Shell is brittle, somewhat flattened, slightly inequivalve, right valve a little more convex than the left. Inequilateral, beaks just behind the midline, directed inwards and backwards, almost touching. Approximately oval in outline with the posterior region somewhat attenuated and strongly curved to the right. Ligament is a green-brown arched band extending backwards from the beaks one-third the way to the posterior margin, set on a broad nymphal plate. Sculpture of concentric lines with, in the right valve only, diagonal lines running from the upper right to the lower left superimposed upon them. Growth stages are clear. Right valve with two cardinal teeth of which the posterior is bifid, one short prominent anterior lateral and one small ridge-like posterior lateral just behind and below the nymphal plate. Left valve with two cardinals of which the anterior is bifid and one short and weak posterior lateral but no anterior lateral. The ridge which runs in front of the beaks in the left valve is not here considered a tooth. Cruciform muscle scars are generally indistinct. Pallial sinus is a deep broad quadrate incision, its lower border confluent with the pallial line and its anterior line curved and close to the anterior adductor scar. Margin is smooth (T. fabula-drawing).
Up to 19 mm in length.
White in colour with tinges of yellow or orange. Periostracum transparent, glossy. Inside of shell white, sometimes with pale tinges of orange or yellow.
A deep burrower in sand or mud. This habit has had effect in developing a powerful foot and in lengthening and separating the siphons. The siphons are nearly equal in length. The lips are large, the gills are unequal in size and the mantle is fringed with tentacles. Colour clear white (Tellina sp.-animal).
Clean silty sand, sand, or muddy sand, from the middle or lower regions of the intertidal zone to a depth of about 55 m.
It is distributed from about 70°N, off the Norwegian coast and the Baltic, south to the Iberian Peninsula, into the Mediterranean and Black Sea, and along the Atlantic coast of Morocco (Distr. T. fabula).