Species Account

Theora lubrica Gould, 1861

Tellinoidea : Semelidae

Tebble name:
Smith & Heppell name:

To size: To 15mm. Shell Structure: Thin, fragile, brittle at margins. Equivalve: Equivalve. Equilateral: Inequilateral, beaks to the anterior (although smaller specimens are more equilateral). Tumidity: Moderately swollen. Outline: Elongate ovate.

Sculpture: Smooth, fine growth stops. Margin: Smooth. Ligament: Internal on a moon-shaped chondrophore. External part is a short, brown arched band. Hinge: LV one small cardinal and single weak laterals; RV two cardinals and single laterals. Pallial Musculature: Pallial sinus deep, to between beak and anterior adductor muscle. Colour: Cream to white. Additional Characters: Interior, anterior oblique rib in both valves.

Distribution & Ecology

Native to the northwest Pacific Ocean from Russian and Japan and south to China and South Korea.

A non-native species in Australia, New Zealand and the Pacific coast of USA. Has also spread to the Mediterranean, western Spain, Netherlands and now reported in the UK (Worsfold et al, 2020). In the UK reported from Lowestoft, Suffolk and Grantham harbour, Scotland.

Depth Range

Additional Information & Related Species


Listed are literature citing Theora lubrica Gould, 1861. Reference containing the species Type Description is highlighted.

Aderraga I. & Martínez J. 2011. First record of invasive THeora lubrica (Mollusca: Bivalvia: Semelidae) in the Atlantic Ocean. Marine Biodiversity Records. 4:
Faase M., Gheerardyn H., Morys C., Van Haaren T., Ysebaert T. & Nuland R. 2019. The non-indigenous window shell THeora lubrica Gould, 1861 (Bivalvia: Cardiida: Semelidae) in the delta area of the Netherlands. Basteria. 83(1-3):
Gould A.A. 1861. Description of new shells collected by the United States North Pacific Exploring Expedition. Proceedings of the Boston Society of Natural History. 8: 14-32.
Worsfold T.M., Pennisi N. & Ashelby C.W. 2020. Theora lubrica Gould, 1861 (Bivalvia: Semelidae), new to the U.K. with notes on associated non-native species and an earlier date of introduction for Arcuatula senhousia (Bivalvia: Mytilidae) to the U.K.. Journal of Conchology. 43(6): 665-674.


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Record last modified: 23/04/2021