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Pontohedyle Verrucosa Radula
''Pontohedyle'' is a genus of sea slugs, acochlidians, shell-less marine gastropod mollusks in the family Microhedylidae. Sea slugs in this genus are highly simplified and uniform. Distribution The genus ''Pontohedyle'' shows a circumtropical distribution with a single derived species (Mediterranean/ Black Sea ''Pontohedyle milaschewitchii'') inhabiting temperate waters. In the absence of a fossil record for meiofaunal slugs, the only available estimate for divergence times derives from a molecular clock approach, calibrated with shelled heterobranch fossils. Jörger et al. (2010)Jörger K. M., Stöger I., Kano Y., Fukuda H., Knebelsberger T. & Schrödl M. (2010). "On the origin of Acochlidia and other enigmatic euthyneuran gastropods, with implications for the systematics of Heterobranchia". ''BMC Evolutionary Biology'' 10: 323. . estimated the origin of the genus ''Pontohedyle'' to the late Cretaceous, 84 mya (95% confidence interval ranging from 160–60 mya), providing a rough ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digestive Gland
The hepatopancreas, digestive gland or midgut gland is an organ of the digestive tract of arthropods and molluscs. It provides the functions which in mammals are provided separately by the liver and pancreas, including the production of digestive enzymes, and absorption of digested food. Arthropods Arthropods, especially detritivores in the Order Isopoda, Suborder Oniscidea (woodlice), have been shown to be able to store heavy metals in their hepatopancreas. This could lead to bioaccumulation through the food chain and implications for food web destruction, if the accumulation gets high enough in polluted areas; for example, high metal concentrations are seen in spiders of the genus ''Dysdera'' which feed on woodlice, including their hepatopancreas, the major metal storage organ of isopods in polluted sites. Molluscs The hepatopancreas is a centre for lipid metabolism and for storage of lipids in gastropods.Böer M., Graeve M. & Kattner G. (2006). "Exceptional long-term starvat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperate Water
In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout the year and more distinct seasonal changes compared to tropical climates, where such variations are often small and usually only have precipitation changes. In temperate climates, not only do latitudinal positions influence temperature changes, but sea currents, prevailing wind direction, continentality (how large a landmass is) and altitude also shape temperate climates. The Köppen climate classification defines a climate as "temperate" C, when the mean temperature is above but below in the coldest month to account for the persistency of frost. However, other climate classifications set the minimum at . Zones and climates The north temperate zone extends from the Tropic of Cancer (approximately 23.5° north latitude) to the Arctic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pontohedyle Verrucosa
''Pontohedyle verrucosa'' is a species of sea slug, an acochlidian, a shell-less marine gastropod mollusc in the family Microhedylidae.Jörger K. M., Norenburg J. L., Wilson N. G. & Schrödl M. (2012). "Barcoding against a paradox? Combined molecular species delineations reveal multiple cryptic lineages in elusive meiofaunal sea slugs". ''BMC Evolutionary Biology ''BMC Ecology and Evolution'' (since January 2021), previously ''BMC Evolutionary Biology'' (2001–2020), is a peer-reviewed open access scientific journal covering all fields of evolutionary biology, including phylogenetics and palaeontology. It ...'' 12: 245. . References External links * Microhedylidae Gastropods described in 1970 {{Heterobranchia-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pontohedyle Milaschewitchii
''Pontohedyle milaschewitchii'' is a species of sea slug, an acochlidian, a shell-less marine gastropod mollusk in the family Microhedylidae.Jörger K. M., Norenburg J. L., Wilson N. G. & Schrödl M. (2012). "Barcoding against a paradox? Combined molecular species delineations reveal multiple cryptic lineages in elusive meiofaunal sea slugs". ''BMC Evolutionary Biology'' 12: 245. . Ecology The life cycle of all Acochlidiacea is not well known. ''Pontohedyle milaschewitchii'' lays a maximum of 40 eggs. References External links * Jörger K. M., Neusser T. P. & Schrödl M. (2007). "Re-description of a female ''Pontohedyle brasilensis'' (Rankin, 1979), a junior synonym of the Mediterranean ''P. milaschewitchii'' (Kowalevsky, 1901) (Acochlidia, Gastropoda)". ''Bonner Zoologische Beiträge'' 55(3/4): 283-290PDF * Jörger K. M., Neusser T. P., Haszprunar G. & Schrödl M. (2008). "Undersized and underestimated: 3D-visualization of the Mediterranean interstitial acochlidian gastro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radula
The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus. The radula is unique to the molluscs, and is found in every class of mollusc except the bivalves, which instead use cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs. The arrangement of teeth ( denticles) on the radular ribbon varies considerably from one group to another. In most of the more ancient lineages of gastropods, the radula is used to graze, by scraping diatoms and other microscopic algae off rock surfaces and other substrates. Predatory marine snails such as the Naticidae use the radula plus an acidic secretion to bore through the shell of other molluscs. Other predatory marine snails ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tentacle
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work mainly like muscular hydrostats. Most forms of tentacles are used for grasping and feeding. Many are sensory organs, variously receptive to touch, vision, or to the smell or taste of particular foods or threats. Examples of such tentacles are the eyestalks of various kinds of snails. Some kinds of tentacles have both sensory and manipulatory functions. A tentacle is similar to a cirrus, but a cirrus is an organ that usually lacks the tentacle's strength, size, flexibility, or sensitivity. A nautilus has cirri, but a squid has tentacles. Invertebrates Molluscs Many molluscs have tentacles of one form or another. The most familiar are those of the pulmonate land snails, which usually have two sets of tentacles on the head: when extended ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhinophores
A rhinophore is one of a pair of chemosensory club-shaped, rod-shaped or ear-like structures which are the most prominent part of the external head anatomy in sea slugs, marine gastropod opisthobranch mollusks such as the nudibranchs, sea hares (Aplysiomorpha), and sap-sucking sea slugs (Sacoglossa). Etymology The name relates to the rhinophore's function as an organ of "smell". ''Rhino-'' means nose from Ancient Greek ῥίς ''rhis'' and from its genitive ῥινός ''rhinos''. "Phore" means "to bear" from New Latin ''-phorus'' and from Greek -phoros (φορος) "bearing", a derivative of ''phérein'' (φέρειν). Function Rhinophores are scent or taste receptors, also known as chemosensory organs situated on the dorsal surface of the head. They are primarily used for distance chemoreception and rheoreception (response to water current). The "scents" detected by rhinophores are chemicals dissolved in the sea water. The fine structure and hairs of the rhinophore ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermiform
Vermiform (ˈvərməˌfôrm) describes something shaped like a worm. The expression is often employed in biology and anatomy to describe usually soft body parts or animals that are more or less tubular or cylindrical. The word root is Latin, ''vermes'' (worms) and ''formes'' (shaped). A well known example is the vermiform appendix, a small, blind section of the gut in humans and a number of other mammals. A number of soft-bodied animal phyla are typically described as vermiform. The better-known ones are undoubtedly the annelids (earthworm and relatives) and the roundworms (a very common, mainly parasitic group), but a number of less-well-known phyla answer to the same description. Examples range from the minute parasitic mesozoans to the larger-bodied free-living phyla like ribbon worms, peanut worms, and priapulids Priapulida (priapulid worms, from Gr. πριάπος, ''priāpos'' ' Priapus' + Lat. ''-ul-'', diminutive), sometimes referred to as penis worms, is a phylum o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tethys Ocean
The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean that covered most of the Earth during much of the Mesozoic Era and early Cenozoic Era, located between the ancient continents of Gondwana and Laurasia, before the opening of the Indian and Atlantic oceans during the Cretaceous Period. It was preceded by the Paleo-Tethys Ocean, which lasted between the Cambrian and the Early Triassic, while the Neotethys formed during the Late Triassic and lasted until the early Eocene (about 50 million years ago) when it completely closed. A portion known as the Paratethys formed during the Late Jurassic, was isolated during the Oligocene (34 million years ago) and lasted up to the Pliocene (about 5 million years ago), when it largely dried out. Many major seas and lakes of Europe and Western Asia, including the Mediterranean Sea, the Black Sea, the Caspian Sea, and the Aral Sea are thought to be remnants of the Paratethys. Ety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
