Chrysallidini

Chrysallidini
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Heterobranchia
clade Euthyneura
clade Panpulmonata
Superfamily: Pyramidelloidea
Family: Pyramidellidae
Subfamily: Odostomiinae
Tribe: Chrysallidini
Saurin, 1958[1]
Genera

See text

Chrysallidinae is a taxonomic group of very small sea snails in the family Pyramidellidae.[2]

Contents

Taxonomy

Chrysallidinae has been one of eleven recognized subfamilies of the gastropod family Pyramidellidae (according to the taxonomy of Ponder & Lindberg 1997).[3] (The other 10 subfamilies are Odostomiinae, Turbonillinae, Cingulininae, Cyclostremellinae, Sayellinae, Syrnolinae, Eulimellinae, Pyramidellinae, Odostomellinae and Tiberiinae.)

According to Schander, Van Aartsen & Corgan (1999) there are 47 genera in this subfamily, four additional genera may also be a part of this taxon.[4]

In the taxonomy of Bouchet & Rocroi (2005), this subfamily has been downgraded to the rank of tribe Chrysallidini in the subfamily Odostomiinae.[2]

Genera

Genera in the subfamily Chrysallidinae include:

Possible extra genera

Genera likely to reside in the subfamily Chrysallidinae include:

Distribution

This family is found worldwide, from the tropics to the Arctic.

Shell description

The shell of these snails has a blunt, heterostrophic protoconch, which is often wrapped up. The texture of these shells is sculptured in various forms such as ribs and spirals. Their color is mostly white, cream or yellowish. The teleoconch is dextrally coiled, but the larval shells are sinistral. This results in a sinistrally coiled protoconch. The columella has one, spiral fold. The aperture is closed by an operculum.

Life habits

The Chrysallidinae are ectoparasites, feeding mainly on other molluscs and on annelid worms.

They do not have a radula. Instead their long proboscis is used to pierce the skin of its prey and suck up its fluids and soft tissues. The eyes on the grooved tentacles are situated toward the base of the tentacles. Between the head and the foot, a lobed process called the mentum ( = thin projection) is visible.

These molluscs are hermaphrodites, laying eggs in jelly-like masses on the shell of its host.

References

  1. ^ Saurin, E. (1958). "Pyramidellidae de Pho-Hai (Sud Viet-Nam)". Annales de la Faculté des Sciences de Saigon 35: 63–86. 
  2. ^ a b Bouchet P., Rocroi J.-P., Frýda J., Hausdorf B., Ponder W., Valdés Á. & Warén A. (2005). "Classification and nomenclator of gastropod families". Malacologia: International Journal of Malacology (Hackenheim, Germany: ConchBooks) 47 (1-2): 1–397. ISBN 3925919724. ISSN 0076-2997. http://www.archive.org/details/malacologia47122005inst. 
  3. ^ Ponder, W.F. & Lindberg, D. R. (1997). "Towards a phylogeny of gastropod molluscs: an analysis using morphological characters". Zoological Journal of the Linnean Society 119: 88–265. doi:10.1111/j.1096-3642.1997.tb00137.x. 
  4. ^ Schander, C., van Aartsen, J. J., Corgan, J. C. (1999). "Families and genera of the Pyramidelloidea (Mollusca: Gastropoda)". Bollettino Malacologico 34 (9-12): 145–166. 
  5. ^ Schander, C., Lygre, F. (2010). "Six new species of pyramidellids (Mollusca, Gastropoda, Pyramidelloidea) from West Africa, introducing the new genus Kongsrudia". Zootaxa 2657: 1–17.