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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-0002977

Species ID

OC-SP-0002977

Discovered

Phylum

Nemertea

Species ID

OC-SP-0002977

Provisional Species Name

Tetrastemma sp_SMTM010

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

23/07/2025

Taxonomic Remarks

Morphologically resembles a locally co-occurring species, Tetrastemma sp. SMTM002, from which it differs by the shape of stylet basis (rounded vs. truncated). Two undescribed look-alikes are known from Oman (Tetrastemma sp. SMOM006 and Tetrastemma sp. SMOM008). The two individuals depicted here differ in the presence of white anterior and posterior spots, and have COI sequence divergence of 5%, thus potentially representing two separate species. COI sequence divergence from other congeners >10%.

Received All Minimal Data for Discovery

08/04/2026

Description of Material

Body 5-7 mm long, 0.3-0.5 mm wide, translucent, with opaque, pink-tinged proboscis and opaque gut clearly showing through the body wall. With four small ocelli; anterior pair obscured by a narrow orange pigment bar. One individual has an opaque white pigment patch anterior to the orange bar and an opaque white posterior pigment spot, while the other lacks these white patches. Cerebral organ furrows are oblique and conspicuous – slanted posteriorly from ventral to dorsal, almost encircling the body, forming an anteriorly directed “V” ventrally, and a posteriorly directed “V” dorsally. Cerebral organ furrows cross over the posterior pair of ocelli and extend further posteriad toward the dorsal midline. Neck furrow inconspicuous. Stylet basis distally rounded, S/B =0.65. Two accessory stylet sacs with 2 stylets each.

Ecology

Associated with coral rubble.

Distribution

Only known from Atauro Island, Timor-Leste.

Scientific Name Authorship

Maslakova, Svetlana

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