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Kokomopteroidea
Kokomopteroidea is an extinct superfamily of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". It is one of four superfamilies classified as part of the suborder Stylonurina. Kokomopteroids have been recovered from deposits of Early Silurian to Late Devonian age in the United States and the United Kingdom. Description Kokomopteroids are stylonurines with a spiniferous appendage V and a posterior notch on the metastoma. The superfamily forms two distinct clades; the Kokomopteridae (including the genera '' Kokomopterus'' and '' Lamontopterus'') and the Hardieopteridae (including the genera '' Hardieopterus'', '' Tarsopterella'' and '' Hallipterus''). The Kokomopteroidea retains primitive ''Hughmilleria''-type prosomal appendages for unsuitable raking through the bottom sediments of marine environments. As such, the members of the superfamily were likely scavengers. The Hardieopteridae display some sweep-feeding characteristics similarl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylonurina
Stylonurina is one of two suborders of eurypterids, a group of extinct arthropods commonly known as "sea scorpions". Members of the suborder are collectively and informally known as "stylonurine eurypterids" or "stylonurines". They are known from deposits primarily in Europe and North America, but also in Siberia. Compared to the other suborder, Eurypterina, the stylonurines were comparatively rare and retained their posterior prosomal appendages for walking. Despite their rarity, the stylonurines have the longest temporal range of the two suborders. The suborder contains some of the oldest known eurypterids, such as ''Brachyopterus'', from the Middle Ordovician as well as the youngest known eurypterids, from the Late Permian. They remained rare throughout the Ordovician and Silurian, though the radiation of the mycteropoids (a group of large sweep-feeding forms) in the Late Devonian and Carboniferous is the last major radiation of the eurypterids before their extinction in the Pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hibbertopteroidea
Mycteropoidea is an extinct superfamily of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". It is one of four superfamilies classified as part of the suborder Stylonurina. Mycteropoids have been recovered from Europe, Russia, South America and South Africa. Mycteropoid specimens are often fragmentary, making it difficult to establish relationships between the included taxa. Only two mycteropoid taxa are known from reasonable complete remains, ''Hibbertopterus scouleri'' and ''H. wittebergensis''. Mycteropoids were large bizarre Eurypterids found from the Early Silurian to the end of the Permian period. They were sweep feeders, inhabiting freshwater swamps and rivers, feeding by raking through the soft sediment with blades on their anterior appendages to capture small invertebrates. Their morphology was so unusual that they have been thought to be an order separate to Eurypterida. Recent work however confirms them to be derived members of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kokomopteridae
The Kokomopteridae are a family of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". The family is one of two families contained in the superfamily Kokomopteroidea (along with Hardieopteridae), which in turn is one of four superfamilies classified as part of the suborder Stylonurina. Kokomopterids are defined as kokomopteroids with an undifferentiated opisthosoma with a marginal rim. Appendages II-V are spiniferous as in '' Lamontopterus'' and VI is non-spiniferous as in ''Kokomopterus''. The Kokomopteridae retains primitive ''Hughmilleria''-type prosomal appendages II-IV, unsuited to the sweep-feeding lifestyle used by some of the superfamilies of the Stylonurina (Stylonuroidea and Hibbertopteroidea), and were as such likely mainly scavengers. Genera Family Kokomopteridae Kjellesvig-Waering, 1966 * ''Kokomopterus ''Kokomopterus'' is a genus of prehistoric eurypterid. The genus contains a single species, ''Kokomopterus longicaudat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardieopteridae
The Hardieopteridae are a family of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". The family is one of two families contained in the superfamily Kokomopteroidea (along with Kokomopteridae), which in turn is one of four superfamilies classified as part of the suborder Stylonurina. Hardieopterids have been recovered from deposits of Early Silurian to Late Devonian age in the United States and the United Kingdom. Hardieopterids are defined as kokomopteroids with lateral pleurae on their metastoma and pretelson, large lunate scales on the posterior margin of the carapace and a clavate telson. The opisthosoma shows both a second and fourth order differentiation into a mesosoma and metasoma. Appendages II-IV are unknown, though appendage V is spiniferous and VI is non-spiniferous as in the genus '' Hardieopterus''. The Hardieopteridae display some adaptations towards sweep-feeding, such as a broadening of the metastoma and the spines of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurypterid
Eurypterids, often informally called sea scorpions, are a group of extinct arthropods that form the Order (biology), order Eurypterida. The earliest known eurypterids date to the Darriwilian stage of the Ordovician period 467.3 Myr, million years ago. The group is likely to have appeared first either during the Early Ordovician or Late Cambrian period. With approximately 250 species, the Eurypterida is the most diverse Paleozoic Chelicerata, chelicerate order. Following their appearance during the Ordovician, eurypterids became major components of marine faunas during the Silurian, from which the majority of eurypterid species have been described. The Silurian genus ''Eurypterus'' accounts for more than 90% of all known eurypterid specimens. Though the group continued to diversify during the subsequent Devonian period, the eurypterids were heavily affected by the Late Devonian extinction event. They declined in numbers and diversity until becoming extinct during the Permian–Tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drepanopterus
''Drepanopterus'' is an extinct genus of eurypterid and the only member of the family Drepanopteridae within the Mycteropoidea superfamily. There are currently three species assigned to the genus. The genus has historically included more species, with nine species associated with the genus ''Drepanopterus'', however five of these have since been proven to be synonyms of pre-existing species, assigned to their own genera, or found to be based on insubstantial fossil data. The holotype of one species proved to be a lithic clast. ''Drepanopterus pentlandicus'' was first described from the Silurian strata of the Pentland Hills in Scotland. The only other fully described valid species is ''Drepanopterus abonensis'', from the Upper Devonian of Portishead, Somerset. The exact relationship of ''Drepanopterus'' to other Eurypterids has long been unclear, however it is now apparent that it is a primitive mycteropoid, and an early relative of the Carboniferous ''Hibbertopterus''. Descripti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hallipterus
''Hallipterus'' is a genus of prehistoric eurypterid classified as part of the family Hardieopteridae. Description ''Hallipterus'' was a gigantic Hardieopterid eurypterid. Though some previous estimates have placed its size at over 1.5 meters in length, these were likely excessive. Still, assigned specimens suggest a size of over 1 meter long. The carapace was subelliptical, greater in length than in width, with a prominent and unornamented marginal rim. The eyes were very small, close to each other and separated by a prominent median ridge with large ocelli at the posterior extremity. The chelicerae were simple and elongated. The first walking legs possessed flat and movable spines. The rest of the legs and the opisthosoma remain unknown. Species ''Hallipterus'' contains one valid species, ''H. excelsior'', from the Devonian of New York.Dunlop, J. A., Penney, D. & Jekel, D. 2015. A summary list of fossil spiders and their relatives. In World Spider Catalog. Natural Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian First Appearances
The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoic Era. As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out. One important event in this period was the initial establishment of terrestrial life in what is known as the Silurian-Devonian Terrestrial Revolution: vascular plants emerged from more primitive land plants, dikaryan fungi started expanding and diversifying along with glomeromycotan fungi, and three groups of arthropods (myriapods, arachnids and hexapods) became fully terrestrialized. A significant evolutionary milestone during th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian
The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoic Era. As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out. One important event in this period was the initial establishment of terrestrial life in what is known as the Silurian-Devonian Terrestrial Revolution: vascular plants emerged from more primitive land plants, dikaryan fungi started expanding and diversifying along with glomeromycotan fungi, and three groups of arthropods (myriapods, arachnids and hexapods) became fully terrestrialized. A significant evolutionary milestone during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylonuroidea
Stylonuroidea is an extinct superfamily of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". It is one of four superfamilies classified as part of the suborder Stylonurina. Stylonuroidea, which lived from the Early Silurian to the Late Devonian, were characterized by their last pair of prosomal (head) appendages, which were developed as walking legs, or less commonly developed as swimming legs with paddles formed by the expansion of the two or three penultimate joints. 1955. Merostomata. ''Treatise on Invertebrate Paleontology, Part P Arthropoda 2, Chelicerata'', P36. as Stylonuracea Description Stylonuroids are designated as stylonurines with flattened or truncated posterior metastomata margins. Of the four stylonurine superfamilies, the Stylonuroidea is the most poorly known. Whilst the topology of most stylonurine clades fit well with the stratigraphic record, Stylonuroidea is an exception in that the earliest record of the most der ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scavenger
Scavengers are animals that consume dead organisms that have died from causes other than predation or have been killed by other predators. While scavenging generally refers to carnivores feeding on carrion, it is also a herbivorous feeding behavior. Scavengers play an important role in the ecosystem by consuming dead animal and plant material. ''Decomposers'' and detritivores complete this process, by consuming the remains left by scavengers. Scavengers aid in overcoming fluctuations of food resources in the environment. The process and rate of scavenging is affected by both biotic and abiotic factors, such as carcass size, habitat, temperature, and seasons. Etymology Scavenger is an alteration of ''scavager,'' from Middle English ''skawager'' meaning "customs collector", from ''skawage'' meaning "customs", from Old North French ''escauwage'' meaning "inspection", from ''schauwer'' meaning "to inspect", of Germanic origin; akin to Old English ''scēawian'' and German ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
