Pyramidelloidea

Pyramidelloidea is a superfamily of mostly very small sea snails, marine gastropod mollusks and micromollusks within the clade Panpulmonata.^[2]

Pyramidelloidea
live Turbonilla acutissima
Two views of a shells of Pyramidella acus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subcohort:	Panpulmonata
Superfamily:	Pyramidelloidea J. E. Gray, 1840[1]

This is a voluminous taxon: above the species level close to 400 named taxa are referred to this gastropod superfamily.

Pyramidelloidea has both fossil and recent members. They live as ectoparasites on bivalve molluscs and polychaete worms, and have a sharp, piercing stylet instead of a radula.^[3]

Distribution

This taxon is found worldwide.

Taxonomy

1999 taxonomy

Taxonomy by Schander, Van Aartsen & Corgan (1999):^[4]

• Superfamily Pyramidelloidea Gray, 1840
  • Family Amathinidae Ponder, 1987
  • Family Ebalidae Warén, 1994 - synonym: Anisocyclidae van Aartsen, 1995
  • Family Odostomiidae Pelseneer, 1928
    • Subfamily Odostomiinae Pelseneer, 1928
    • Subfamily Chrysallidinae Saurin, 1958
    • Subfamily Odostomellinae Saurin, 1958
    • Subfamily Cyclostremellinae Moore, 1966
  • Family Pyramidellidae J. E. Gray, 1840
    • Subfamily Pyramidellinae J.E. Gray, 1840
    • Subfamily Sayellinae Wise, 1996
  • Family Syrnolidae Saurin, 1958
    • Subfamily Syrnolinae Saurin, 1958
    • Subfamily Tiberiinae Saurin, 1958
  • Family Turbonillidae Bronn, 1849
    • Subfamily Turbonillinae Bronn, 1849
    • Subfamily Eulimellinae Saurin, 1958
    • Subfamily Cingulininae Saurin, 1959

2005 taxonomy

Pyramidelloidea has been classified within the informal group Lower Heterobranchia in the taxonomy of Bouchet & Rocroi (2005).^[5]

Taxonomy of Bouchet & Rocroi, 2005:

• Superfamily Pyramidelloidea
  • Family Pyramidellidae
  • Family Amathinidae
  • † Family Heteroneritidae
  • Family Murchisonellidae

2010 taxonomy

Jörger et al. (2010)^[2] have redefined major groups within the Heterobranchia and they moved Pyramidelloidea to Panpulmonata.^[2]

Pyramidelloidean genera of uncertain familial position

• Bidentata de Castellanos, 1982
• Calyptopolyptychia Gougerot, 1968
• Laeviselica Gougerot & Le Renard, 1977
• Lysacme Dall & Bartsch, 1904
• Microthyca A. Adams, 1863
• Oopyramis Thiele, 1930
• Sulcorinella Dall & Bartsch, 1904