Cylichna cylindracea
Habitat: it lives in the infralittoral and circalittoral zones on thin sand bottoms. It is collected in remarkable depths too. It is often found into gastral cavities of Astropecten auranciacus. It feeds on protozoon. Distribution: it can be found all over the Mediterranean. Never common.
Notes: this species is easily recognizable due to its outline particularly stretched, with a H/L ratio usually more than 2.5. Shell distinctly cylindrical in form. In upper part external lip overhanges spiral originating apical crown on which there are present weak striae only. In apical zone it is present an umbilicus not much deep. Aperture runs parallel and near columellar margin, in the lower part it is truncated and columella presents a weak plica. Sculpture is made by a spiral streaking undulated that, as far as fresh specimens are concerned, is brown in colour, more evident at the two ends. Living specimens have a periostracum uniform light brown in colour. Definitely cylindrical in outline and this makes it easily recognizable even during its juvenile stage. Cylichna elongata Locard, 1886 is considered a synonym of this species. Average measures of adult specimens reach 6-7 mm in height but specimens more than one centimetre are not rare.