Mactra glauca Born, 1778Mactroidea : Mactridae
To size: To 115mm. Shell Structure: Thin, solid. Equivalve: Equivalve. Equilateral: Inequilateral, beaks to the front. Tumidity: Fairly tumid. Outline: Broadly triangular. Anterior dorsal margin lower and shorter than posterior. Posterior dorsal margin almost straight. Both anterior and posterior margins broadly rounded, although the posterior more so.
Sculpture: Fine concentric lines. Posterior dorsal area has rough, raised concentric ridges. Growth stages clear. Margin: Smooth. Ligament: External small dark brown behind the beaks. Internal on a spoon-shaped chondrophore. A tiny, thin cream coloured septum separates the internal and external. Hinge: LV three cardinals and single anterior and posterior laterals. Two of the cardinals are inverted v-shaped and the third, which is very thin and can be broken, lies directly behind the rear cardinal and can be overlooked. RV two cardinals, the anterior at around 40° to the dorsal margin, and double anterior and posterior laterals. The lower laterals are longer than the upper laterals. Pallial Musculature: Very shallow pallial sinus - reaching midway between midpoint and anterior of posterior adductor. Periostracum: Pale brown, darker to the anterior and posterior. Colour: White with pale brown radiating rays.
Distribution & Ecology
A southern species ranging to the Channel Islands and the extreme south west of England. All records are early 20th century. Records in the NBN Gateway from the North Sea are doubtful.
Continental Shelf (to 200m)
Juveniles & Similar Species
Key Features & Similar Species
Listed are literature citing Mactra glauca Born, 1778. Reference containing the species Type Description is highlighted.
Born I von 1778. Index rerum naturalium Museum Caesarei Vindonbonensis pars 1, testacea Kraus, Vienna. 458pp.
- Conchological Society
of Great Britain & Ireland
Provides resources for understanding, identifying, recording, and conserving molluscs
Check List of European Marine Mollusca
The Marine Life Information Network for Britain and Ireland (MarLIN) provides information for marine environmental management, protection and education. It is a centre of excellence in spatially based and time-series marine biological information and supports good stewardship in the marine environment.
- NBN Gateway
National Biodiversity Network's Gateway. Use it to explore UK biodiversity data, as contributed by participating data providers.
- Malacological Society
- Unitas Malacologica
- Census of Marine Life
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