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Pontohedyle
''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 rou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microhedylacea
Acochlidiacea, common name acochlidians, are a taxonomic clade of very unusual sea snails and sea and freshwater slugs, aquatic gastropod mollusks within the large clade Heterobranchia. Acochlidia is a variant spelling. Description These are mostly very small animals, without a shell or gills, distinguished by the visceral mass being sharply set off from the rest of the body. Being a small group with only 30 species worldwide known in 2010, and 32 species described in 2011, and 33 in 2012 (+9 undescribed ''Pontohedyle'' species), these slugs are morphologically and biologically highly aberrant and diverse, comprising a series of unusual characters (e.g. secondary gonochorism, lack of copulatory organs, asymmetric radulae). Most acochlidians live interstitially in marine sands, while some have conquered limnic systems (uniquely within opisthobranch gastropods). Taxonomy Nils Hjalmar Odhner established this taxon as a family in 1937, when he created the families Microhedylid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acochlidiacea
Acochlidiacea, common name acochlidians, are a taxonomic clade of very unusual sea snails and sea and freshwater slugs, aquatic gastropod mollusks within the large clade Heterobranchia. Acochlidia is a variant spelling. Description These are mostly very small animals, without a shell or gills, distinguished by the visceral mass being sharply set off from the rest of the body. Being a small group with only 30 species worldwide known in 2010, and 32 species described in 2011, and 33 in 2012 (+9 undescribed ''Pontohedyle'' species), these slugs are morphologically and biologically highly aberrant and diverse, comprising a series of unusual characters (e.g. secondary gonochorism, lack of copulatory organs, asymmetric radulae). Most acochlidians live interstitially in marine sands, while some have conquered limnic systems (uniquely within opisthobranch gastropods). Taxonomy Nils Hjalmar Odhner established this taxon as a family in 1937, when he created the families Microhedylid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acochlidian
Acochlidiacea, common name acochlidians, are a taxonomic clade of very unusual sea snails and sea and freshwater slugs, aquatic gastropod mollusks within the large clade Heterobranchia. Acochlidia is a variant spelling. Description These are mostly very small animals, without a shell or gills, distinguished by the visceral mass being sharply set off from the rest of the body. Being a small group with only 30 species worldwide known in 2010, and 32 species described in 2011, and 33 in 2012 (+9 undescribed ''Pontohedyle'' species), these slugs are morphologically and biologically highly aberrant and diverse, comprising a series of unusual characters (e.g. secondary gonochorism, lack of copulatory organs, asymmetric radulae). Most acochlidians live interstitially in marine sands, while some have conquered limnic systems (uniquely within opisthobranch gastropods). Taxonomy Nils Hjalmar Odhner established this taxon as a family in 1937, when he created the families Microhedylid ... [...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] |
Microhedylidae
Parhedylidae are a taxonomic family of sea slugs, marine gastropod mollusks in the superfamily Parhedyloidea. MolluscaBase eds. (2021). MolluscaBase. Parhedylidae Thiele, 1931. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=411947 on 2021-06-17 2005 taxonomy Microhedylidae has been listed as a synonym of Parhedylidae in the taxonomy of Bouchet & Rocroi (2005). Ganitidae Rankin, 1979 has been listed as a sole family within Hedylopsoidea. The type genus of Livorniellidae was ''Livorniella'' Rankin, 1979. 2010 taxonomy Sensu Schrödl & Neusser (2010)Schrödl M. & Neusser T. P. (2010). "Towards a phylogeny and evolution of Acochlidia (Mollusca: Gastropoda: Opisthobranchia)". ''Zoological Journal of the Linnean Society'' 158: 124–154. . is Microhedylidae within the clade Microhedylacea. Parhedylidae is a synonym of Microhedylidae. Microhedylidae s.l. may informally include Ganitidae, but inclusion of Ganitidae within ... [...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] |
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] |
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] |
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] |
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] |
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] |
