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Microconchida
The order Microconchida is a group of small, spirally-coiled, encrusting fossil "worm" tubes from the class Tentaculita found from the Upper Ordovician to the Middle Jurassic (Bathonian) around the world. They have lamellar calcitic shells, usually with pseudopunctae or punctae and a bulb-like origin. Many were long misidentified as the polychaete annelid ''Spirorbis'' until studies of shell microstructure and formation showed significant differences. All pre-Cretaceous "''Spirorbis''" fossils are now known to be microconchids. Their classification at the phylum level is still debated. Most likely they are some form of lophophorate, a group which includes phoronids, bryozoans and brachiopods. Microconchids may be closely related to the other encrusting tentaculitoid tubeworms, such as '' Anticalyptraea'', trypanoporids and cornulitids. Their habitat is more controversial. While there is a consensus that they were present in the seas and in brackish water, there is a debate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Devonian
The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian period at million years ago (Megaannum, Ma), to the beginning of the succeeding Carboniferous period at Ma. It is the fourth period of both the Paleozoic and the Phanerozoic. It is named after Devon, South West England, where rocks from this period were first studied. The first significant evolutionary radiation of history of life#Colonization of land, life on land occurred during the Devonian, as free-spore, sporing land plants (pteridophytes) began to spread across dry land, forming extensive coal forests which covered the continents. By the middle of the Devonian, several groups of vascular plants had evolved leaf, leaves and true roots, and by the end of the period the first seed-bearing plants (Pteridospermatophyta, pteridospermatophyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Upper Ordovician
The Late Ordovician is the third and final epoch of the Ordovician period, lasting million years and spanning from around 458.2 to 443.1 million years ago. The rocks associated with this epoch are referred to as the Upper Ordovician Series. At this time, Western and Central Europe and North America collided to form Laurentia, while glaciers built up in Gondwana, which was positioned over the South Pole. This caused a drop in global temperatures, resulting in "ice house" conditions. For most of this time, life continued to flourish, but at and near the end of the period, there were mass-extinction events that seriously affected planktonic forms like conodonts, graptolites, and some groups of trilobites (Agnostida and Pytchopariida, which completely died out, and the Asaphida which were much reduced). Brachiopods, bryozoans and echinoderms were also heavily affected, and the endocerid cephalopods died out completely, except for possible rare Silurian The Silurian ( ) is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Phoronid
Phoronids (Taxonomy (biology), taxonomic name Phoronida, sometimes called horseshoe worms) are a small phylum of marine animals that Filter feeder, filter-feed with a lophophore (a "crown" of tentacles), and build upright tubes of chitin to support and protect their soft bodies. They live in most of the oceans and seas, including the Arctic Ocean but excluding the Antarctic Ocean, and between the intertidal zone and about 400 meters down. Most adult phoronids are 2 cm long and about 1.5 mm wide, although the largest are 50 cm long. The name of the group comes from its type genus: ''Phoronis#Etymology, Phoronis''. Overview The bottom end of the body is an ampulla (a flask-like swelling), which anchors the animal in the tube and enables it to retract its body very quickly when threatened. When the lophophore is extended at the top of the body, cilia (little hairs) on the sides of the tentacles draw food particles to the mouth, which is inside and slightly to o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Palaeogeography, Palaeoclimatology, Palaeoecology
''Palaeogeography, Palaeoclimatology, Palaeoecology'' ("''Palaeo3''") is a peer-reviewed scientific journal publishing multidisciplinary studies and comprehensive reviews in the field of palaeoenvironmental geology. The journal is edited by Howard Falcon-Lang, Shuzhong Shen, Alex Dickson, Mary Elliot, Meixun Zhao, Lucia Angiolini. It was established in 1965 and is currently published by Elsevier. Indexing and abstracting ''Palaeogeography, Palaeoclimatology, Palaeoecology'' is indexed and abstracted in the following databases: According to the ''Journal Citation Reports'', ''Advance in Space Research'' has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 3.318. References External links * Elsevier academic journals English-language journals Ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Neues Jahrbuch Für Geologie Und Paläontologie
''Neues Jahrbuch für Geologie und Paläontologie'' is a peer-reviewed scientific journal covering research in geology and paleontology. The journal is published monthly, with 4 volumes per year. Abstracting and indexing The journal is abstracted and indexed in Science Citation Index Expanded and Current Contents. According to the ''Journal Citation Reports'', the journal has a 2019 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 0.981. References External links * Geology journals Publications established in 1807 English-language journals E. Schweizerbart academic journals Quarterly journals Paleontology journals {{paleontology-journal-stub es:Journal of Molluscan Studies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lethaia
''Lethaia'' is a quarterly peer-reviewed scientific journal of Earth science, covering research on palaeontology and stratigraphy. Now published by Scandinavian University Press, it was originally published by the International Commission on Stratigraphy. It is an official publication of the International Palaeontological Association and the International Commission on Stratigraphy. The journal had a 2012 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 2.488, ranking it 7th out of 48 journals in the category "Paleontology", though its IF has since declined. References External links * Paleontology journals Wiley-Blackwell academic journals English-language journals Academic journals established in 1968 Quarterly journals {{paleontology-journal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Journal Of The Geological Society
The ''Journal of the Geological Society '' is a peer-reviewed scientific journal published by the Geological Society of London. It covers research in all aspects of the Earth sciences. References External links * Proceedings of the Geological Society of London Vol 1 (1826–1833) to Vol 4 (1843–1845) available online at the Biodiversity Heritage Library The Biodiversity Heritage Library (BHL) is the world’s largest open-access digital library for biodiversity literature and archives. BHL operates as a worldwide consortium of natural history, botanical, research, and national libraries working ...The Quarterly journal of the Geological Society of London Vol 1 (1845) to Vol 72 (1923) available online at the Biodiversity Heritage Library Publications established in 1826 Geology journals Bimonthly journals Geological Society of London academic journals English-language journals Academic journals published by learned and professional societies 1826 establishments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Chondrichthyes
Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fish'', which have skeletons primarily composed of bone tissue. Chondrichthyes are aquatic vertebrates with paired fins, paired nares, placoid scales, conus arteriosus in the heart, and a lack of opercula and swim bladders. Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates. The class is divided into two subclasses: Elasmobranchii (sharks, rays, skates and sawfish) and Holocephali ( chimaeras, sometimes called ghost sharks, which are sometimes separated into their own class). Extant chondrichthyans range in size from the finless sleeper ray to the over whale shark. Anatomy Skeleton The skeleton is cartilaginous. The notochord is gradually replaced by a vertebral column during development, e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Xiphosura
Xiphosura (; , in reference to its sword-like telson) is an order of arthropods related to arachnids. They are more commonly known as horseshoe crabs (a name applied more specifically to the only extant family, Horseshoe crab, Limulidae). They first appeared in the Hirnantian (Late Ordovician). Currently, there are only four living species. Xiphosura contains one suborder, Xiphosurida, and several stem-genera. The group has hardly changed in appearance in hundreds of millions of years; the modern horseshoe crabs look almost identical to prehistoric genera and are considered to be living fossils. The most notable difference between ancient and modern forms is that the abdominal segments in present species are fused into a single unit in adults. Xiphosura were historically placed in the class Merostomata, although this term was intended to encompass also the Eurypterida, eurypterids, whence it denoted what is now thought to be an unnatural (paraphyletic) group (although this is a gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Permian
The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the sixth and last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the Perm Governorate, region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the Sauropsida, sauropsids (reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cornulitida
Cornulitida is an extinct order of encrusting animals from class Tentaculita, which were common around the globe in the Ordovician to Devonian oceans, and survived until the Carboniferous. Organisms that may be the oldest cornulitids have been found in Cambrian sediments of Jordan. Cornulitids had shells, and were subject to predation by boring and other means from the Ordovician onwards. Many survived attacks by predators. Several cornulitids were endobiotic symbionts in the stromatoporoids and tabulates. Their affinity is unknown; they have been placed in many phyla, and have been considered worms, corals, molluscs and more. They appear to be closely related to other taxa of uncertain affinity, including the microconchids, trypanoporids and tentaculitids. Gallery Cornulitids and bryozoan Bellevue.jpg, alt=Cornulitids and bryozoan Bellevue, Cornulitids on a bryozoan; Bellevue Member, Grant Lake Formation, northern Kentucky Conchicolites.jpg, ''Conchicolites'' sp. over ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Trypanoporida
Trypanoporida is an extinct order of encrusting animals within Class Tentaculita, which were common in Devonian oceans (Weedon, 1991). Their affinity is unknown; they have been placed among worms and corals. They appear to be closely related to other taxa of uncertain affinity, including the microconchids, cornulitids, and tentaculitids. Spirally coiled trypanoporids (Devonian) were most likely derived from the geologically older microconchids (Late Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...). References * Weedon, M.J. 1991. Microstructure and affinity of the enigmatic Devonian tubular fossil ''Trypanopora''. Lethaia 24:227-234. Tentaculita Devonian animals Late Devonian animals Devonian first appearances Devonian extinctions {{paleo-invertebrate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
