Calamiconus

Calamiconus is a subgenus of sea snails, marine gastropod mollusks in the genus Conus, family Conidae, the cone snails and their allies.^[1]

Calamiconus
Shell of Calamiconus quercinus Lightfoot, 1786, measuring 47.9 mm in height, trawled at 40 m off Maputa, in Africa
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Caenogastropoda clade Hypsogastropoda clade Neogastropoda
Superfamily:	Conoidea
Family:	Conidae
Genus:	Conus
Subgenus:	Calamiconus Tucker & Tenorio, 2009
Type species
Conus lischkeanus Weinkauff, 1875
Synonyms
Conus (Lividiconus) (Tucker & Tenorio, 2009)

In the new classification of the family Conidae by Puillandre N., Duda T.F., Meyer C., Olivera B.M. & Bouchet P. (2015), Calamiconus has become a subgenus of Conus: Conus (Lividiconus) (Tucker & Tenorio, 2009) represented as Conus Thiele, 1929^[2]

Distinguishing characteristics

The Tucker & Tenorio 2009 taxonomy distinguishes Calamiconus from Conus in the following ways:^[3]

• Genus Conus sensu stricto Linnaeus, 1758

Shell characters (living and fossil species)

The basic shell shape is conical to elongated conical, has a deep anal notch on the shoulder, a smooth periostracum and a small operculum. The shoulder of the shell is usually nodulose and the protoconch is usually multispiral. Markings often include the presence of tents except for black or white color variants, with the absence of spiral lines of minute tents and textile bars.

Radular tooth (not known for fossil species)

The radula has an elongated anterior section with serrations and a large exposed terminating cusp, a non-obvious waist, blade is either small or absent and has a short barb, and lacks a basal spur.

Geographical distribution

These species are found in the Indo-Pacific region.

Feeding habits

These species eat other gastropods including cones.^[3]

• Subgenus Calamiconus Tucker & Tenorio, 2009

Shell characters (living and fossil species)

The protoconch is multispiral, the shell is conical, the whorl tops have cords, and the shell has a moderate to deep anal notch. The periostracum is smooth, and the operculum is small.

Radular tooth (not known for fossil species)

The anterior section of the radula is much longer than posterior section, and the waist is indistinct. A basal spur is present, the barb and blade are short. Serrations are completely absent.

Geographical distribution

These species are found throughout the Indo-Pacific region.

Feeding habits

These species are vermivorous (meaning that they prey on marine worms).^[3] Calamiconus lischkeanus (Weinkauff, 1875) has been found feeding on polychaetes, Amphinomidae, and Terebellidae.^[4]

Species list

This list of species is based on the information in the World Register of Marine Species (WoRMS) list. Species within the genus Calamiconus include:^[1]

• Calamiconus escondidai (Poppe & Tagaro, 2005): synonym of Conus escondidai Poppe & Tagaro, 2005
• Calamiconus eximius (Reeve, 1849): synonym of Conus eximius Reeve, 1849
• Calamiconus garywilsoni (Lorenz & Morrison, 2004): synonym of Conus garywilsoni Lorenz & Morrison, 2004
• Calamiconus jeffreyi Petuch & Sargent, 2011: synonym of Conus quercinus [Lightfoot], 1786
• Calamiconus kermadecensis (Iredale, 1912): synonym of Conus kermadecensis Iredale, 1912
• Calamiconus lischkeanus (Weinkauff, 1875): synonym of Conus lischkeanus Weinkauff, 1875
• Calamiconus quercinus Lightfoot, 1786: synonym of Conus quercinus Lightfoot, 1786

Significance of "alternative representation"

Prior to 2009, all species within the family Conidae were placed in one genus, Conus. In 2009 however, J.K. Tucker and M.J. Tenorio proposed a classification system for the over 600 recognized species that were in the family. Their classification proposed 3 distinct families and 82 genera for the living species of cone snails. This classification was based upon shell morphology, radular differences, anatomy, physiology, cladistics, with comparisons to molecular (DNA) studies.^[3] Published accounts of genera within the Conidae that include the genus Calamiconus include J.K. Tucker & M.J. Tenorio (2009), and Bouchet et al. (2011).^[5]

Testing in order to try to understand the molecular phylogeny of the Conidae was initially begun by Christopher Meyer and Alan Kohn,^[6] and is continuing, particularly with the advent of nuclear DNA testing in addition to mDNA testing.

However, in 2011, some experts still prefer to use the traditional classification, where all species are placed in Conus within the single family Conidae: for example, according to the current November 2011 version of the World Register of Marine Species, all species within the family Conidae are in the genus Conus. The binomial names of species in the 82 cone snail genera listed in Tucker & Tenorio 2009 are recognized by the World Register of Marine Species as "alternative representations."^[7] Debate within the scientific community regarding this issue continues, and additional molecular phylogeny studies are being carried out in an attempt to clarify the issue.^{[3][8][9][10][11][12][13][14][15][16]}

All this has been superseded in 2015 by the new classification of the Conidae^[2]