Periostracum of T. nitida is inconspicuous or, as in above image, “obscured by an earthy incrustation” (Jeffreys, 1867).  The body of T. nitida was described by Jeffreys as “greyish, with a slight tinge of purple, and closely speckled with flake-white”. This fits some, like this specimen, but some other Adriatic T. nitida have  yellowish bodies, see fig 64.The respiratory siphon is “almost always blackish” in Ria de Vigo (Roland & Luque, 1994) but both blackish and paler siphons occur on Adriatic T. nitida.  The value of flesh and siphon colours for distinguishing T. nitida from T. reticulata elsewhere is uncertain.

Croatia, Adriatic. © P. Ugarković.