Drilliidae

Drilliidae
An apertural view of a shell of Cymatosyrinx parciplicata
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Caenogastropoda
clade Hypsogastropoda
clade Neogastropoda
Superfamily: Conoidea
Family: Drilliidae
Olsson, 1964
Genera and species
See text
Synonyms

Clavidae Casey, 1904 (inv., junior homonym of Clavidae McCrady, 1859 [Cnidaria], based on Clava Gmelin, 1791)

Drilliidae is a taxonomic family of small sea snails, marine gastropod mollusks in the superfamily Conoidea.[1]

This family has no subfamilies.

Contents

Description

The shell is claviform with a tall spire , or squatly conical to biconical. In many species, the siphonal canal is truncated. The aperture is U-shaped with a parietal callus pad. The sculpture of the shell shows prominent axial ribs with a polished surface. Most species have a dorsal varix (transverse elevation), except in the genera Cymatosyrinx, Elaeocyma and Splendrillia. The protoconch can be smooth or very carinate. The ovate operculum has a terminal nucleus.[2]

The radula of the species in this family have characteristically five teeth in each row (formula : 1 + 1 + 1 + 1 + 1) with a vestigial central tooth, comb-like lateral teeth and a pair of flat-pointed, slender marginal teeth.[3]

The foregut structure of the anterior alimentary system has the least derived foregut anatomy of all the families in the superfamily Conoidea.[4]

Taxonomic history

The genera in this family were originally separated from the subfamily Clavitulinae and classified by H.& A. Adams (1858) under subfamily Turritinae, because their operculum has a terminal instead of a central nucleus. In 1942 the species with a U-shaped sinus and a parietal callus pad were brought by Powell in the new subfamily Clavinae. In 1966 Morrison proposed the subfamily Drillinae ( = Clavinae) for the species with a stenoglossan radula with comb-like lateral teeth. Finally, in 1993, Taylor et al. proposed the promotion of Drillinae fom subfamily to the family level Drilliidae.[2][5]

Taxonomy

Genera in the family Drilliidae include:[6]

Genera brought into synonymy
Genera moved to other families

References

  1. ^ Bouchet, P. & Rocroi, J.-P. (2005). "Classification and Nomenclator of Gastropod Families". Malacologia 47 (1-2). 
  2. ^ a b Chen-Kwoh Chang, Small Turrids of Taiwan, Chapter 3 , History and Taxonomy of the Clavidae; June 1, 2001
  3. ^ Kantor, Yuri I; John D.Taylor (2000). "Formation of marginal radular teeth in Conoidea (Neogastropoda) and the evolution of the hypodermic envenomation mechanism". Journal of Zoology (Cambridge University Press) 252 (2): 251–262. doi:10.1111/j.1469-7998.2000.tb00620.x. 
  4. ^ Brian Morton, The Malacofauna of Hong Kong and southern China
  5. ^ Taylor, J.D., Kantor, Y.I& Sysoev, A.V.,1993 . Foregut anatomy, feeding mechanisms, reletionships and classification of the Conoidea (=Toxoglossas) (Gastropoda) Bull. Nat. Hist. Mus. Lond .(Zool) 5(2): 125-170
  6. ^ WoRMS (2010). Drilliidae. 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=23032 on1 September 2011