Description: This topshell is bluntly pointed with a markedly convex profile with swollen whorls. It reaches up to 16 x 22 mm in size. There are 8-11 spiral ridges on the base of the last whorl, and the upper part of the whorls does not have ribs. The shell has a cream to green coloured background with red to red-purple stripes. It has a large, deep and circular umbilicus, which may be occluded in older animals).

Habitat: Upper shore down to reported depths of 100 m + on rocky shores, on algae and under stones. More commonly found in the littoral, although is sometimes found in the sublittoral. Can tolerate some reduced salinity.

Distribution: Found all around Britain and Ireland, although is more rare on east coast of Britain.

Similar Species: Could be confused with Steromphala cineraria, which is not as convex and has more spiral ridges (10-17) on the base of the last whorl.

Key Identification Features:

• 8-11 spiral ridges at base of last whorl.
• Cream to green background with red to red-purple stripes.
• Large, deep umbilicus.

Distribution Map from NBN: Steromphala umbilicalis at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Steromphala umbilicalis at iNaturalist World Species Observations database.

GBIF data for Steromphala umbilicalis

WoRMS: Steromphala umbilicalis at World Register of Marine Species. Accepted name: Steromphala umbilicalis (da Costa, 1778). AphiaID: 1039850.

Classification: Biota; Animalia; Mollusca; Gastropoda; Vetigastropoda; Trochida; Trochoidea; Trochidae; Cantharidinae; Steromphala