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''Laevistrombus canarium'' (commonly known as the dog conch or by its better-known synonym, ''Strombus canarium'') is a species of edible sea snail, a marine gastropod mollusc in the family Strombidae (true conches). Known from illustrations in books dating from the late 17th century, ''L. canarium'' is an Indo-Pacific species occurring from India and Sri Lanka to Melanesia, Australia and southern Japan. The shell of adult individuals is coloured from light yellowish-brown to golden to grey. It has a characteristic inflated body whorl, a flared, thick outer lip and a shallow stromboid notch. The shell is valued as an ornament, and because it is heavy and compact it is also often used as a sinker for fishing nets. The external anatomy of the soft parts of this species is similar to that of other strombid snails. The animal has an elongate snout, thin eyestalks with well-developed eyes and sensory tentacles, and a narrow, strong foot with a sickle-shaped operculum. A molecular analysis conducted in 2006 based on DNA sequences of histone and mitochondrial genes demonstrated that ''Laevistrombus canarium'', ''Doxander vittatus'' and ''Labiostrombus epidromis'' are closely related species. The dog conch exhibits behaviours common among Strombidae, including burrowing and a characteristic leaping form of locomotion. The former behaviour, however, involves movement sequences unique to this species. ''Laevistrombus canarium'' lives on muddy and sandy bottoms, grazing on algae and detritus. It is gonochoristic and sexually dimorphic, depending on internal fertilization for spawning. Larvae of this species spend several days as plankton, undergoing a series of transformations until they reach complete metamorphosis. The maximum life span is 2 to 2.5 years. Predators of this snail include carnivorous gastropods such as cone snails and volutes. It is also a prey species for vertebrates including macaques, and also humans, who consume the soft parts in a wide variety of dishes. The dog conch is an economically important species in the Indo-West Pacific, and several studies indicate that it may be suffering population declines due to overfishing and overexploitation. Malacologists and ecologists have recommended a reduction in its exploitation rate; initiatives in Thailand are attempting to ensure the possibility of reproduction in young-adult individuals and manage the natural populations in general. ''L. canarium'' demonstrates the imposex phenomenon, but is resistant to sterility caused by it; therefore, it has been suggested that this species might be useful as a bioindicator for organotin pollution monitoring near Malaysian ports. == Taxonomy == The first published depictions of the shell of this species appeared in 1681 in the earliest book solely about sea shells, ''Recreatio mentis et oculi in observatione animalium testaceorum'' (''Refreshment of the mind and the eye in the observation of shell-bearing animals'') by Italian scholar Filippo Buonanni. The species was shown in the 1742 ''Index Testarum Conchyliorum, quae adservantur in Museo Nicolai Gualtieri'' (''List of the shells of shellfish which are preserved in the museum of Niccolò Gualtieri'') by Italian physician and malacologist Niccolò Gualtieri. In both books, the morphology of an adult shell was shown from different perspectives.〔 In 1758, the dog conch was formally described and named ''Strombus canarium'' by Swedish naturalist and taxonomist Carl Linnaeus, who originated the system of binomial nomenclature. The specific name of this taxon, ''canarium'', is derived from the Latin ''canis'' (dog). The original description given by Linnaeus in his book, ''Systema Naturae'', is in Latin: "''S. testae labro rotundato brevi retuso, spiraque laevi''." This can be translated as "''Strombus'' with a shell having a retuse, short, rounded lip, and a smooth spire". Linnaeus did not mention a specific locality in his original description, giving only Eastern Asia as the area in which the species is found. The taxon ''Laevistrombus'' was introduced in the literature as a subgenus of ''Strombus'' by Tetsuaki Kira (1955) in the third printing of the 1st edition of ''Coloured Illustrations of the Shells of Japan''. It comprised two species, ''Strombus (Laevistrombus) canarium'' and ''Strombus (L.) isabella'' Lamarck, 1822. No type specimen was designated, and Kira gave no formal description or statement of differentiation, as required by the ICZN code to validate the name. In a later version of the book, ''Laevistrombus'' was elevated to genus level, but a description was still lacking. Rüdiger Bieler and Richard Petit (1996) considered it a ''nomen nudum'', and the authorship was transferred to Robert Tucker Abbott (1960), who had provided a proper description and illustrations of ''Laevistrombus'' and specified a type species, ''Strombus canarium'' L., in the first volume of his monograph ''Indo-Pacific Mollusca''. The currently accepted combination, ''Laevistrombus canarium'', was proposed by Jack John Sepkoski Jr. (2002), who elevated ''Laevistrombus'' to genus level based on palaeontological data. The synonyms are other binomial names that were given over time to this taxon by authors who were unaware that the specimens they were describing belonged to a species already described by Linnaeus; in some cases, local variations in colour and form may have misled these authors into thinking they had a different species. ''Strombus vanicorensis'' is a subsequent, changed spelling of ''Strombus vanikorensis'' by one of the original authors.〔〔 There is some disagreement in the literature as to whether or not this taxon and the similar-looking ''Laevistrombus turturella'' are actually separate species. Leo Man In 'T Veld and Koenraad de Turck (1998) considered that ''L. canarium'' and ''L. turturella'' are distinct (yet sympatric) species, based mainly on the shell morphology and a radula comparison.〔 However, when Zaidi Che Cob reviewed a number of ''Strombus'' species in 2009, examining both shell characters and anatomical data including details of the genitalia, operculum and radula, he concluded that ''L. turturella'' was simply a morphotype, and therefore a synonym of ''L. canarium''.〔 ''Laevistrombus canarium'' comprises at least two known subspecies; one is the nominate subspecies ''Laevistrombus canarium canarium'', and the other is ''Laevistrombus canarium guidoi''. ''L. canarium guidoi'' distinguishes itself from the other subspecies by its solid white colour, the outline of the posterior canal and a more prominent posteriorly protruding outer lip. The presence of a freely protruding lip at the posterior portion of the columella is also a distinctive character. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Laevistrombus canarium」の詳細全文を読む スポンサード リンク
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