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Sensory Organs Of Gastropods
The sensory organs of gastropods (snails and slugs) include olfactory organs, eyes, statocysts and mechanoreceptors. Gastropods have no sense of hearing.Chase R.: ''Sensory Organs and the Nervous System''. in Barker G. M. (ed.): ''The biology of terrestrial molluscs''. CABI Publishing, Oxon, UK, 2001, . 1–146, cited pages: 179–211. Olfactory organs In terrestrial gastropods the most important sensory organs are the olfactory organs which are located on the tips of the 4 tentacles. Some terrestrial gastropods can track the odor of food using their tentacles ( tropotaxis) and the wind ( anemotaxis). In opisthobranch marine gastropods, the chemosensory organs are two protruding structures on top of the head. These are known as rhinophores. An opisthobranch sea slug ''Navanax inermis'' has chemoreceptors on the sides of its mouth to track mucopolysaccharides in the slime trails of prey, and of potential mates. The freshwater snail '' Bithynia tentaculata'' is capabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sense
A sense is a biological system used by an organism for sensation, the process of gathering information about the world through the detection of Stimulus (physiology), stimuli. (For example, in the human body, the brain which is part of the central nervous system receives signals from the senses which continuously receive information from the environment, interprets these signals, and causes the body to respond, either chemically or physically.) Although traditionally five human senses were identified as such (namely Visual perception, sight, Olfaction, smell, Somatosensory system, touch, taste, and hearing), it is now recognized that there are many more. Senses used by non-human organisms are even greater in variety and number. During sensation, sense organs collect various stimuli (such as a sound or smell) for Transduction (physiology), transduction, meaning transformation into a form that can be understood by the brain. Sensation and perception are fundamental to nearly every ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navanax Inermis
''Navanax inermis'', common name the California aglaja, is a large species of predatory sea slug, a marine opisthobranch gastropod mollusk in the family Aglajidae. ''Navanax'' is not a nudibranch, even though it somewhat resembles one; it belongs to a more ancient lineage of opisthobranchs called the cephalaspideans or head shield slugs and snails. Description The body of ''N. inermis'' can be tan, black, or purple, with yellowish streaks. Yellow or orange streaks and blue dots are visible on the margins. It has two large parapodial folds that run the length of either side of the body, and almost touch at the midsection. This species possesses a small internal shell. Individuals are typically between 2.5 and 10 inches in length. ''Navanax inermis'' does not possess a radula or organs associated with vision. Distribution and habitat This species occurs in the eastern Pacific Ocean and Gulf of California. Its range is from Monterey, California to Baja California. ''Navanax ine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocelli
A simple eye (sometimes called a pigment pit) refers to a form of eye or an optical arrangement composed of a single lens and without an elaborate retina such as occurs in most vertebrates. In this sense "simple eye" is distinct from a multi-lensed "compound eye", and is not necessarily at all simple in the usual sense of the word. The structure of an animal's eye is determined by the environment in which it lives, and the behavioural tasks it must fulfill to survive. Arthropods differ widely in the habitats in which they live, as well as their visual requirements for finding food or conspecifics, and avoiding predators. Consequently, an enormous variety of eye types are found in arthropods. They possess a wide variety of novel solutions to overcome visual problems or limitations. Use of the term ''simple eye'' is flexible, and must be interpreted in proper context; for example, the eyes of humans and of other large animals such as most cephalopods, are ''camera eyes'' and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basommatophora
Basommatophora was a term that was previously used as a taxonomic informal group, a group of snails within the informal group Pulmonata, the air-breathing slugs and snails. According to the taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), whenever monophyly has not been tested, or where a traditional taxon of gastropods has now been discovered to be paraphyletic or polyphyletic, the term "group" or "informal group" was used. Basommatophora are known from the Carboniferous to the Recent periods.(in Czech) Pek I., Vašíček Z., Roček Z., Hajn. V. & Mikuláš R.: ''Základy zoopaleontologie''. - Olomouc, 1996. 264 pp., . Most of the families in this suborder are air-breathing freshwater snails. The three most abundant families in terms of number of species are, the Lymnaeidae (pond snails), the Planorbidae (ramshorn snails) and the Physidae (pouch or bubble snails). These are found in ponds, creeks, ditches, and shallow lakes nearly worldwide. The Siphonariidae on the ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylommatophora
Stylommatophora is an orderPhilippe Bouchet, Jean-Pierre Rocroi, Bernhard Hausdorf, Andrzej Kaim, Yasunori Kano, Alexander Nützel, Pavel Parkhaev, Michael Schrödl and Ellen E. Strong. 2017. Revised Classification, Nomenclator and Typification of Gastropod and Monoplacophoran Families'. Malacologia, 61(1-2): 1-526. of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This taxon includes most land snails and slugs. The two strong synapomorphies of Stylommatophora are a long pedal gland placed beneath a membrane and two pairs of retractile tentacles (Dayrat & Tillier). Several families in this group contain species of snails and slugs that create love darts. Stylommatophora are known from the Cretaceous period up to the present day. Pek I., Vašíček Z., Roček Z., Hajn. V. & Mikuláš R. (1996). ''Základy zoopaleontologie''. Olomouc, 264 pp., . 2005 taxonomy According to the taxonomy of the Gastropoda by Bouchet & Rocroi (2005) based on ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropod Eye
The sensory organs of gastropods (snails and slugs) include olfactory organs, eyes, statocysts and mechanoreceptors. Gastropods have no sense of hearing.Chase R.: ''Sensory Organs and the Nervous System''. in Barker G. M. (ed.): ''The biology of terrestrial molluscs''. CABI Publishing, Oxon, UK, 2001, . 1–146, cited pages: 179–211. Olfactory organs In terrestrial gastropods the most important sensory organs are the olfactory organs which are located on the tips of the 4 tentacles. Some terrestrial gastropods can track the odor of food using their tentacles ( tropotaxis) and the wind ( anemotaxis). In opisthobranch marine gastropods, the chemosensory organs are two protruding structures on top of the head. These are known as rhinophores. An opisthobranch sea slug ''Navanax inermis'' has chemoreceptors on the sides of its mouth to track mucopolysaccharides in the slime trails of prey, and of potential mates. The freshwater snail ''Bithynia tentaculata'' is capable of de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathymodiolus Childressi
''Bathymodiolus childressi'' is a species of deepwater mussel, a marine bivalve mollusk species in the family Mytilidae, the mussels. Although this species has been known since 1985,Childress J.J., Fisher C.R., Brooks J.M., Kennicutt M.C., II, Bidigare R. & Anderson A. (1986) A methanotrophic marine molluscan symbiosis: mussels fueled by gas. Science, 233, 1306-1308. it was formally described as a species in 1998. Habitat This species lives in cold seeps in the Gulf of Mexico. ''Bathymodiolus childressi'' is stenothermal species living in temperatures ranging from 6.5 to 7.2 °C.Berger M. S. & Young C. M. (2006). "Physiological response of the cold-seep mussel ''Bathymodiolus childressi'' to acutely elevated temperature". ''Marine Biology'' 149(6): 1397-1402. However it was able to survive the temperature of 20 °C in the laboratory. Symbiosis This mussel harbors intracellular methanotrophic bacteria in its gills. The bacteria provide carbon to the mussel. Inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathynerita Naticoidea
''Bathynerita naticoidea'' is a species of small sea snail, a marine gastropod mollusc in the family Neritidae, the nerites. This species is endemic to underwater cold seeps (oil seeps and gas seeps) in the northern Gulf of Mexico and in the Caribbean. The possible placement of this species within the closely allied family Phenacolepadidae has been under discussion. Species from these habitats can be collected by manned submersibles or by remotely operated underwater vehicles. Distribution This species lives in cold seeps in the northern Gulf of Mexico and in the accretionary wedge of Barbados in the Caribbean in the upper continental slope, in depths from 400 to 2100 m. Examples of localities include: * "Bush Hill" (27°46.9478 N; 91°30.5266 W) * methane seep "Brine Pool NR-1" in depth 650 m (27°43.415 N; 91°16.756 W) [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (gastropod)
The operculum (; ) is a corneous or calcareous anatomical structure like a trapdoor that exists in many (but not all) groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc. The operculum is attached to the upper surface of the foot and in its most complete state, it serves as a sort of "trapdoor" to close the aperture of the shell when the soft parts of the animal are retracted. The shape of the operculum varies greatly from one family of gastropods to another. It is fairly often circular, or more or less oval in shape. In species where the operculum fits snugly, its outline corresponds exactly to the shape of the aperture of the shell and it serves to seal the entrance of the shell. Many families have opercula that are reduced in size, and which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemoreception
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 dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leeches
Leeches are segmented parasitism, parasitic or Predation, predatory worms that comprise the Class (biology), subclass Hirudinea within the phylum Annelida. They are closely related to the Oligochaeta, oligochaetes, which include the earthworm, and like them have soft, muscular segmented bodies that can lengthen and contract. Both groups are hermaphrodites and have a clitellum, but leeches typically differ from the oligochaetes in having suckers at both ends and in having ring markings that do not correspond with their internal segmentation. The body is muscular and relatively solid, and the coelom, the spacious body cavity found in other annelids, is reduced to small channels. The majority of leeches live in freshwater habitats, while some species can be found in terrestrial or marine environments. The best-known species, such as the medicinal leech, ''Hirudo medicinalis'', are hematophagous, attaching themselves to a host with a sucker and feeding on blood, having first secr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bithynia Tentaculata
''Bithynia tentaculata'', common names the mud bithynia or common bithynia, or faucet snailKipp R. M. & Benson A. (2008). ''Bithynia tentaculata''. USGS Nonindigenous Aquatic Species Database, Gainesville, FL. https://nas.er.usgs.gov/queries/FactSheet.asp?speciesID=987 Revision Date: 2/28/2007. is a relatively small species of freshwater snail with gills and an operculum, an aquatic prosobranch gastropod mollusk in the family Bithyniidae. Taxonomy ''Bithynia tentaculata'' is the type species of the genus ''Bithynia''. Forms of ''Bithynia tentaculata'' include: * ''Bithynia tentaculata'' f. ''codia'' * ''Bithynia tentaculata'' f. ''excavata'' * ''Bithynia tentaculata'' f. ''gigas'' * ''Bithynia tentaculata'' f. ''producta'' Menke, 1828 * † ''Bithynia tentaculata tellinii'' Sacco, 1886 The variety † ''Bithynia tentaculata'' var. ''allobrogica'' Fontannes, 1881: synonym of † '' Bithynia minor'' Locard, 1878 Distribution Indigenous distribution The distribution of ''Bith ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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