Ringiculimorpha

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
      • Ringicula auriculata (Ménard de la Groye, 1811)
      • Ringicula buccinea  Brocchi, 1814
      • Ringicula conformis Monterosato, 1877
      • Ringicula minutula Locard, 1897

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

Ringicula auriculata	Ringicula buccinea
Ringicula conformis	Ringicula minutula

Bibliography

1246567 Ringiculimorpha items 1 entomological-society-of-america author asc 1 https://opistobranquis.info/wp-content/plugins/zotpress/
Bibliography based on the works by Steve Long, 2006. Bibliography of Opisthobranchia 1554-2000 and Gary McDonald, 2009. Bibliographia Nudibranchia, with later updates from other resources.