Pyramidellidae
| Pyramidellidae | |
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| Apertural view of a shell of Pyramidella maculosa | |
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| Family: | Pyramidellidae J. E. Gray, 1840[1]
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Pyramidellidae, common name the pyram family, or pyramid shells, is a voluminous taxonomic family of mostly small and minute ectoparasitic sea snails, marine heterobranch gastropod molluscs or micromolluscs.
The pyram family is distributed worldwide with more than 6,000 species in more than 350 genera and subgenera.[2]
This family of micromollusks has been little studied and the phylogenetic relationships within the family are not well worked out. It is currently divided into 11 subfamilies (Ponder & Lindberg 1997).[3] An alternative interpretation is that the family Pyramidellidae is but one of six families within the superfamily Pyramidelloidea (Schander, van Aartsen & Corgan 1999).[4] Many species are rare or infrequently recorded.
Subfamilies
Subfamilies included within the family Pyramidellidae vary according to the taxonomy consulted. The currently leading taxonomy is the taxonomy of Bouchet & Rocroi (2005).
1997 taxonomy
Taxonomy of Pyramidellidae by Ponder & Lindberg (1997):[3]
- Chrysallidinae Saurin, 1958
- Cingulininae Saurin, 1959
- Cyclostremellinae Moore, 1966
- Eulimellinae Saurin, 1958
- Odostomellinae Saurin, 1959
- Odostomiinae Pelseneer, 1928
- Pyramidellinae J.E. Gray, 1840
- Sayellinae Wise, 1996
- Syrnolinae Saurin, 1958
- Tiberiinae Saurin, 1958
- Turbonillinae Bronn, 1849
1999 taxonomy
Taxonomy of Pyramidellidae 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
Taxonomy of Pyramidellidae by Bouchet & Rocroi (2005):[5]
- Subfamily Pyramidellinae Gray, 1840
- Tribe Pyramidellini Gray, 1840 - synonyms: Obeliscidae A. Adams, 1863 (inv.); Plotiidae Focart, 1951 (inv.)
- Tribe Sayellini Wise, 1996 - formerly subfamily Sayellinae
- Subfamily Odostomiinae Pelseneer, 1928
- Tribe Odostomiini Pelseneer, 1928 - synonyms: Ptychostomonidae Locard, 1886; Liostomiini Schander, Halanych, Dahlgren & Sundberg, 2003 (n.a.)
- Tribe Chrysallidini Saurin, 1958 - formerly subfamily Chrysallidinae, synonyms: Menesthinae Saurin, 1958; Pyrgulininae Saurin, 1959
- Tribe Cyclostremellini D. R. Moore, 1966 - formerly subfamily Cyclostremellinae
- Tribe Odostomellini Saurin, 1959 - formerly subfamily Odostomellinae
- Subfamily Syrnolinae Saurin, 1958 - formerly subfamily Syrnolinae
- Tribe Syrnolini Saurin, 1958
- Tribe Tiberiini Saurin, 1958 - formerly subfamily Tiberiinae
- Subfamily Turbonillinae Bronn, 1849
- Tribe Turbonillini Bronn, 1849 - synonym: Chemnitziinae Stoliczka, 1868
- Tribe Cingulinini Saurin, 1958 - formerly subfamily Cingulininae
- Tribe Eulimellini Saurin, 1958 - formerly subfamily Eulimellinae
In 2010 the family Pyramidellidae has been recognized as monophyletic [6]
Problematic genera
The following genera are currently difficult to place within existing subtaxa of the Pyramidellidae.
- Contraxalia Laseron, 1956[citation needed]
- Cossmannica Dall & Bartsch, 1904[citation needed]
- Eulimotibera Nomura, 1939[citation needed]
- Morrisonetta Brandt, 1968[citation needed]
- Peristichia Dall, 1889[7]
- Ulfa Dall & Bartsch, 1904[citation needed]
- Vagna Dall & Bartsch, 1904[citation needed]
Distribution
This family is found worldwide, but many species are only found in relatively small geographical ranges. The species found at the Cape Verdes are mainly endemic species. [8]
Shell description
The length of the slender, elongated (turreted or conical) shells varies between 0.5 mm and 3.5 cm, but most species in the family have shells which are smaller than 13 mm.
The texture of these shells is smooth or sculptured in various forms such as ribs and spirals. Their color is mostly white, cream or yellowish, sometimes with red or brown lines.
The shell of these snails has a blunt, heterostrophic (i.e. whorls appear to be coiled in the opposite direction to those of the teleoconch) protoconch, which is often pointed sideways or wrapped up. The teleoconch is dextrally coiled, but the larval shells are sinistral. This results in a sinistrally coiled protoconch.
The columella has usually one, but sometimes several, spiral folds. The aperture is closed by an operculum.
The operculum is ovoid and paucispiral, with the apex anterior, a thread-like arcuate ridge on the proximal side, the inner margin notched in harmony with the plaits of the pillar when prominent.
Life habits
The Pyramidellidae are ectoparasites, feeding mainly on other molluscs and on annelid worms, but some are known to feed on peanut worms and crustaceans.[9][10]
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. These tentacles have a concave surface. Between the head and the propodium (the foremost division of the foot), a lobed process called the mentum (= thin projection) is visible. This mentum is slightly indented in midline.
These gastropods are hermaphrodites, laying eggs in jelly-like masses on the shell of its host. Some species have spermatophores.[11] [12] [13]
References
- ^ Gray, J. E. (1840). Synopsis of the contents of the British Museum, 42nd edition. London. p. 370 pp.
{{cite book}}: Cite has empty unknown parameter:|month=(help) - ^ Schander C.; Halanych K.M.; Dahlgren T.; Sundberg P (2003). "Test of the monophyly of Odostomiinae and Turbonilliinae (Gastropoda, Heterobranchia, Pyramidellidae) based on 16S mtDNA sequences". Zoologica Scripta. 32 (3): 243–254. doi:10.1046/j.1463-6409.2003.00112.x.
{{cite journal}}: Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) - ^ a b 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 (2): 88–265. doi:10.1111/j.1096-3642.1997.tb00137.x.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ a b 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.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Bouchet, P. & Rocroi, J.-P. (2005). "Classification and Nomenclator of Gastropod Families". Malacologia. 47 (1–2): 1–397.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Dinapoli, Angela (10). "New insights into the phylogeny of the Pyramidellidae (Gastropoda)". Journal of Molluscan Studies. 77 (1): 1–7. doi:10.1093/mollus/eyq027. Retrieved 2011-10-25.
{{cite journal}}: Check date values in:|date=and|year=/|date=mismatch (help); Unknown parameter|coauthors=ignored (|author=suggested) (help); Unknown parameter|month=ignored (help) - ^ WoRMS (2010). Peristichia. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=415795 on 2011-03-15
- ^ J.J. van Aartsen, E. Gittenberger & J. Goud, Pyramidellidae (Mollusca, Gastropoda, Heterobranchia) collected during the Dutch CANCAP and MAURITANIA expeditions in the south-eastern part of the North Atlantic Ocean (part 2)
- ^ Sneli, J.-A. (1972). "Odostomia turrita found on Hommarus gammarus". Nautilus. 86 (1): 23–24.
- ^ Robertson, R.; Mau-Lastovicka, Terry (1979). "The ectoparasitism of Boonea and Fargoa (Gastropoda: Pyramidellidae)". Biological Bulletin. 157 (2). Marine Biological Laboratory: 320–333. doi:10.2307/1541058. JSTOR 1541058.
- ^ Høisæter, T. (1965). "Spermatophores in Chrysallida obtusa (Brown) (Opisthobranchia, Pyramidellidae)". Sarsia. 18: 63–68.
- ^ Robertson, R. (1967). "The life history of Odostomia bisuturalis and Odostomia spermatophores (Gastropoda: Pyramidellidae)". American Philosophical Society Yearbook. 1967: 368–370.
- ^ Schander C., Hori, S., Lundberg, J. (1999). "Anatomy, Phylogeny and biology of Odostomella and Herviera, with the description of a new species of Odostomella (Mollusca, Heterostropha, Pyramidellidae)". Ophelia. 51 (1): 39–76.
{{cite journal}}: CS1 maint: multiple names: authors list (link)
Further reading
- Dinapoli A., Zinssmeister C. & Klussmann-Kolb A. (2010). "New insights into the phylogeny of the Pyramidellidae (Gastropoda)". Journal of Molluscan Studies doi:10.1093/mollus/eyq027.
- Hayward P. J. &, J.S. Ryland (1996). Handbook of the Marine Fauna of North-West Europe. Oxford University Press. p. 546. ISBN 0198540558.
External links
