The complete sequences of three mitochondrial genomes from the land snailCornu aspersumwere determined. The mitogenome has a length of 14050 bp, and it encodes 13 protein-coding genes, 22 transfer RNA genes and two ribosomal RNA genes. It also includes nine small intergene spacers, and a large AT-rich intergenic spacer. The intra-specific divergence analysis revealed thatCOX1has the lower genetic differentiation, while the most divergent genes wereNADH1,NADH3andNADH4. With the exception ofEuhadra herklotsi, the structural comparisons showed the same gene order within the family Helicidae, and nearly identical gene organization to that found in order Pulmonata. Phylogenetic reconstruction recovered Basommatophora as polyphyletic group, whereas Eupulmonata and Pulmonata as paraphyletic groups. Bayesian and Maximum Likelihood analyses showed thatC. aspersumis a close relative ofCepaea nemoralis, and with the other Helicidae species form a sister group ofAlbinaria caerulea, supporting the monophyly of the Stylommatophora clade.
Cornu aspersum, beter bekend onder sy algemene naam tuinslak, is 'n spesie van 'n landslak. As sodanig is dit 'n landwonende pulmonate gastropoot in die familie Helicidae, wat insluit die mees algemeen bekende landslakke. Van al die landwonende weekdiere, is hierdie spesie waarskynlik die meesbekende. In Engels tekse was die slak geklassifiseer onder die naam Helix aspersa vir meer as twee eeue, maar die huidige klassifikasie plaas dit in die genus Cornu.
Cornu aspersum is inheems aan die Middellandse Seegebied en Wes-Europa, maar hetsy doelbewus of per ongeluk, het die mens dit versprei na die gematigde en subtropiese gebiede wêreldwyd. Die slak word genuttig as 'n delikatessen in sommige gebiede, maar dit word ook oral as 'n plaag beskou in tuine en in die landbou, veral in gebiede waar dit per ongeluk ingevoer is, en waar die slakke gewoonlik nie as 'n menu-item beskou word nie.
Hierdie slakke word tipies gevind nadat dit gereën het of rondom skemer. Tydens warm weer sal hierdie hermafrodiete egter gewoonlik verborge bly. In voorstedelike gebiede word hulle algemeen gevind terwyl hulle voed op grasperke en in blombeddings, na die grasperk se sprinkelstelsel hierdie dele met water deurweek het na sononder.
Cornu aspersum, beter bekend onder sy algemene naam tuinslak, is 'n spesie van 'n landslak. As sodanig is dit 'n landwonende pulmonate gastropoot in die familie Helicidae, wat insluit die mees algemeen bekende landslakke. Van al die landwonende weekdiere, is hierdie spesie waarskynlik die meesbekende. In Engels tekse was die slak geklassifiseer onder die naam Helix aspersa vir meer as twee eeue, maar die huidige klassifikasie plaas dit in die genus Cornu.
Cornu aspersum is inheems aan die Middellandse Seegebied en Wes-Europa, maar hetsy doelbewus of per ongeluk, het die mens dit versprei na die gematigde en subtropiese gebiede wêreldwyd. Die slak word genuttig as 'n delikatessen in sommige gebiede, maar dit word ook oral as 'n plaag beskou in tuine en in die landbou, veral in gebiede waar dit per ongeluk ingevoer is, en waar die slakke gewoonlik nie as 'n menu-item beskou word nie.
Hierdie slakke word tipies gevind nadat dit gereën het of rondom skemer. Tydens warm weer sal hierdie hermafrodiete egter gewoonlik verborge bly. In voorstedelike gebiede word hulle algemeen gevind terwyl hulle voed op grasperke en in blombeddings, na die grasperk se sprinkelstelsel hierdie dele met water deurweek het na sononder.
Cornu aspersum a zo ur spesad maligorned hag a vez renket er genad Cornu e kerentiad an Helicidae. Ur spesad mat da zebriñ eo hag an aesañ da sevel evit ar bevezerezh. Graet e voe gantañ dindan an anv spesad Helix aspersa e-pad tost da zaou gantved.
a vo kavet e Wikimedia Commons.
Cornu aspersum a zo ur spesad maligorned hag a vez renket er genad Cornu e kerentiad an Helicidae. Ur spesad mat da zebriñ eo hag an aesañ da sevel evit ar bevezerezh. Graet e voe gantañ dindan an anv spesad Helix aspersa e-pad tost da zaou gantved.
Die Gefleckte Weinbergschnecke (Cornu aspersum) ist in Mitteleuropa weniger bekannt als ihre große Verwandte, die Weinbergschnecke (Helix pomatia). Grund dafür mag in erster Linie das Verbreitungsgebiet dieser Art sein, denn sie bevorzugt milderes Klima, d. h. den Mittelmeerraum und die atlantischen Küstengebiete. Allerdings wurde sie durch Verschleppung weit verbreitet, so dass sie heute in Südafrika, Neuseeland, Nordamerika und Australien zu finden ist.
Die Gefleckte Weinbergschnecke ist am besten im Vergleich zur Helix pomatia zu beschreiben. Setzt man zwei ausgewachsene Tiere beider Arten nebeneinander, so ist deutlich zu erkennen, dass die Schale der Gefleckten Weinbergschnecke etwas kleiner bleibt als die der Helix pomatia. Die Gefleckte Weinbergschnecke erreicht vom Apex zur Gehäusemündung gemessen höchstens eine Größe von etwa 4 cm, während bei der Helix pomatia etwa 5 cm Durchschnitt und 6 cm möglich sind.
Färbung und Oberfläche der Schale unterscheiden sich mitunter stark voneinander, denn die Schale von Cornu aspersum ist rau, geradezu „runzlig“ und von einem charakteristischen Muster bedeckt, das der Gefleckten Weinbergschnecke ihren Namen gegeben hat. Das Muster aus dunkelbraunen Streifen und Karo-Mustern auf hellem, hornfarbenem bis bräunlichen Grund, (ähnlich dem der einheimischen Gefleckten Schnirkelschnecke) verleiht der gesamten Schale ein eher dunkleres Aussehen.
Der Weichkörper selbst ist meist hellgrau bis schwarz gefärbt, wobei deutlich ein etwas dunklerer Aalstrich zu erkennen ist. Im Vergleich zu Helix pomatia ist die Furchung der Fußoberseite weit weniger tief und deutlich abgezeichnet.
In ihren Anforderungen an den Lebensraum sind die Gefleckten Weinbergschnecken relativ tolerant. Das zeigt sich nicht nur in ihrer weiten Ausbreitung, sondern vor allem in der Vielfalt der von ihnen besiedelten Lebensräume. Tatsächlich ist Cornu aspersum bis in Höhen von 1000 m über dem Meeresspiegel zu finden und besiedelt Heiden und Wiesen ebenso wie Wälder, Gärten, Parkanlagen, Dünen und felsige Gebiete.
Diese Toleranz liegt mitunter daran, dass die Gefleckte Weinbergschnecke aufgrund ihrer kleineren Schale und der fehlenden Notwendigkeit eines Überwinterungsdeckels (Epiphragma) weniger an kalkhaltigen Boden gebunden ist als ihre große Verwandte.
Früher war die Gefleckte Weinbergschnecke nur im Mittelmeerraum zu finden, Grund dafür ist unter anderem, dass die Gefleckte Weinbergschnecke anders als Helix pomatia keinen dicken Kalkdeckel ausbildet, mit dem sie ihre Gehäuseöffnung den Winter über als Schutz vor Kälte und Trockenheit verschließen kann. Stattdessen überzieht sie die Gehäuseöffnung mit einem dünnen Schleimhäutchen, das sich an der Luft festigt. Temperaturen unter 5 °C sind für die Gefleckte Weinbergschnecke ungeeignet. Im Zuge der Klimaerwärmung findet man sie zunehmend in Mitteleuropa.
Weinbergschnecken sind ausschließlich Pflanzenfresser, wobei sie welkes Pflanzenmaterial meist frischen Pflanzen bevorzugen. Dieses raspeln sie mit einer Raspelzunge, der Radula, ab. Im Garten ist das Vorhandensein von Helix apersa gewöhnlich kein Problem.
Die Tiere sind überwiegend nachtaktiv. Im Winter fallen sie in eine Kältestarre, in der die Bewegungen und Grundfunktionen auf ein Minimum reduziert werden. Hierbei deckelt sich die gefleckte Weinbergschnecke im Gegensatz zur Helix pomatia ihr Gehäuse nicht mit einem Kalkdeckel ab, sondern schützt sich mit einer dünnen Membran aus eingetrocknetem Schleim vor der Kälte.
Die Gefleckte Weinbergschnecke ist Zwitter (Hermaphrodit), das heißt jedes Individuum besitzt sowohl männliche als auch weibliche Geschlechtsorgane und kann somit beim Paarungsakt sowohl als Männchen als auch als Weibchen fungieren. Beim Liebesspiel pressen beide Partner die Fußsohlen aneinander – das kann sowohl in liegender Stellung wie bei mitteleuropäischen Baum- und Gartenschnecken, als auch in erhobener Position, wie es bei Helix pomatia üblich ist geschehen. Zur Anregung stoßen sich die Partner gegenseitig so genannte „Liebespfeile“ aus Kalk in den Fuß. Dadurch wird dem Partner ein Hormonsekret injiziert. Der Penis einer Gefleckten Weinbergschnecke ist deutlich anders geformt als der einer gewöhnlichen Weinbergschnecke.
Cornu aspersum legt wie die Helix pomatia ihre Eier in selbstgegrabenen Erdhöhlen ab, aus denen nach wenigen Wochen vollständig entwickelte Jungschnecken samt Schale schlüpfen, die noch einige Zeit im Erdreich verharren, bis sie kräftig genug sind, an die Oberfläche zu stoßen (ca. 15–20 Tage).
Die Gefleckte Weinbergschnecke wurde 1774 von Otto Friedrich Müller als Helix aspersa beschrieben. Aufgrund von Unterschieden an der Schale und im Bau der Genitalien wurde die Art schon zu Beginn des 20sten Jahrhunderts als von Helix verschieden erkannt. Allerdings erfolgte die Abtrennung nur auf Untergattungsniveau. Erst gegen Ende des 20sten Jahrhunderts stellte man die Art vermehrt in eine eigenständige Gattung Cryptomphalus oder fasste sie mit der Grunzschnecke zur Gattung Cantareus zusammen[2][3]. Die Bezeichnung Helix aspersa wird allerdings auch heute noch häufig verwendet, obwohl sich mittlerweile auch in molekulargenetischen Studien bestätigt hat, dass die Gefleckte Weinbergschnecke nur sehr entfernt mit den eigentlichen Weinbergschnecken verwandt ist[4][5].
Der Gattungsname Cornu wurde von Ignaz von Born 1778 eingeführt. Da dieser Name allerdings auf einer missgebildete Schale basiert, wurde zumeist angenommen, dass er nicht verwendet werden kann. Deshalb wurde die Art hauptsächlich als Cryptomphalus aspersus bezeichnet. Die Internationale Kommission für Zoologische Nomenklatur urteilte 2015[6], dass der Name Cornu verfügbar ist. Der korrekte wissenschaftliche Name der Gefleckten Weinbergschnecke lautet deshalb Cornu aspersum.
Cornu aspersum findet ihre Bedeutung für den Menschen (wie auch Helix pomatia) hauptsächlich in der Zucht zu Speisezwecken. Hierzu wird sie in Schneckenfarmen meist im französischen Burgund in Terrarien oder auch Aussengehegen gezüchtet. In den französischen Schneckenzuchten stellt die Gefleckte Weinbergschnecke im Vergleich zur gewöhnlichen Weinbergschnecke sogar den weit größeren Teil an Zuchttieren dar. Hierzu wurden eigene Züchtungen entwickelt, die zum Teil doppelt so schwer werden wie die ursprünglichen Schnecken.
Darüber hinaus wird die Gefleckte Weinbergschnecke, ähnlich wie Afrikanische Riesenschnecken, immer beliebter als Heimtier (vor allem in England).
Die Gefleckte Weinbergschnecke ist Zwischenwirt für den Katzen-Lungenwurm Aelurostrongylus abstrusus und ein Faktor für die zunehmende Verbreitung der Aelurostrongylose.[7]
Junge Gefleckte Weinbergschnecken auf einem Salatblatt.
Gefleckte Weinbergschnecke von vorne.
Gefleckte Weinbergschnecke beim Abkoten
Seltene linksgewundene Form, sogenannter „Schneckenkönig“, und normale rechtsgewundene Form; Häufigkeit links- zu rechtsgewunden: 1:40 000.[8]
Die Gefleckte Weinbergschnecke (Cornu aspersum) ist in Mitteleuropa weniger bekannt als ihre große Verwandte, die Weinbergschnecke (Helix pomatia). Grund dafür mag in erster Linie das Verbreitungsgebiet dieser Art sein, denn sie bevorzugt milderes Klima, d. h. den Mittelmeerraum und die atlantischen Küstengebiete. Allerdings wurde sie durch Verschleppung weit verbreitet, so dass sie heute in Südafrika, Neuseeland, Nordamerika und Australien zu finden ist.
Cornu aspersum (syn. Cryptomphalus aspersus), known by the common name garden snail, is a species of land snail in the family Helicidae, which includes some of the most familiar land snails. Of all terrestrial molluscs, this species may well be the most widely known. It was classified under the name Helix aspersa for over two centuries, but the prevailing classification now places it in the genus Cornu.
The snail is relished as a food item in some areas, but it is also widely regarded as a pest in gardens and in agriculture, especially in regions where it has been introduced accidentally, and where snails are not usually considered to be a menu item.
The adult bears a hard, thin calcareous shell 25–40 millimetres (1–1+5⁄8 in) in diameter and 25–35 millimetres (1–1+3⁄8 in) high, with four or five whorls. The shell is variable in coloring and shade of color, but generally it has a reticulated pattern of dark brown, brownish-golden, or chestnut with yellow stripes, flecks, or streaks (characteristically interrupted brown colour bands). The aperture is large and characteristically oblique, its margin in adults is whitish and reflected.
The body is soft and slimy, brownish-grey, and able to be retracted entirely into the shell, which the animal does when inactive or threatened. When injured or badly irritated the snail produces a defensive froth of mucus that might repel some enemies or overwhelm aggressive small ants and the like. It has no operculum; during dry or cold weather it seals the aperture of the shell with a thin membrane of dried mucus; the term for such a membrane is epiphragm. The epiphragm helps the snail retain moisture and protects it from small predators such as some ants.
The snail's quiescent periods during heat and drought are known as aestivation; its quiescence during winter is known as overwintering. When overwintering, Cornu aspersum avoids the formation of ice in its tissues by altering the osmotic components of its blood (or haemolymph); this permits it to survive temperatures as low as −5 °C (23 °F).[4] During aestivation, the mantle collar has the ability to change its permeability to water.[5] The snail also has an osmoregulatory mechanism that prevents excessive absorption of water during hibernation. These mechanisms allow Cornu aspersum to avoid either fatal desiccation or hydration during months of either kind of quiescence.
During times of activity the snail's head and "foot" emerge. The head bears four tentacles; the upper two are larger and bear eye-like light sensors, and the lower two are tactile and olfactory sense organs. The snail extends the tentacles by internal pressure of body fluids, and retracts all four tentacles into the head by invagination when threatened or otherwise retreating into its shell. The mouth is located beneath the tentacles, and contains a chitinous radula with which the snail scrapes and manipulates food particles.
The shell of Cornu aspersum is almost always right-coiled, but exceptional left-coiled specimens are also known; see Jeremy (snail) for an example.
The accepted name of the species was long considered to be Helix aspersa, a member of the genus Helix. However, in a number of publications since 1990,[6] it has instead been placed in various genera previously considered as subgenera of Helix. One such genus is Cornu, which is appropriate if the species is considered as congeneric with the species previously known as Helix aperta.[7][8] Then the name would be Cornu aspersum.[9][10][11] Previously there was debate whether Cornu was a valid generic name (because it was first applied to teratological specimens), but a 2015 ruling has confirmed that it is so.[12] Until this was established, Italian research teams and others used the generic name Cantareus instead.[13][14][15][16] Other workers, including Ukrainian and Russian research teams, who regard H. aspersa and H. aperta as being in different genera, call the former Cryptomphalus aspersus.[17][18][19][20] It also still remains an arguable position to retain Helix as the generic name.[21]
Many subspecific varieties have been described on the basis of shell characters (e.g.[22]). The most prominent example nowadays is the subspecies Cornu aspersum maximum (Taylor, 1883),[23] originally described as a large shelled form from Algeria (but perhaps including similar forms from elsewhere). In the recent scientific literature the name has been applied both to large Algerian snails[24] and to a large form found in snail farms.[25] Some Algerian forms are indeed genetically quite distant from the usual, most widespread form, but the large form in snail farms is different again.[26][25] It is also problematic that there was a prior use of the name Helix aspersa maxima unassociated with Algeria.[27] The subspecies maximum is formally considered by some authorities as a junior synonym of Cornu aspersum.[28][29]
Like other Pulmonata, individuals are hermaphrodites, producing both male and female gametes. Reproduction is predominantly, and probably exclusively, by outcrossing.[30][31] During a mating session of several hours, two snails exchange sperm reciprocally. H. aspersa snails stab a calcite spine, known as a love dart, at their partner. The love dart is coated with a mucus that contains a chemical that enables more sperm to survive inside the recipient. Individuals mate repeatedly between oviposition events and can store viable allosperm for 4 years.[31][32] About 10 days after fertilisation, the snail lays a batch of on average 50 spherical pearly-white eggs into crevices in the topsoil, or sheltered under stones or the like.[30] In a year it may lay approximately six batches of eggs.[33] The size of the egg is 3 mm.[30]
After snails hatch from the egg, they mature in one or more years, depending on where the organism lives. Maturity takes two years in Southern California, while it takes only 10 months in South Africa. In captivity snails can become sexually mature within 3.5 months of hatching, before they stop growing.[30] The lifespan of snails in the wild is typically 2–3 years.
Cornu aspersum is native to the Mediterranean region and its present range stretches from northwest Africa and Iberia, eastwards to Asia Minor and Egypt,[34] and northwards to Britain.[35]
Cornu aspersum is a typically anthropochorous species; it has been spread to many geographical regions by humans, either deliberately or accidentally. Nowadays it is cosmopolitan in temperate zones, and has become naturalised in regions with climates that differ from the mediterranean climate in which it evolved.[36][37] Its passive anthropochory is the likeliest explanation for genetic resemblances between allopatric populations. Its anthropochorous spread may have started as early as during the Neolithic revolution some 8500 BP. Such anthropochory continues, sometimes resulting in locally catastrophic destruction of habitat or crops.[38]
Its increasing non-native distribution includes parts of Europe, such as Bohemia in the Czech Republic since 2008.[39] It is present in Australia, New Zealand, North America, Costa Rica [40] and southern South America.[41] It was introduced to Southern Africa as a food animal by Huguenots in the 18th century, and into California as a food animal in the 1850s; it is now a notorious agricultural pest in both regions, especially in citrus groves and vineyards. Many jurisdictions have quarantines for preventing the importation of the snail in plant matter.[42]
A number of North African endemic forms and subspecies have been described on the basis of shell characters. Cornu aspersum aspersum, in French commonly called the "petit gris", is native to the Mediterranean area and Western Europe, but has been spread widely elsewhere. The name Cornu aspersum maximum has been applied to a large form kept in heliculture (in French commonly called the "gros gris"), but this is genetically distinct from large Algerian forms earlier given this name.[26]
Cornu aspersum is a primarily a herbivore. It feeds on numerous types of fruit trees, vegetable crops, rose bushes, garden flowers, and cereals. It also is an omnivorous scavenger that will feed on rotting plant material and on occasion scavenge animal matter, such as crushed snails and worms. Cornu aspersum can obtain the calcium required to build its shell by consuming soil. [43] In turn it is a food source for many other animals, including small mammals, some bird species, lizards, frogs, centipedes, predatory insects such as glowworms in the family Lampyridae, and predatory terrestrial snails.[44] The species may be of use as an indicator of environmental pollution, because it deposits heavy metals, such as lead, in its shell.[45]
Parasites of Cornu aspersum include a number of nematodes.[46][47][48] Metacercariae of various species of the digenean genus Brachylaima have also been reported, and those have potential for being harmful to people because the adults can infect humans.[48] However, the snails are capable of trapping cercariae (trematode larvae) in their shell, thus possibly reducing the intensity of infestation by parasites.[49]
The snail secretes thixotropic adhesive mucus that permits locomotion by rhythmic waves of contraction passing forward within its muscular foot. Starting from the rear, the contraction of the longitudinal muscle fibres above a small area of the film of mucus causes shear that liquefies the mucus, permitting the tip of the tail to move forward. The contracted muscle relaxes while its immediately anteriad transverse band of longitudinal fibres contract in their turn, repeating the process, which continues forward until it reaches the head. At that point the whole animal has moved forward by the length of the contraction of one of the bands of contraction. However, depending on the length of the animal, several bands of contraction can be in progress simultaneously, so that the resultant speed amounts to the speed imparted by a single wave, multiplied by the number of individual waves passing along simultaneously.[50]
A separate type of wave motion that may be visible from the side enables the snail to conserve mucus when moving over a dry surface. It lifts its belly skin clear of the ground in arches, contacting only one to two thirds of the area it passes over. With suitable lighting the lifting may be seen from the side as illustrated, and the percentage of saving of mucus may be estimated from the area of wet mucus trail dabs that it leaves behind. This type of wave passes backwards at the speed of the snail's forward motion, therefore having a zero velocity with respect to the ground.
Since its publication in March 1974 issue of Natural History[51] an estimate for the highest speed of garden snail equal to 0.03 mph (1.3 cm/s) became popular.[52][53] However, the accuracy of this estimate has been questioned by Robert Cameron, who pointed out that in competitions between snails, only 2.4 mm/s speed had been achieved.[54] There is a need for clarification and behavioural observation here though: competitions are usually held on the flat, whereas a snail's natural preference is vertical ascent, possibly an instinct derived from hatching in an earth "pod" and having to climb upwards to the surface.
Cornu aspersum has a strong homing instinct, readily returning to a regular hibernation site.[55]
The species is known as an agricultural and garden pest, an edible delicacy, and occasionally a household pet. In French cuisine, it is known as petit gris, and is served for instance in Escargot a la Bordelaise. Also in Lleida, a city of Catalonia, there is a gastronomic festival called L'Aplec del Caragol dedicated to this type of snail, known as bover, and attracts over 200,000 guests every year. From Crete are known a dish called "chochloi mpoumpouristoi"(snails turned upside down), the snails cooked alive in a hot pan, on a thick layer of sea salt. Other dishes with snails are snails with rosemary, etc. The practice of rearing snails for food is known as heliciculture. For purposes of cultivation, the snails are kept in a dark place in a wired cage with dry straw or dry wood. Coppiced wine-grape vines are often used for this purpose. During the rainy period the snails come out of hibernation and release most of their mucus onto the dry wood/straw. The snails are then prepared for cooking. Their texture when cooked is slightly chewy.
There are a variety of snail-control measures that gardeners and farmers use in an attempt to reduce damage to valuable plants. Traditional pesticides are still used, as are many less toxic control options such as concentrated garlic or wormwood solutions. Copper metal is also a snail repellent, and thus a copper band around the trunk of a tree will prevent snails from climbing up and reaching the foliage and fruit. Caffeine has proven surprisingly toxic to snails, to the extent that spent coffee grounds (not decaffeinated) make a safe and immediately effective snail-repellant and even molluscicidal mulch for pot-plants, or for wherever else the supply is adequate.
Garden snails can be easily controlled and trapped with a simple trap created by cutting a plastic bottle in half and burying the bottom half so the top is level with the soil, then partially filling the bottle bottom with any variety of beer. Snails are attracted to the carbohydrates and yeast in beer, and crawl into the trap and drown. This method requires that the trap be checked every day and dead snails removed and the trap refilled with beer as it evaporates over time. Traps should be spaced every three to four meters from one another for coverage of a large garden.[57][58][59]
The decollate snail (Rumina decollata) will capture and eat garden snails, and because of this it has sometimes been introduced as a biological pest control agent.[60] However, this is not without problems, as the decollate snail is just as likely to attack and devour other species of gastropods that may represent a valuable part of the native fauna of the region.
Cornu aspersum has gained some popularity as the chief ingredient in skin creams and gels (crema/gel de caracol) sold in the US. These creams are promoted as being suitable for use on wrinkles, scars, dry skin, and acne to reduce pigmentation, scarring, and wrinkles.[61]
Secretions of Cornu aspersum produced under stress have skin-regenerative properties because of antioxidant superoxide dismutase and glutathione S-transferase (GSTs) activities. The secretions can stimulate fibroblast proliferation and rearrange the actin cytoskeleton stimulate extracellular matrix assembly and regulation of metalloproteinase activities for regeneration of wounded tissue.[62]
The mucus of Cornu aspersum contains a rich source of substances that can be used to treat biotic human diseases. Nine fractions of compounds with varying molecular weight were purified from the mucus and was tested against gram-positive and gram-negative bacterial strains. Results found three fractions exhibited predominant antibacterial activity against the gram-positive strain.[63]
This article incorporates CC-BY-2.0 text from reference.[38]
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Cornu aspersum (syn. Cryptomphalus aspersus), known by the common name garden snail, is a species of land snail in the family Helicidae, which includes some of the most familiar land snails. Of all terrestrial molluscs, this species may well be the most widely known. It was classified under the name Helix aspersa for over two centuries, but the prevailing classification now places it in the genus Cornu.
The snail is relished as a food item in some areas, but it is also widely regarded as a pest in gardens and in agriculture, especially in regions where it has been introduced accidentally, and where snails are not usually considered to be a menu item.
El caracol común de jardín o burgajo (Helix aspersa) es una especie de molusco gasterópodo pulmonado de la familia Helicidae, de vida terrestre. Es una de las varias especies del género Helix, muy similares. No debe confundirse con Helix pomatia, el caracol romano, otra de las especies más abundantes.
Existe controversia sobre el nombre científico de esta especie; otros nombres usados para denominarla son Cryptomphalus aspersus, Cornu aspersum y Cantareus aspersus.[1]
Es originario de Europa, pero vive en muchas otras zonas. Su cuerpo es de hasta 8 cm de largo. Es de hábitos crepusculares y nocturnos, aunque en lugares húmedos en penumbra y en días de lluvia también es activo de día. En época de sequía se esconde dentro de la concha y se encierra elaborando un "tapón" a base de moco seco llamado epifragma.
Como la mayoría de las babosas y caracoles, posee órganos masculinos y femeninos, por lo que cualquier pareja de individuos puede procrear. Es hermafrodita, ovíparo y posee una concha calcárea enrollada en espiral. Famoso por su proverbial lentitud, se mueve a una velocidad máxima de 0,05 km/h,[2][3] a pesar de lo cual es uno de los caracoles más rápidos.
Tanto en Europa como en las regiones en las que se ha introducido accidentalmente, este caracol es una plaga de los cultivos que puede provocar graves pérdidas económicas; el uso excesivo de plaguicidas para su control tiene efectos perjudiciales sobre el medio ambiente y sobre la salud humana, por la contaminación de aguas y suelos y por la presencia de trazas en vegetales de consumo humano. Ante esta problemática económica, sanitaria y ambiental, la Universidad de Santiago de Compostela viene liderando desde el año 2009 el Proyecto Europeo FP7:[4] control de plagas, que pretende diseñar nuevas estrategias para el control integrado de plagas de caracoles terrestres en Europa (Arion lusitanicus, Deroceras reticulatum, Lehmannia marginata, Milax gagates, Criptophalus aspersus, Theba pisana), con proyección a Latinoamérica y Egipto. Participan como socios de la USC, investigadores de Noruega, Francia, Inglaterra, Escocia, Holanda, Suiza, Egipto, Colombia, Brasil, Ecuador, Perú, Argentina, Chile y Costa Rica. Según la USC, el 90% de caracoles terrestres que son plagas de cultivos en Latinoamérica son especies introducidas, mayormente de Europa, que proliferan sin control debido a la ausencia de predadores.
Dado que el comercio internacional puede facilitar la dispersión del caracol Helix aspersa a través de embarques de productos agrícolas, muchos países han adoptado rigurosas medidas sanitarias para evitar la introducción de la especie y proteger sus cultivos. Por ejemplo, Canadá y Estados Unidos incluyen a la especie en sus listas de plagas[5] de interés cuarentenario. De hecho, el caracol de jardín es la especie más interceptada por el USDA en puertos fronterizos. En el mismo sentido, el Organismo Internacional Regional de Sanidad Agropecuaria OIRSA[6] ha publicado un documento técnico[7] dirigido a las autoridades aduaneras de los países miembros (México, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica y Panamá), en donde llama la atención sobre los daños que ocasionan caracoles y babosas de tierra en jardines, huertos, viveros, invernaderos, cafetales, plantaciones de cacao, y áreas dedicadas a producción hortícola, instando a las autoridades aduaneras a ejercer un estricto control para evitar su dispersión.
Además de su impacto como plaga agrícola, el caracol de jardín, al igual que otras especies animales criadas por el hombre (cerdos, conejos, truchas, tilapias), tiene un alto potencial de convertirse en una especie invasora cuando es liberado de forma intencional o accidental en ambientes naturales, hecho que está documentado en vastas zonas del planeta.
Una completa revisión bibliográfica al respecto se encuentra en la tesis de grado The Invasive Potential of the Brown Garden Snail (Cantareus aspersus),[8] publicada por la Universidad de Copenhague. Los investigadores identificaron la presencia de Helix aspersa en cincuenta y tres países alrededor del mundo, de los cuales treinta y dos la reportan como introducida y seis como invasora (Brasil, Estados Unidos, Nueva Zelanda, Australia, Ecuador y Sudáfrica). A esta lista debe agregarse Colombia, que mediante Resolución 848 de 2008,[9] expedida por el Ministerio de Ambiente, declaró al caracol de jardín como especie invasora en su territorio nacional.
A nivel de Latinoamérica, en el marco de la Estrategia Regional de Biodiversidad para los Países del Trópico Andino, se publicó en el año 2001 un documento técnico[10] que registra a la especie H. aspersa como plaga de Colombia, Ecuador, Perú y Venezuela.
El Instituto HORUS para la Conservación y el Desarrollo del Medio Ambiente, prestigiosa ONG que trabaja en asocio con The Nature Conservancy, maneja la base de datos de especies invasoras de Brasil, la cual incluye una ficha[11] para el caracol de jardín. El Instituto Humboldt, centro de investigación adscrito al Ministerio de Ambiente de Colombia, tiene una ficha[12] similar para esta especie, resaltando su estatus de invasora y plaga agrícola. Por este motivo, la cría comercial de Helix aspersa en Colombia ha sido cuestionada en libros,[13] prensa escrita[14][15][16] y revistas especializadas.[17]
Este gasterópodo es muy apreciado en gastronomía mediterránea; en especial en Francia, llamado petit gris, y en Cataluña, conocido como bover. En la ciudad de Lérida cada año se celebra el Aplec del Caragol, una fiesta popular dedicada a esta variedad de caracol con más de doscientos mil visitantes y unas doce toneladas de caracoles ingeridos. La particularidad gastronómica que diferencia esta variedad de caracol es el sabor y la textura de su baba, también utilizada en productos de cosmética. Para su consumo, se recolecta o se cría en granjas especiales. La cría de caracoles se llama helicicultura.
El caracol común de jardín o burgajo (Helix aspersa) es una especie de molusco gasterópodo pulmonado de la familia Helicidae, de vida terrestre. Es una de las varias especies del género Helix, muy similares. No debe confundirse con Helix pomatia, el caracol romano, otra de las especies más abundantes.
Barraskilo arrunta (Helix aspersa) tamaina handiko barraskilo espeziea da, beraz molusku gasteropodo lurtarra. Europa osoan bizi da eta jateko ona da (izan ere, helizikulturan oso aintzat hartua dute). Frantzian jaten duten Helix pomatia (escargot) oso antzekoa du.
Artikulu hau biologiari buruzko zirriborroa da. Wikipedia lagun dezakezu edukia osatuz. Barraskilo arrunta (Helix aspersa) tamaina handiko barraskilo espeziea da, beraz molusku gasteropodo lurtarra. Europa osoan bizi da eta jateko ona da (izan ere, helizikulturan oso aintzat hartua dute). Frantzian jaten duten Helix pomatia (escargot) oso antzekoa du.
L'escargot petit-gris (Helix aspersa) est une espèce de mollusques gastéropodes terrestres de la famille des Helicidae et du genre Helix.
Coquille brun doré portant des bandes brunes interrompues de façon caractéristique. Sa taille est de 30-35 et 32-40 mm.
Il vit dans les broussailles et les couverts légers en terrain ouvert et dans les dunes. Souvent dans les terrains cultivés.
Région méditerranéenne, côte atlantique, et jusqu'en Hollande. Introduit depuis l'Antiquité en Grèce, dans les îles britanniques et en Europe centrale. De nos jours mondialement répandu.
Il se nourrit d'herbes et peut occasionner quelques dégâts rarement importants dans les jardins.
En France il pond entre mai et fin octobre de 50 à 110 œufs d'un diamètre de 4 à 4,5 mm agglomérés par une masse visqueuse. La ponte a lieu 5 à 8 jours après l'accouplement.
L'éclosion se produit en 15 à 30 jours et il atteint sa maturité sexuelle en 2 ans.
Il peut vivre 4 ans.
L'espèce a été décrite par le zoologiste danois Otto Friedrich Müller en 1774[1].
Liste des sous-espèces :
L'escargot petit-gris (Helix aspersa) est une espèce de mollusques gastéropodes terrestres de la famille des Helicidae et du genre Helix.
Garðabobbi (fræðiheiti: Cornu aspersum) er landsnigill í lyngbobbaætt (Helicidae). Hann hefur gengið undir fræðiheitinu Helix aspersa í yfir tvær aldir, en núverandi flokkun setur hann í ættkvíslina Cornu.
Cornu aspersum er ættaður frá Miðjarðarhafssvæðinu og Vestur-Evrópu en hefur breiðst út með mönnum til tempraða og heittempraða beltisins, annað hvort sem slæðingur eða sem nytjategund. Snigillinn er víða nýttur til matar en er einnig víða talinn plága í görðum og ræktun, sérstaklega þar sem hann er ekki nýttur.
Hann hefur fundist á fáeinum stöðum á Íslandi.[2]
Þessi grein inniheldur CC-BY-2.0 texta úr tilvísun.[3]
Garðabobbi (fræðiheiti: Cornu aspersum) er landsnigill í lyngbobbaætt (Helicidae). Hann hefur gengið undir fræðiheitinu Helix aspersa í yfir tvær aldir, en núverandi flokkun setur hann í ættkvíslina Cornu.
Cornu aspersum er ættaður frá Miðjarðarhafssvæðinu og Vestur-Evrópu en hefur breiðst út með mönnum til tempraða og heittempraða beltisins, annað hvort sem slæðingur eða sem nytjategund. Snigillinn er víða nýttur til matar en er einnig víða talinn plága í görðum og ræktun, sérstaklega þar sem hann er ekki nýttur.
Hann hefur fundist á fáeinum stöðum á Íslandi.
Cornu aspersum (Müller, 1774) è un mollusco gasteropode terrestre della famiglia Helicidae. È l'unica specie nota del genere Cornu Born, 1778.[3]
Il diametro della sua conchiglia può arrivare ad un massimo di 35 mm., con una altezza di 28–32 mm; il suo peso può superare i 15 gr. L'allevamento selettivo ha portato alla comparsa di individui che superano ampiamente queste misure.
Presenta un peristoma di colore biancastro, con margine più o meno ripiegato verso l'esterno. La colorazione di fondo va dal verdastro al giallastro; può essere uniforme, ma più spesso sono presente da 1 a 5 bande spiralate marroni, più o meno marcate, con screziatura gialla o bianca.
Come molte chiocciole, C. aspersum è ermafrodita, cioè ogni individuo possiede sia organi riproduttivi maschili che femminili; non è tuttavia in grado di autofecondarsi (ermafroditismo insufficiente).
Al pari di altri elicidi gli adulti sessualmente maturi sono dotati di dardi di materiale calcareo, lunghi da 5 a 9 mm, che durante i preliminari dell'accoppiamento vengono lanciati verso il partner, trafiggendolo. Il significato funzionale di tale formazione anatomica non è ancora del tutto chiaro. Alcuni studi hanno dimostrato che un rilascio efficace del dardo si associa con un maggiore successo riproduttivo[4][5]. Osservazioni recenti puntano l'attenzione su sostanze mucose associate al dardo, rivelatesi in grado di stimolare la recettività agli spermatozoi[6].
C. aspersum è diffusa nel bacino del Mediterraneo (dalla Spagna all'Asia minore e al Nord Africa) e nell'Europa nord-occidentale (sino alle isole britanniche). In Italia è presente in tutta la penisola ed anche in Sicilia e Sardegna. L'uso in ambito alimentare ha portato alla sua introduzione e naturalizzazione in molte parti del mondo.[7][8]
Grazie alla sua resistenza e capacità di adattamento, C. aspersum è presente in diversi habitat: nelle radure, ai margini di habitat forestali, nonché in contesti antropizzati (orti, giardini, parchi, campi incolti, ruderi).
Essa è una delle chiocciole più ricercate in ambito culinario, nonché la più facile da allevare (elicicoltura).
In Francia la sottospecie C. aspersum aspersum o petit gris è stata incrociata con la sottospecie africana C. aspersum maximum o gros gris, di dimensioni quasi doppie, generando chiocciole da allevamento dalle dimensioni paragonabili a quelle della Helix pomatia di Borgogna.
In Perù è conosciuta, oltre che per gli usi alimentari, anche per le proprietà cicatrizzanti ed emollienti della bava prodotta dalle lumache stesse. In cosmetica la bava viene utilizzata per ridurre piccole cicatrici, in medicina come sciroppo per la tosse secca e recentemente, ne sono state studiate le proprietà di ridurre il dolore da ustioni profonde e migliorare la riepitelizzazione del tessuto danneggiato (Tsoutsos et all, 2009).
Negli ultimi anni sta aumentando l'applicazione della bava di lumaca in ambito cosmetico.
Cornu aspersum (Müller, 1774) è un mollusco gasteropode terrestre della famiglia Helicidae. È l'unica specie nota del genere Cornu Born, 1778.
Raiboji sraigenė (kiti pavadinimai – aptaškytoji sraigė, margoji didsraigė) (Cornu aspersum, Helix aspersa, Cryptomphalus aspersus arba Cantareus aspersus) – pilvakojų (Gastropoda) klasės sausumos sraigė, priskiriama didsraigių šeimai. Tai vienas geriausiai žinomų sausumos moliuskų, nors Vidurio Europoje nėra tokia žinoma nei jos didžioji giminaitė vynuoginė sraigė. Raiboji sraigenė natūraliai paplitusi Viduržemio jūros regione ir vakarų Europoje, tačiau sąmoningai ir atsitiktinai žmonių išplatinta viso pasaulio vidutinio ir subtropinio klimato zonose. Šiuo metu randamas Pietų Afrikoje, Australijoje, Naujojoje Zelandijoje ir Šiaurės Amerikoje. Šis moliuskas tam tikruose regionuose plačiai naudojamas maistui ir dirbtinai veisiamas, tačiau taip pat daug kur laikomas sodų kenkėju, ypač regionuose, kur buvo išplatintas atsitiktinai ir kur nėra įprasta šias sraiges naudoti maistui.
Vidurio Europos mokslininkai dažniausiai priskiria Cornu genčiai (Born, 1778).[1] Italų autoriai priskiria moliuskus Cantareus genčiai (Risso, 1826).[2][3] Veisėjų taip pat Pietų Europos specialiojoje literatūroje dažnai vadinama Helix aspersa.[4][5]
Raibąją sraigenę geriausia aprašyti lyginant su vynuogine sraige. Lyginant abiejų rūšių suaugusius individus akivaizdu, kad raibosios sraigenės kiautas lieka mažesnis nei vynuoginės sraigės. Raibosios sraigenės kiauto aukštis siekia 4 cm, tuo tarpu kai vynuoginės sraigės vidutiniškai 5 cm, o kartais ir 6 cm.
Kaip ir daugelis sraigių, yra hermafroditė, turi ir patino ir patelės lytinę sistemą. Pieno spalvos kiaušiniai vystosi dirvoje.
Kilusi iš Europos ir vėliau paplitusi daugelyje šalių.
Raiboji sraigenė yra pavojingas kenkėjas, naktimis ar po didelio lietaus nusiaubiantis soduose augančius minkštastiebius augalus. Sausu oru ji lindi savo kriauklėje angą užlipdžiusi išdžiūvusiomis gleivėmis.
Raiboji sraigenė (kiti pavadinimai – aptaškytoji sraigė, margoji didsraigė) (Cornu aspersum, Helix aspersa, Cryptomphalus aspersus arba Cantareus aspersus) – pilvakojų (Gastropoda) klasės sausumos sraigė, priskiriama didsraigių šeimai. Tai vienas geriausiai žinomų sausumos moliuskų, nors Vidurio Europoje nėra tokia žinoma nei jos didžioji giminaitė vynuoginė sraigė. Raiboji sraigenė natūraliai paplitusi Viduržemio jūros regione ir vakarų Europoje, tačiau sąmoningai ir atsitiktinai žmonių išplatinta viso pasaulio vidutinio ir subtropinio klimato zonose. Šiuo metu randamas Pietų Afrikoje, Australijoje, Naujojoje Zelandijoje ir Šiaurės Amerikoje. Šis moliuskas tam tikruose regionuose plačiai naudojamas maistui ir dirbtinai veisiamas, tačiau taip pat daug kur laikomas sodų kenkėju, ypač regionuose, kur buvo išplatintas atsitiktinai ir kur nėra įprasta šias sraiges naudoti maistui.
Vidurio Europos mokslininkai dažniausiai priskiria Cornu genčiai (Born, 1778). Italų autoriai priskiria moliuskus Cantareus genčiai (Risso, 1826). Veisėjų taip pat Pietų Europos specialiojoje literatūroje dažnai vadinama Helix aspersa.
Helix aspersa, conhecida pelo nome comum caracoleta,[3] ou caracoleta-de-jardim, é a espécie de caracol terrestre mais comum e conhecida. É um molusco gastrópode pulmonado pertencente à família Helicidae.[4]
Helix aspersa, conhecida pelo nome comum caracoleta, ou caracoleta-de-jardim, é a espécie de caracol terrestre mais comum e conhecida. É um molusco gastrópode pulmonado pertencente à família Helicidae.
