Being an ancient snail lineage, ringiculids were formerly considered cephalaspideans, but latest phylogenetic works by Kano et al.(2016) tell another story. Surprisingly, both molecular and morphological features present compelling evidence for the common ancestry of ringiculid snails with the highly dissimilar Nudipleura —the most species-rich and well-known taxon of sea slugs (nudibranchs and pleurobranchoids) forming a common group named Ringipleura with category of Subterclass.

Ringicula doliaris CC-BY-4.0 by Kano et al (2016)

They are small sized but have a strong characteristic ‘bubble’ shell, hypertrophied foot and headshield as exemplified by many extant subtaxa with an infaunal mode of life.

The current taxonomy of the Ringiculimorpha is:

  • Superorder Ringiculimorpha
    • Superfamily Ringiculoidea Philippi, 1853
      • Family Ringiculidae Philippi, 1853
        • Genus Avellana d’Orbigny, 1842 †
        • Genus Microglyphis Dall, 1902
        • Genus Pseudoringicula Lin, 1980
        • Genus Ringicula Deshayes, 1838
        • Genus Ringiculoides Minichev, 1966
        • Genus Ringiculopsis Chavan, 1947
        • Genus Ringiculospongia Sacco, 1892

Ringiculimorpha species recorded in the Mediterranean or around the Iberian Peninsula:

Ringicula auriculata (Ménard de la Groye, 1811) Specimen from La Goulette, Tunisia (soft bottoms 10-15 m, 19.01.2010), actual size 3.4 mm

Ringicula auriculata

Ringicula buccinea (Brocchi,1814) [MIOCENE]

Ringicula buccinea

Ringicula conformis @ Croatia by Pero Ugarković

Ringicula conformis

Ringicula minutula

Ringicula minutula