Strombidae | |
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Three shells of three species in the family Strombidae: lower left Laevistrombus turturella , upper center Lambis lambis , lower right Euprotomus aurisdianae | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Gastropoda |
Subclass: | Caenogastropoda |
Order: | Littorinimorpha |
Superfamily: | Stromboidea |
Family: | Strombidae Rafinesque, 1815 |
Genera | |
See text |
Strombidae, commonly known as the true conchs, is a taxonomic family of medium-sized to very large sea snails in the superfamily Stromboidea, and the Epifamily Neostromboidae. The term true conchs, being a common name, does not have an exact meaning. It may generally refer to any of the Strombidae [1] but sometimes is used more specifically to include only Strombus and Lambis. [2] The family currently includes 26 extant, and 10 extinct genera.
Strombid gastropods live mainly in tropical and subtropical waters. These animals are widespread in the Indo-West Pacific, where most species and genera occur. [3] Nearly 40 of the living species that used to belong to the genus Strombus can be found in the Indo-Pacific region. [4] They also occur in the eastern Pacific and Western Atlantic, and a single species can be found on the African Atlantic coast. [3] Six species of strombids are found in the wider Caribbean region, including the queen conch Aliger gigas , the goliath conch Titanostrombus goliath , the hawk-wing conch Lobatus raninus , the rooster tail conch Aliger gallus , the milk conch Macrostrombus costatus , the West Indian fighting conch Strombus pugilis , and the Florida fighting conch Strombus alatus . Until recently, all of these species were placed in the genus Strombus, but now many species are being moved into new genera. [5]
Strombids have long eye stalks. The shell of a strombid has a long and narrow aperture and a siphonal canal. The shell margin has an indentation near the anterior end which accommodates one of the eye stalks. This indentation is called a strombid or stromboid notch. The stromboid notch may be more or less conspicuous, depending on the species. [6] The shells of most species in this family grow a flared lip upon reaching sexual maturity. They lay eggs in long, gelatinous strands. The genera Strombus and Lambis have many similarities between them, both anatomical and reproductive, though their shells show some conspicuous differences.
Strombids were widely accepted as carnivores by several authors in the 19th century, an erroneous concept that persisted for several decades into the first half of the 20th century. This ideology was probably born in the writings of Lamarck, who classified strombids alongside other supposedly carnivorous snails, and was copied in this by subsequent authors. However, the many claims of those authors were never supported by the observation of animals feeding in their natural habitat. [7] Nowadays, strombids are known to be specialized herbivores and occasional detritivores. They are usually associated with shallow-water reefs and seagrass meadows. [8]
Unlike most snails, which glide slowly across the substrate on their feet, strombid gastropods have a characteristic means of locomotion, using their pointed, sickle-shaped, horny operculum to propel themselves forward in a so-called leaping motion. [1] [9]
Burrowing behavior, in which an individual sinks itself entirely or partially into the substrate, is also frequent among strombid gastropods. The burrowing process itself, which involves distinct sequential movements and sometimes complex behaviors, is very characteristic of each species. Usually, large strombid gastropods, such as the queen conch Eustrombus gigas and the spider conch Lambis lambis , do not bury themselves, except during their juvenile stages. However, smaller species such as Strombus canarium and Strombus epidromis may bury themselves even after adulthood. [10]
For a long time, all conchs and their allies (the strombids) were classified in only two genera, namely Strombus and Lambis. This classification can still be found in many textbooks and on websites on the internet. Based on molecular phylogeny [8] in addition to an extensively documented fossil record, both genera have been subdivided into several new genera by different authors. [5] [11] [12]
The family Strombidae actually comprises 26 extant genera and 10 extinct genera (marked with a dagger †). [11] [13]
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Phylogeny and relationships of the Strombidae according to Simone (2005) [6] |
The most recent revision of Maxwell 2019 (ZooKeys 867:1-7) new crown clade Neostromboidae to separate the Strombidae, Rostellariidae, and Seraphsidae from their sister families Struthiolariidae and Aporrhaidae. There is significant value to understanding evolutionary processes within Stromboidea to recognise the universal similarity in the position of the eye on the end of peduncles and a diminished cephalic tentacle that arises from the middle to the end on that peduncle. This is in contrast to other members of the Stromboidea where the eye is located at the base of the cephalic tentacle. These physiological differences represent two set of organisms with divergent and independent evolutionary life histories and therefore these differences need to be identifiable within the nomenclature to bring meaning to the way we name things.new crown clade Neostromboidae to separate the Strombidae, Rostellariidae, and Seraphsidae from their sister families Struthiolariidae and Aporrhaidae. There is significant value to understanding evolutionary processes within Stromboidea to recognise the universal similarity in the position of the eye on the end of peduncles and a diminished cephalic tentacle that arises from the middle to the end on that peduncle. This is in contrast to other members of the Stromboidea where the eye is located at the base of the cephalic tentacle. (from Maxwell et al. 2019) (https://www.researchgate.net/publication/334746905_Recognising_and_defining_a_new_crown_clade_within_Stromboidea_Rafinesque_1815_Mollusca_Gastropoda)
Historically the phylogenetic relationships among the Strombidae have been mainly accessed on two occasions, using two methods. In a 2005 monograph, Simone proposed a cladogram (a tree of descent) based on an extensive morpho anatomical analysis of representatives of the Aporrhaidae, Strombidae, Xenophoridae, and Struthiolariidae. [6] In his analysis, Simone recognized the Strombidae as a monophyletic taxon supported by 13 synapomorphies (traits that are shared by two or more taxa and their most recent common ancestor), comprising at least eight distinct genera. He considered the genus Terebellum as the most basal taxon, distinguished from the remaining strombids by 13 synapomorphies, including a rounded foot. [6] Though the genus Tibia was left out of the analysis, Simone regarded it as probably closely related to Terebellum , apparently due to some well known morphological similarities between them. [6] With the exception of Lambis, the remaining taxa were previously allocated within the genus Strombus . However, according to Simone, only Strombus gracilior , Strombus alatus , and Strombus pugilis , the type species, remained within Strombus, as they constituted a distinct group based on at least five synapomorphies. [6] The remaining taxa were previously considered as subgenera, and were elevated to genus level by Simone in the end of his analysis. The genus Eustrombus (now considered a synonym of Lobatus ), [11] in this case, included Eustrombus gigas (now considered a synonym of Lobatus gigas ) and Eustrombus goliath (= Lobatus goliath ); similarly, the genus Aliger included Aliger costatus (= Lobatus costatus ) and Aliger gallus (= Lobatus gallus ). [6] [11]
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Phylogeny and relationships of Strombidae according to Latiolais (2006) [8] |
A different approach, this time based on sequences of nuclear histone H3 and mitochondrial cytochrome-c oxidase I (COI) genes was proposed by Latiolais and colleagues in a 2006 paper. The analysis included 32 strombid species that used to, or still belong in the genera Strombus and Lambis. [8]
Snails in the family Strombidae are used by humans in a wide range of ways, mostly as food or decoration. Several species belonging to numerous genera among the Strombidae are considered economically important. Some species have been used in human culture for centuries. Since before the Age of Discovery, strombid shells were used as wind instruments, [14] and were later used in the lime industry, in handicrafts, as souvenirs, and even in jewelry. In the Caribbean, Bermuda and southeastern United States, the queen conch Aliger gigas is sought after for its conch pearls, which have been used in jewelry since the Victorian era. [15]
Aliger gigas, originally known as Strombus gigas or more recently as Lobatus gigas, commonly known as the queen conch, is a species of large sea snail, a marine gastropod mollusc in the family of true conches, the Strombidae. This species is one of the largest molluscs native to the Caribbean Sea, and tropical northwestern Atlantic, from Bermuda to Brazil, reaching up to 35.2 centimetres (13.9 in) in shell length. A. gigas is closely related to the goliath conch, Lobatus goliath, a species endemic to Brazil, as well as the rooster conch, Aliger gallus.
Strombus is a genus of medium to large sea snails, marine gastropod molluscs in the family Strombidae, which comprises the true conchs and their immediate relatives. The genus Strombus was named by Swedish Naturalist Carl Linnaeus in 1758. Around 50 living species were recognized, which vary in size from fairly small to very large. Six species live in the greater Caribbean region, including the queen conch, Strombus gigas, and the West Indian fighting conch, Strombus pugilis. However, since 2006, many species have been assigned to discrete genera. These new genera are, however, not yet found in most textbooks and collector's guides.
The Stromboidea, originally named the Strombacea by Rafinesque in 1815, is a superfamily of medium-sized to very large sea snails in the clade Littorinimorpha.
Lambis is a genus of large sea snails sometimes known as spider conchs, marine gastropod mollusks in the family Strombidae, the true conch family.
Laevistrombus canarium is a species of edible sea snail, a marine gastropod mollusc in the family Strombidae. 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.
Lobatus raninus, common name the hawk-wing conch, is a species of medium to large sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Lobatus is a genus of very large sea snails, marine gastropod mollusks in the family Strombidae, the true conchs. Some of the species within this genus were previously placed in the genus Eustrombus.
Titanostrombus goliath, previously known as Lobatus goliath and Strombus goliath, common name the goliath conch, is a species of very large edible sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs. T. goliath is one of the largest mollusks of the Western Atlantic Ocean, and also one of the largest species among the Strombidae. It was once considered endemic to Brazil, but specimens have also been recently found in the waters of Barbados. Brazilian common names for this species include búzio de chapéu or búzio, and búzio de aba or buzo in. Some phylogenetic hypotheses consider T. goliath as closely related to the queen conch, Aliger gigas.
Macrostrombus costatus, formerly known as Strombus costatus and Lobatus costatus, or commonly known as the milk conch, is a species of large sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs. They are an edible species and important food source for the inhabitants of where they are found. Conchs are most notable for their medium to large-sized ornamental shells. Milk conchs are dispersed among the tropical waters of the Atlantic Ocean, along the coasts and islands of North, Central, and South America.
Aliger gallus, previously known as Strombus gallus, common name the rooster conch or rooster-tail conch, is a species of medium-sized sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Labiostrombus epidromis, common name the swan conch, is a species of sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Canarium scalariforme is a species of sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Canarium labiatum, common name the Samar Conch, is a species of sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Canarium mutabile, common name the variable stromb, is a species of sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Sinustrombus sinuatus, common name the laciniate conch, is a species of sea snail, a marine gastropod mollusc in the true conch family, Strombidae. It is native to the tropical Indo-Pacific region.
Canarium urceus is a species of sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Aliger is a genus of sea snails, marine gastropod mollusks in the family Strombidae, the true conchs.
Canarium is a genus of sea snails, marine gastropod mollusks in the family Strombidae, the true conchs.
Strombus gracilior, common names the Eastern Pacific fighting conch, or the Panama fighting conch, is a species of medium to large sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.
Titanostrombus galeatus, commonly known as the Eastern Pacific giant conch, is a species of large sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs and their allies.