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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-0002619

Species ID

OC-SP-0002619

Discovered

Phylum

Platyhelminthes

Species ID

OC-SP-0002619

Provisional Species Name

Ceratopera sp_S_1889

Lowest Valid Taxon Name in WoRMS

Ceratopera

Lowest Known Rank

Genus

Status

Discovered

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

2. I/We already have plans to publish. (For marine invertebrates please know that SOSA could support you in this too - please click the button for more details).

Embargo

No

Kingdom

Animalia

Phylum

Platyhelminthes

Order

Rhabdocoela

Family

Trigonostomidae

Genus

Ceratopera

Taxonomic Remarks

The taxonomic status of the genus Messoplana has been questioned based on molecular analyses, and in databases such as WORMS, the genus has been synonymized with Ceratopera. However, I had the opportunity to check both molecular and material of the type species, M. falcata, collected in the North Sea. Such, consider that the genus Messoplana is valid, and also supported by the morphology of Messoplana sp.1 here described. The general habitus and morphology of the male atrial organs are almost identical in the three species now recognized within the genus: M. falcata, M. roscoffensis, and Messoplana sp.1. However, the bursal appendage exhibits sufficient variability to allow species differentiation. The bursal appendage of Messoplana sp.1 (18 µm long) is the smallest between species of Messoplana (M. falcata: ~26 µm in Sylt specimens, ~32 µm in the Canary Islands, and ~36 µm in Faro; and M. roscoffensis: 30–32 µm). In addition, in the previously known species the distal tubes of the bursal appendage measure more than the half of the total length of the appendage, whereas they are much smaller in Messoplana sp.1. Distinguishing, the distal rim of the tubes of the bursal appendage are thickened in Messoplana sp.1, a characteristic not found in the other species of the genus.

Received All Minimal Data for Discovery

01/04/2026

Description of Material

The stylet measures 69–86 µm in length (x¯ = 75 µm; n = 4), accompanied by a mantle 75–90 µm long (x¯ = 84 µm; n = 4). The bursal appendage is 14–21 µm long (x¯ = 18 µm; n = 4) and shows a middle ring and spine. The distal tubes show thickened rims and measure 7–10 µm long (x¯ = 9 µm; n = 4).

Ecology

Fine-grained, silty sand, 0.5 m deep, salinity 35 ‰.

Distribution

United States of America, Florida, Fort Pierce, Old Ford Park, 27.437535; -80.319533.

Scientific Name Authorship

Diez, Yander L.

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