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Bathyhedyle Boucheti
''Bathyhedyle boucheti'' is a species of panpulmonate slug, a deep-sea dwelling gastropod native to the continental slope off the coast of Mozambique. It is the first ever such panpulmonate slug to be discovered at such depths. It is the only known member of its family group. Its radular formula is 1.1.2. Physical description Adults have a body length of approximately 9 mm. The animal's head includes two pairs of tentacles, one set of labial tentacles and another set of rhinophores, both sets of which are cylindrical, solid, and taper at their tips. The eyes are located just behind the rhinophores. The animal's creeping foot is three times the width of its head and tapers to a point at the posterior of the animal. The anterior end of the foot also has a pair of propodial tentacles. The animal's head is brown, and the tentacles and foot are semi-translucent. A distinct black stripe extends from the dorsal part of the cephalic tentacles and proceeds to the end of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animalia
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notum
The notum (plural nota) is the dorsal portion of an insect's thoracic segment, or the dorsal surface of the body of nudibranch gastropods. The word "notum" is always applied to dorsal structures; in other words structures that are part of the back of an animal, as opposed to being part of the animal's ventral surface, or underside. This word is used in entomology, the study of insects, and in malacology, the study of mollusks. In malacology the word is used to describe the back of the body of the taxonomic group of marine, shell-less gastropods that are known as nudibranchs. In insects In entomology, the notum is the dorsal portion of an insect's thoracic segment. The pterothoracic nota (comprising the meso- and metathoracic segments) have two main divisions - the anterior wing-bearing alinotum and the posterior phragma-bearing postnotom.Cranston, P. S, and P. J Gullan. The Insects: An Outline Of Entomology. 5th ed. Chichester: Wiley-Blackwell, 2014. Print. The phragma, or endoterg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limnic
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include non- salty mineral-rich waters such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/ sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Fresh water is the water resource that is of the most and immediate use to humans. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of higher plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive. Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampulla
An ampulla (; ) was, in Ancient Rome, a small round vessel, usually made of glass and with two handles, used for sacred purposes. The word is used of these in archaeology, and of later flasks, often handle-less and much flatter, for holy water or holy oil in the Middle Ages, often bought as souvenirs of pilgrimages, such as the metal Monza ampullae of the 6th century. Materials include glass, ceramics and metal. Unguentarium is a term for a bottle believed to have been used to store perfume, and there is considerable overlap between the two terms, one defined by shape and the other by purpose. The glass Holy Ampulla was part of the French coronation regalia and believed to have divine origins. Similar, but far more recent, is the Ampulla in the British regalia, a hollow, gold, eagle-shaped vessel from which the anointing oil is poured by the Archbishop of Canterbury at the anointing of a new British sovereign at their coronation A coronation is the act of placement or bes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovotestis
An ovotestis is a gonad with both testicular and ovarian aspects. In humans, ovotestes are an infrequent anatomical variation associated with gonadal dysgenesis. The only mammals where ovotestes are not symptomatic of an intersex variation are moles, wherein females possess ovotestes along with a masculinized clitoris. These ovotestes in nonpregnant female moles secrete eight times as much testosterone as the ovotestes of pregnant moles. In invertebrates that are normally hermaphroditic, such as most gastropods (snails and slugs) in the clade Eupulmonata, an ovotestis is a common feature of the reproductive anatomy. In mice, ovotestes are structured such that the central region is testicular tissue while the poles both contain ovarian tissue. Experiments involving the SOX9 gene, which is initiated by the SRY region of the Y chromosome, have shown the gene’s requirement for testicular differentiation from the presence of ovotestis formation within XX Sox9 trangenic mice. (6) Ovo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphroditic
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many taxonomic groups of animals (mostly invertebrates) do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. For example, the great majority of tunicates, pulmonate molluscs, opisthobranch, earthworms, and slugs are hermaphrodites. Hermaphroditism is also found in some fish species and to a lesser degree in other vertebrates. Most plants are also hermaphrodites. Animal species having different sexes, male and female, are called gonochoric, which is the opposite of hermaphrodite. There are also species where hermaphrodites exist alongside males (called androdioecy) or alongside females (called gynodioecy), or all three exist in the same species (called trioecy); these three systems are so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statocyst
The statocyst is a balance sensory receptor present in some aquatic invertebrates, including bivalves, cnidarians, ctenophorans, echinoderms, cephalopods, and crustaceans. A similar structure is also found in ''Xenoturbella''. The statocyst consists of a sac-like structure containing a mineralised mass (statolith) and numerous innervated sensory hairs (setae). The statolith's inertia causes it to push against the setae when the animal accelerates. Deflection of setae by the statolith in response to gravity activates neurons, providing feedback to the animal on change in orientation and allowing balance to be maintained. In other words, the statolith shifts as the animal moves. Any movement large enough to throw the organism off balance causes the statolith to brush against tiny bristles which in turn send a message to the brain to correct its balance. It may have been present in the common ancestor of cnidarians and bilaterians. Hearing In cephalopods like squids, statocysts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve Ring
A circumesophageal or circumpharyngeal nerve ring is an arrangement of nerve ganglia around the esophagus/ pharynx of an animal. It is a common feature of nematodes, molluscs, and many other invertebrate animals, though it is absent in all vertebrate animals and is not structurally possible in simpler ones such as water bears. The nerve ring, also called a nerve collar, creates a complete and closed loop around the food-entry parts of the animal's anatomy. In a typical molluscan arrangement, these include the cerebral, pedal, and pleural ganglia, with the esophagus passing through the center of the ring. In nematodes, the ring consists of only two to four large associative cells connected to two paired lateral ganglia, two ventral ganglia, and a single unpaired dorsal ganglion. Among arthropods, the usual arrangement is a single ganglion (the cerebral) positioned above the esophagus, a single ganglion or nerve mass (the subesophageal) below it, and commissures connecting the two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its structure varies across species. The pharynx carries food and air to the esophagus and larynx respectively. The flap of cartilage called the epiglottis stops food from entering the larynx. In humans, the pharynx is part of the digestive system and the conducting zone of the respiratory system. (The conducting zone—which also includes the nostrils of the nose, the larynx, trachea, bronchi, and bronchioles—filters, warms and moistens air and conducts it into the lungs). The human pharynx is conventionally divided into three sections: the nasopharynx, oropharynx, and laryngopharynx. It is also important in vocalization. In humans, two sets of pharyngeal muscles form the pharynx and determine the shape of its lumen. They are arranged as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euthyneury
Euthyneury is a plesiomorphic condition present in some gastropods which is a result of two evolutionary events. The first event, which was experienced by the ancestors of all extant gastropods, is known as torsion. Torsion describes the event in which the intestines, heart, nephridia, gills, and nerve cords "twisted" causing some organs to migrate from the animal's left to its right in order to accommodate the relocation of the mantle cavity close to the animal's head. Torsion created a condition in the cerebrovisceral commissures called streptoneury. Secondarily, some gastropod lineages ''detorted'': they reversed the torsion event and straightened out their internal organs, uncrossing the commissures in the process. It is this second state, one in which the commissures have once again become untwisted, that is called ''euthyneury''. The Opisthobranchia Opisthobranchs () is now an informal name for a large and diverse group of specialized complex gastropods which used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
