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Mating Of Gastropods
The mating of gastropods is a vast and varied topic, because the taxonomic class Gastropoda is very large and diverse, a group comprising sea snails and sea slugs, freshwater snails and land snails and slugs. Gastropods are second only to the class Insecta in terms of total number of species. Some gastropods have separate sexes, others are hermaphroditic. Some hermaphroditic groups have simultaneous hermaphroditism, whereas some sequential hermaphroditism. In addition, numerous very different mating strategies are used within different taxa. This article currently focuses primarily on the mating habits of air-breathing terrestrial slugs. Land slugs can be thought of as land snails that over evolutionary time have either lost the shell completely, have a very reduced external shell, or have retained only internal remnants of a shell. Land slugs are a highly polyphyletic group, which means that many land slug families are not at all closely related to one another. The majority of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snails Mating
A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastropoda that have a coiled shell that is large enough for the animal to retract completely into. When the word "snail" is used in this most general sense, it includes not just land snails but also numerous species of sea snails and freshwater snails. Gastropods that naturally lack a shell, or have only an internal shell, are mostly called ''slugs'', and land snails that have only a very small shell (that they cannot retract into) are often called ''semi-slugs''. Snails have considerable human relevance, including as food items, as pests, and as vectors of disease, and their shells are used as decorative objects and are incorporated into jewelry. The snail has also had some cultural significance, tending to be associated with lethargy. The snai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monophyly
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic groups are typically characterised by shared derived characteristics ( synapomorphies), which distinguish organisms in the clade from other organisms. An equivalent term is holophyly. The word "mono-phyly" means "one-tribe" in Greek. Monophyly is contrasted with paraphyly and polyphyly as shown in the second diagram. A ''paraphyletic group'' consists of all of the descendants of a common ancestor minus one or more monophyletic groups. A '' polyphyletic group'' is characterized by convergent features or habits of scientific interest (for example, night-active primates, fruit trees, aquatic insects). The features by which a polyphyletic group is differentiated from others are not inherited from a common ancestor. These definitions have taken ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deroceras Panormitanum
''Deroceras panormitanum'' is a species of air-breathing land slug, a terrestrial pulmonate gastropod mollusc in the family Agriolimacidae. This article is about ''Deroceras panormitanum'' ''sensu stricto'', which occurs predominantly only on Sicily and Malta. Previous to 2011, this name was also applied to what turned out to be a distinct species, '' Deroceras invadens'', a species which has spread around the world and is often a pest. Because this is a recent change in the taxonomy, for information on the species commonly referred to in the literature before 2011 as ''Deroceras panormitanum'', please see '' Deroceras invadens''. This species is not listed in the IUCN red list. Synonymy ''Deroceras panormitanum'' was described from Palermo in Sicily. It is now widely accepted that ''Deroceras pollonerae'' also described from Palermo, ''Deroceras caruanae'' described from Valletta on Malta, and ''Deroceras dubium'' from Malta are the same species. Recently Reise et al. (2011) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pheromone
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavior of the receiving individuals. There are ''alarm signal, alarm pheromones'', ''food trail pheromones'', ''sex pheromones'', and many others that affect behavior or physiology. Pheromones are used by many organisms, from basic unicellular prokaryotes to complex multicellular eukaryotes. Their use among insects has been particularly well documented. In addition, some vertebrates, plants and ciliates communicate by using pheromones. The ecological functions and evolution of pheromones are a major topic of research in the field of chemical ecology. Background The portmanteau word "pheromone" was coined by Peter Karlson and Martin Lüscher in 1959, based on the Greek φερω ''pheroo'' ('I carry') and ὁρμων ''hormon'' ('stimulating'). P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Somatosensory System
In physiology, the somatosensory system is the network of neural structures in the brain and body that produce the perception of touch (haptic perception), as well as temperature (thermoception), body position (proprioception), and pain. It is a subset of the sensory nervous system, which also represents visual, auditory, olfactory, and gustatory stimuli. Somatosensation begins when mechano- and thermosensitive structures in the skin or internal organs sense physical stimuli such as pressure on the skin (see mechanotransduction, nociception). Activation of these structures, or receptors, leads to activation of peripheral sensory neurons that convey signals to the spinal cord as patterns of action potentials. Sensory information is then processed locally in the spinal cord to drive reflexes, and is also conveyed to the brain for conscious perception of touch and proprioception. Note, somatosensory information from the face and head enters the brain through periphera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olfaction
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it occurs when an odor binds to a receptor within the nasal cavity, transmitting a signal through the olfactory system. Glomeruli aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain responsible for smell identification, memory, and emotion. There are many different causes for alteration, lack, or disturbance to a normal sense of smell, and can include damage to the nose or smell receptors, or central problems affecting the brain. Some causes include upper respiratory infections, traumatic brain injury, and neurodegenerative disease. History of study Early scientific study of the sense of smell includes the extensive doctoral dissertation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemoreceptor
A chemoreceptor, also known as chemosensor, is a specialized sensory receptor which transduces a chemical substance (endogenous or induced) to generate a biological signal. This signal may be in the form of an action potential, if the chemoreceptor is a neuron, or in the form of a neurotransmitter that can activate a nerve fiber if the chemoreceptor is a specialized cell, such as taste receptors, or an internal peripheral chemoreceptor, such as the carotid bodies. In physiology, a chemoreceptor detects changes in the normal environment, such as an increase in blood levels of carbon dioxide (hypercapnia) or a decrease in blood levels of oxygen (hypoxia), and transmits that information to the central nervous system which engages body responses to restore homeostasis. In bacteria, chemoreceptors are essential in the mediation of chemotaxis. Cellular chemoreceptors In prokaryotes Bacteria utilize complex long helical proteins as chemoreceptors, permitting signals to travel long di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deroceras Panormitanum 004
''Deroceras'' is a taxonomic genus of small to medium sized air-breathing land slugs in the family Agriolimacidae. Description Most species reach only 30–35 mm in length (max 45 mm). Coloration varies considerably within and between species but common patterns are pale cream, with or without darker flecks (never stripes), and a more uniform light gray or brown to black-brown. Mucus is usually colourless but in some species includes a white deposit when the slug has been disturbed. No keel continues from the tail along the back. The mantle is large (up to half the body length), containing a shell plate internally. The pneumostome lies in the posterior half of the mantle. Generally external appearance does not reliably distinguish one species from certain others, so species identification requires dissection to reveal the genitalia, unless the local species diversity is known to be low. The taxonomy, anatomy and other aspects of the biology of this genus were r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opisthobranchia
Opisthobranchs () is now an informal name for a large and diverse group of specialized complex gastropods which used to be united in the subclass Opisthobranchia. That taxon is no longer considered to represent a monophyletic grouping. Euopisthobranchia is a taxon containing a revised collection of opisthobranchs, and that taxon is considered monophyletic. Euopisthobranchia does not include some "traditional" opisthobranchs such as the Sacoglossa and the Acochlidiacea. The subclass Heterobranchia now contains all the species which used to be assigned to Opisthobranchia, plus all the species in the Pulmonata. The subclass Opisthobranchia included species in the order Cephalaspidea (bubble shells and headshield slugs), the sacoglossans, anaspidean sea hares, pelagic sea angels, sea butterflies, and many families of the Nudibranchia. ''Opisthobranch'' means "gills behind" (and to the right) of the heart. In contrast, ''Prosobranch'' means ''gills in front'' (of the heart). Opist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonata
Pulmonata or pulmonates, is an informal group (previously an order, and before that a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includes many land and freshwater families, and several marine families. The taxon Pulmonata as traditionally defined was found to be polyphyletic in a molecular study per Jörger ''et al.'', dating from 2010. Pulmonata are known from the Carboniferous Period to the present. Pulmonates have a single atrium and kidney, and a concentrated, symmetrical, nervous system. The mantle cavity is located on the right side of the body, and lacks gills, instead being converted into a vascularised lung. Most species have a shell, but no operculum, although the group does also include several shell-less slugs. Pulmonates are hermaphroditic, and some groups possess love darts. Linnean taxonomy The taxonomy of this group according to the taxonomy of the Ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banana Slug
Banana slugs are North American terrestrial slugs comprising the genus ''Ariolimax''. MolluscaBase eds. (2021). MolluscaBase. Ariolimax Mörch, 1859. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=995725 on 2021-08-25 They are often bright yellow (giving rise to the "banana" common name) although they may also be greenish, brown, tan, or white. Species Species within the genus ''Ariolimax'' include: ;Species brought into synonymy: * ''Ariolimax andersonii'' J. G. Cooper, 1872: synonym of Prophysaon andersonii (J.G. Cooper, 1872) (unaccepted combination) * ''Ariolimax californicus'' J.G. Cooper, 1872: synonym of ''Ariolimax californicus californicus'' J.G. Cooper, 1872 * ''Ariolimax californicus costaricensis'' Cockerell, 1890: synonym of '' Deroceras costaricensis'' (Cockerell, 1890) * ''Ariolimax hemphilli'' W. G. Binney, 1875: synonym of '' Hesperarion hemphilli'' (W.G. Binney, 1875) * ''Ariolimax niger'' J. G. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deroceras
''Deroceras'' is a Taxonomy (biology), taxonomic genus of small to medium sized air-breathing land slugs in the family Agriolimacidae. Description Most species reach only 30–35 mm in length (max 45 mm). Coloration varies considerably within and between species but common patterns are pale cream, with or without darker flecks (never stripes), and a more uniform light gray or brown to black-brown. Mucus is usually colourless but in some species includes a white deposit when the slug has been disturbed. No keel (slug), keel continues from the tail along the back. The Mantle (mollusc), mantle is large (up to half the body length), containing a shell plate internally. The pneumostome lies in the posterior half of the mantle. Generally external appearance does not reliably distinguish one species from certain others, so species identification requires dissection to reveal the genitalia, unless the local species diversity is known to be low. The taxonomy, anatomy and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
