

Bath Sponge (Spongia officinalis)

Spongia officinalis, better known as a variety of Bath Sponge, is a commercially used sea sponge.  Individuals grow in large...

Di più
Green Boring Sponge
09. 01. 202109. 01. 2021

Green Boring Sponge (Cliona viridis)

Cliona viridis, the Green Boring Sponge, is a species of demosponge found along the eastern coast of the Atlantic Ocean,...

Di più
Merry Christmas
11. 12. 2020

Merry Christmas & A Happy New Year 2021

Merry Christmas & A Happy New Year 2021 Wishing you all the best ! Happy Holidays from the Atlantis Gozo...

Di più

Reviews

Tolles Center für Sport- Tec und Rebreather Taucher. Bestens zu empfehlen 😃, immer wieder gerne hier 👍.
Manfred Kleemann
Manfred Kleemann
2022-05-23T05:51:17+0000
Our club goes out to Malta/Gozo every year and Atlantis was by far the best centre we have dealt with. The communication building up to the trip was great. So helpful. Our club has a mixed range of diver levels and Atlantis made sure that all our levels was covered. On arrival the welcome was very warming. They couldn’t have been more helpful. Once the admin and kit issue was done we was on our way. The end I’ve every day the team was on hand to assist us making sure we was all prepared for the following day. Nitrox, stages, fills and so on. The end of our trip the staff even came to the apartment to say farewell and seen us off. One of our club members left their regs by mistake but the team contacted us and meet us at the ferry port to return them. Thank you so much!!! We will be returning next year.
Alex Lucas
Alex Lucas
2022-04-21T07:36:58+0000
Highly recommended dive centre! We got all needed services in very friendly atmosphere. Thank you!!
Gedimas Usack
Gedimas Usack
2021-11-27T20:24:01+0000
I did a package deal of 10 dives with Atlantis and was extremely impressed from the get go. The center was very well equipped and maintained and the staff were awesome, totally committed to making sure everyone was welcomed and having fun whilst keeping a high level of professionalism. The guides (Denis, Georgia, Apollo, George) were very knowledgeable and friendly. I highly recommend Atlantis to anyone looking for a solid and trustworthy center with fair prices. P.s. Go in November, its way less busy and the vis is still good!
Jakob Wayne Víkingur Robertson
Jakob Wayne Víkingur Robertson
2021-11-18T01:22:10+0000
awesome place awesome people!
Richard Binks
Richard Binks
2021-10-20T05:07:13+0000
‹
›

Newsletter

Iscriviti alla nostra newsletter, ricevi le ultime notizie e le offerte speciali da parte del team Atlantis! Facendo questo accetti i nostri Privacy Policy

Mailchimp
Sending
  • Chi siamo
    • Lavora con noi
    • Partner
  • Immersioni
    • Corsi Diving
    • Corsi PADI
    • CMAS & VDST Kurse
    • BSAC Courses
    • Corsi di Specialità
    • Immersioni Accompagnate
    • Immersioni non-accompagnate
    • Immersioni TEK
    • Noleggio attrezzatura
    • Listino Prezzi Sub
  • Siti di Immersione
  • Servizi di Vacanza
    • Alloggio
    • Trasferimento da/per aeroporto
    • Autonoleggio
    • Escursioni
  • Offerte Speciali
  • Gozo
  • Galleria di foto
    • Ringraziamenti per le foto
  • Contattaci

Copyright © 2023 Atlantis Diving Center. All rights reserved.
Informativa sulla privacy | CONDIZIONI GENERALI | Refund Policy

Website designed & developed by