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Paramysis Baeri
''Paramysis baeri'' is a species of mysid crustacean from the genus ''Paramysis'', named in honour of the prominent biologist Karl Ernst von Baer. Its body is long, and it is only found in the coastal waters of the Caspian Sea, on sandy and muddy bottoms, at depths of less than . For over a century, it was thought to be distributed throughout the whole Ponto-Caspian basin, but recently the range was reconsidered after the rediscovery and re-establishment of the closely related species ''Paramysis bakuensis''. Since the taxonomical status of ''P. baeri'' has been reconsidered, the distribution and ecology of the species remains poorly known. ''Paramysis baeri'' can be distinguished from ''P. bakuensis'' and other species of the subgenus ''Paramysis'' s. str. by the rather broad, almost quadrangular exopod of maxilla 2, the strongly serrated paradactylar claw-setae of pereiopod The decapod (crustaceans such as a crab, lobster, shrimp or prawn) is made up of 20 body segments g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, 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 Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caspian Sea
The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia, south of the fertile plains of Southern Russia in Eastern Europe, and north of the mountainous Iranian Plateau of Western Asia. It covers a surface area of (excluding the highly saline lagoon of Garabogazköl to its east) and a volume of . It has a salinity of approximately 1.2% (12 g/L), about a third of the salinity of average seawater. It is bounded by Kazakhstan to the northeast, Russia to the northwest, Azerbaijan to the southwest, Iran to the south, and Turkmenistan to the southeast. The sea stretches nearly from north to south, with an average width of . Its gross coverage is and the surface is about below sea level. Its main freshwater inflow, Europe's longest river, the Volga, enters at the shallow north end. Two deep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustaceans Described In 1882
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pereiopod
The decapod (crustaceans such as a crab, lobster, shrimp or prawn) is made up of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various groups these may be reduced or missing. They are, from head to tail: Cephalothorax Head # antennules # antennae #mandibles # first maxillae # second maxillae The head also bears the (usually stalked) compound eyes. The distal portion of a mandible or maxilla which has a sensory function is known as a palp. Thorax / pereon #first maxillipeds #second maxillipeds #third maxillipeds #first pereiopods #second pereiopods #third pereiopods #fourth pereiopods #fifth pereiopods Maxillipeds are appendages modified to function as mouthparts. Particularly in the less advanced decapods, these can be very similar to the pereiopods. Pereiopods are primarily walking legs and are also used for gathering food. They are also the ten legs from which decapods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod Maxilla
In arthropods, the maxillae (singular maxilla) are paired structures present on the head as mouthparts in members of the clade Mandibulata, used for tasting and manipulating food. Embryologically, the maxillae are derived from the 4th and 5th segment of the head and the maxillary palps; segmented appendages extending from the base of the maxilla represent the former leg of those respective segments. In most cases, two pairs of maxillae are present and in different arthropod groups the two pairs of maxillae have been variously modified. In crustaceans, the first pair are called maxillulae (singular maxillula). Modified coxae at the base of the pedipalps in spiders are also called "maxillae", although they are not homologous with mandibulate maxillae. Myriapoda Millipedes In millipedes, the second maxillae have been lost, reducing the mouthparts to only the first maxillae which have fused together to form a gnathochilarium, acting as a lower lip to the buccal cavity and the man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portable Document Format
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems.Adobe Systems IncorporatedPDF Reference, Sixth edition, version 1.23 (53 MB) Nov 2006, p. 33. Archiv/ref> Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991. PDF was standardized as ISO 32000 in 2008. The last edition as ISO 32000-2:2020 was published in December 2020. PDF files may contain a variety of content besides flat text and graphics including logical structuring elements, interactive elements such as annotations and form-fields, layers, rich media (including video con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zootaxa
''Zootaxa'' is a peer-reviewed scientific mega journal for animal taxonomists. It is published by Magnolia Press (Auckland, New Zealand). The journal was established by Zhi-Qiang Zhang in 2001 and new issues are published multiple times a week. From 2001 to 2020, more than 60,000 new species have been described in the journal accounting for around 25% of all new taxa indexed in The Zoological Record in the last few years. Print and online versions are available. Temporary suspension from JCR The journal exhibited high levels of self-citation and its journal impact factor of 2019 was suspended from ''Journal Citation Reports'' in 2020, a sanction which hit 34 journals in total. Biologist Ross Mounce noted that high levels of self-citation may be inevitable for a journal which publishes a large share of new species classification. Later that year this decision was reversed and it was admitted that levels of self-citation are appropriate considering the large proportion of papers f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paramysis Bakuensis
''Paramysis bakuensis'' is a species of mysid crustacean from the family Mysidae, named by the locality from where it was originally described, the town of Baku in Azerbaijan by the Caspian Sea. Taxonomic history After the description by Norwegian carcinologist Georg Ossian Sars, the species was mentioned only twice among the mysids of the Sea of Azov basin, but soon synonymized with '' Paramysis baeri''. In 60 years it was rediscovered while combined morphological and molecular revision of ''P. baeri'', restored and redescribed. Distribution The species is distributed throughout brackish and fresh waters of the Ponto-Caspian basin. It is found in the Caspian Sea, the Sea of Azov, rivers Volga, Don, Kuban and Danube; in the rivers up to over 500 km upstream. All the previous mentionings of ''P. baeri'' outside the Caspian Sea should probably be attributed to ''P. bakuensis''. The ranges of ''P. bakuensis'' and ''P. baeri'' partly overlap: they can be found together in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paratethys
The Paratethys sea, Paratethys ocean, Paratethys realm or just Paratethys was a large shallow inland sea that stretched from the region north of the Alps over Central Europe to the Aral Sea in Central Asia. Paratethys was peculiar due to its paleogeography: it consisted of a series of deep basins, formed during the Oxfordian stage of the Late Jurassic as an extension of the rift that formed the Central Atlantic Ocean. These basins were connected with each other and the global ocean by narrow and shallow seaways that often limited water exchange and caused widespread long-term anoxia. Paratethys was at times reconnected with the Tethys or its successors (the Mediterranean Sea or the Indian Ocean) during the Oligocene and the early and middle Miocene times, but at the onset of the late Miocene epoch, the tectonically trapped sea turned into a megalake from the eastern Alps to what is now Kazakhstan. From the Pliocene epoch onward (after 5 million years ago), Paratethys be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Ernst Von Baer
Karl Ernst Ritter von Baer Edler von Huthorn ( – ) was a Baltic German scientist and explorer. Baer was a naturalist, biologist, geologist, meteorologist, geographer, and is considered a, or the, founding father of embryology. He was a member of the Russian Academy of Sciences, a co-founder of the Russian Geographical Society, and the first president of the Russian Entomological Society, making him one of the most distinguished Baltic German scientists. Life Karl Ernst von Baer was born into the Baltic German noble Baer family ( et) in the Piep Manor ( et), Jerwen County, Governorate of Estonia (in present-day Lääne-Viru County, Estonia), as a knight by birthright. His patrilineal ancestors were of Westphalian origin and originated in Osnabrück. He spent his early childhood at Lasila manor, Estonia. He was educated at the Knight and Cathedral School in Reval (Tallinn) and the Imperial University of Dorpat (Tartu). In 1812, during his tenure at the uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arthropod cuticle, cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an exoskeleton, external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior Organ (anatomy), organs; it has an open circulatory system. Like their exteriors, the internal or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
