In today's world, Conoidea has become a topic of great importance and interest to a wide variety of people. Whether it's a cultural phenomenon, a historical figure, or a contemporary concept, Conoidea has captured the attention of experts, enthusiasts, and scholars alike. Its impact extends to different aspects of modern life, from politics and economics to popular culture and society in general. In this article, we will explore in depth the meaning and relevance of Conoidea, analyzing its origins, its evolution over time and its influence on the world today.
Conoidea is a superfamily of predatorysea snails, marinegastropodmollusks within the suborder Hypsogastropoda. This superfamily is a very large group of marine mollusks, estimated at 340 recent valid genera and subgenera, and considered by one authority to contain 4,000 named living species.[3]
This superfamily includes the turrids, the terebras (also known as auger snails or auger shells) and the cones or cone snails.[3] The phylogenetic relationships within this superfamily are poorly established. Several families (especially the Turridae), subfamilies and genera are thought to be polyphyletic.[3]
In contrast to Puillandre's estimate, Bandyopadhyay et al. (2008)[4] estimated that the superfamily Conoidea contains about 10,000 species. Tucker (2004) even speaks of 11,350 species in the group of taxa commonly referred to as turrids.[5] 3000 recent taxa are potentially valid species. Little more than half of the known taxa are fossil species. Many species are little known and need more investigation to find their exact systematic place.[5]
Most species in this superfamily are small to medium, with shell lengths between 3 mm and 50 mm. They occur in diverse marine habitats from tropical waters to the poles, in shallow or deep waters, and on hard to soft substrates.
The superfamily is known for its toxoglossan radula, which is used to inject powerful neurotoxins into its prey. This makes these species powerful carnivorous predators on annelid, other mollusc and even fish.
Within the superfamily there are four somewhat different varieties of radula.[6] The radula types[7] are as follows:
Type 1 Drilliidae type: five teeth in each row with comb-like lateral teeth and flat-pointed marginal teeth
Type 2 Turridae s.l. type: two or three teeth in a row with the marginal teeth being of the duplex or wishbone form
Type 3 Pseudomelatomidae type: two or three teeth in a row with curved and solid marginal teeth
Type 4 hypodermic type: two hollow, enrolled, marginal teeth in each row with an absent or reduced radular membrane
In 2009, a proposed new classification of this superfamily was published by John K. Tucker and Manuel J. Tenorio. In 2011, a new classification of this superfamily was published by Bouchet et al. Both classifications were based upon cladistical analyses and included modern taxonomic molecular phylogeny studies.
Families
1993 taxonomy
Families and subfamilies included within the superfamily Conoidea according to Taylor, et al. 1993[8]
Turridae H. Adams & A. Adams, 1853 (1838) – turrids
This same classification was accepted by Bouchet & Rocroi in 2005.[9]
2009 taxonomy
In 2009 John K. Tucker and Manuel J. Tenorio proposed a classification system for the cone shells and their allies (which resorb their inner walls during growth) based upon a cladistical analysis of anatomical characters including the radular tooth, the morphology (i.e. shell characters), as well as an analysis of prior molecular phylogeny studies, all of which were used to construct phylogenetic trees.[10] In their phylogeny, Tucker and Tenorio noted the close relationship of the cone species within the various clades, corresponding to their proposed families and genera; this also corresponded to the results of prior molecular studies by Puillandre et al. and others.[11][12][13][14][15][16][17] This 2009 proposed classification system also outlined the taxonomy for the other clades of Conoidean gastropods (that do not resorb their inner walls), also based upon morphological, anatomical, and molecular studies, and removes the turrid snails (which are a distinct large and diverse group) from the cone snails and creates a number of new families.[10] For Tucker and Tenorio's classification system for the cone shells and their allies (and the other clades of Conoidean gastropods) see Tucker & Tenorio cone snail taxonomy 2009.
2011 taxonomy
The original classification, Taylor et al. 1993 (and Bouchet & Rocroi in 2005) was thoroughly changed by the publication in 2011 of the article.[18] The authors presented a new classification of the Conoidea on the genus level, based on anatomical characters but also on the molecular phylogeny as presented by Puillandre N., et al., 2008.[19] They recognize fifteen families: Conidae, Terebridae, and the polyphyletic family Turridae resolved into 13 monophyletic families (containing 358 currently recognized genera and subgenera). The authors follow tentatively the classification for the family Conidae as presented by Tucker & Tenorio, 2009[10] who divided the monogeneric family Conidae into 82 genera. However, there is no final opinion on this issue yet, as a new molecular phylogeny of the Conidae is in preparation. There are a number of genera within the Conoidea that could not be assigned to any family.
In 2012, a new lineage in the Conoidea was revealed, leading to the creation of a new family Bouchetispiridae Kantor, Strong & Puillandre, 2012 that includes one genus Bouchetispira Kantor, Strong & Puillandre, 2012 and one species Bouchetispira vitrea Kantor, Strong & Puillandre, 2012, which was found on an isolated sea mount off New Caledonia. This is probably the sole survivor of a larger clade.[20]
^Fleming J. (June 1822). The philosophy of zoology, a general view of the structure, functions and classification of animals2. Constable & Co., Edinburgh, 618 pp., Conidae is on the page 490.
^Taylor, J. D.; Kantor, Y. I.; Sysoev, A. V. (1993). "Foregut anatomy, feeding mechanisms, relationships and classification of Conoidea (Toxoglossa) (Gastropoda)". Bull. Br. Mus. (Nat. Hist.) Zool. 59: 125–169.
^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. ISBN3-925919-72-4. ISSN0076-2997
^ abcTucker J.K. & Tenorio M.J. (2009) Systematic classification of Recent and fossil conoidean gastropods. Hackenheim: Conchbooks. 296 pp., at p. 133
^P.K. Bandyopadhyay, B.J. Stevenson, J.P. Ownby, M.T. Cady, M. Watkins, & B. Olivera (2008), The mitochondrial genome of Conus textile, coxI-conII intergenic sequences and conoidean evolution. Molecular Phylogenetics and Evolution 46: 215-223.
^S.T. Williams & T.F. Duda, Jr. (2008), Did tectonic activity stimulate Oligo-Miocene speciation in the Indo-West Pacific? Evolution 62:1618-1634.
^R.L. Cunha, R. Castilho, L. Ruber, & R. Zardoya (2005), Patterns of cladogenesis in the venomous marine gastropod genus Conus from the Cape Verde Islands Systematic Biology 54(4):634-650.
^T.F. Duda, Jr. & A.J. Kohn (2005), Species-level phylogeography and evolutionary history of the hyperdiverse marine gastropod genus Conus, Molecular Phylogenetics and Evolution 34:257-272.
^T.F. Duda, Jr. & E. Rolan (2005), Explosive radiation of Cape Verde Conus, a marine species flock, Molecular Ecology 14:267-272.
^B. Vallejo, Jr. (2005), Inferring the mode of speciation in the Indo-West Pacific Conus (Gastropoda: Conidae), Journal of Biogeography 32:1429-1439.
^N. Puillandre, S. Samadi, M. Boesselier, A. Sysoev, Y. Kantor, C. Cruaud, A. Couloux, & P. Bouchett (2008), Starting to unravel the toxoglossan knot: molecular phylogeny of the "turrid" (Neogastropoda: Conoidea), Molecular Phylogenetics and Evolution 47:1122-1134.
Kantor, Y. I.; Taylor, J. D. (2000). "Formation of marginal radular teeth in Conoidea (Neogastropoda) and the evolution of the hypodermic envenomation mechanism". Journal of Zoology. 252 (2): 251. doi:10.1111/j.1469-7998.2000.tb00620.x.