Hiatella arctica Linnaeus, 1767
|Phylum:||Mollusca Linnaeus, 1758|
|Class:||Bivalvia Linnaeus, 1758|
|Synonyms:||Mya arctica Linnaeus, 1767; Saxicava pholadis (Linnaeus, 1771); Tellina rhomboides Gmelin, 1791|
To size: To 40mm.
Shell Structure: Brittle rather thin. Equivalve: Equivalve. Equilateral: Inequilateral beaks close to the anterior. Outline: Trapezoidal - modioliform; anterior greatly reduced, umbos prominent; anterior dorsal margin sloping steeply, straight or concave to narrowly rounded anterior ventral; ventral margin long, straight or sinuous; Posterior dorsal margin long diverging from ventral margin to give a broad curved or subtruncate posterior. Posterior area set of by an angular umbonal posterior ventral ridge.
Sculpture: Of irregular co-marginal ridges and lines; posterior area with two radial ribs usually ornamented with short hollow spines. Margin: Inner margin smooth. Ligament: External, sunken, about 1/4 length of posterior dorsal margin. Hinge: Hinge teeth usually worn but RV with a single peg-like cardinal; LV with two similar cardinals. Pallial Musculature: Adductor scars unequal, posterior slightly the larger; pallial line fragmented, pallial sinus deep. Periostracum: Persistent, straw coloured. Colour: Shell white.
A nesting species attached by a weak byssus in crevices on hard substrates and among coarse ground and Modiolus beds and in kelp holdfasts. From the low intertidal to the shelf edge and upper slope. Widespread.
Depth: 0 - 500 m