A Global Mission

The mission of the Ocean Census is to accelerate the discovery of ocean life to advance fundamental science, empower conservation, and fuel innovation for the future of our planet.

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Gallery

Phylum

OC-SP-0002956

Point Lonsdale;31 - Nemertea;BQDAC0020;MRG929-02;Tetrastemma sp. SMSA005;SMSA005;SP02364;AN022278;NMVF290388;PID0246308

Species ID

OC-SP-0002956

Discovered

Phylum

Nemertea

Species ID

OC-SP-0002956

Provisional Species Name

Tetrastemma sp_SMSA005

Lowest Valid Taxon Name in WoRMS

Tetrastemma

Lowest Known Rank

Genus

Status

Discovered

Does the taxonomist(s) intend to work on this material further?

3. I/We are not sure yet. This is of course no problem, we will display your species info (if not embargoed) while you work out your species description plan.

Embargo

No

Kingdom

Animalia

Phylum

Nemertea

Class

Hoplonemertea

Order

Monostilifera

Family

Tetrastemmatidae

Genus

Tetrastemma

Date Identified

16/01/2026

Taxonomic Remarks

This species is easily recognized by the mask and collar color pattern and by COI sequence data. No other known species has similar markings.

Received All Minimal Data for Discovery

08/04/2026

Description of Material

Body 21 mm long, 0.8 mm wide. Background colour white with a tinge of green in anterior third of body. With distinctive irregularly shaped brown markings over the body (dorsally and ventrally) and cephalic lobe. Brown markings on cephalic lobe form a mask over the first pair of eyes and a wide collar behind the cephalic lobe, which may be joined to the mask by a narrow middorsal strip of pigment. Small juveniles have reddish markings with more distinct banding on the body and less distinct or absent collar, and more prominent ventral markings. Cephalic lobe is diamond shaped, about twice as long as it is wide, separated from body by indistinct neck furrow. Oblique cerebral organ furrows visible dorsally and ventrally. Two pairs of ocelli, the first obscured by the cephalic pigment. Posterior tip bluntly pointed. Rhynchocoel extends to near posterior tip. Stylet basis pear shaped or cylindrical, sometimes with slight constriction in centre, widest at its distal rounded end. S/B = 0.45. Two accessory sacs with 2 stylets in each.

Ecology

Found in the seagrass Amphibolis antarctica, both intertidally and subtidally.

Distribution

Species is common in central Victoria and rare from Cape Otway to South Australia. Amphibolis antarctica is also present in Western Australia but this species is not reported from there.

Scientific Name Authorship

Maslakova, Svetlana

Point Lonsdale;31 - Nemertea;BQDAC0020;MRG929-02;Tetrastemma sp. SMSA005;SMSA005;SP02364;AN022278;NMVF290388;PID0246308

Join the census

The Ocean Census Alliance unites national and philanthropic marine institutes, museums, and universities, backed by governments, philanthropy, business and civil society partners.