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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] |
Drepanopterus Size
''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] |
Hibbertopterus
''Hibbertopterus'' is a genus of eurypterid, a group of extinct aquatic arthropods. Fossils of ''Hibbertopterus'' have been discovered in deposits ranging from the Devonian period in Belgium, Scotland and the United States to the Carboniferous period in Scotland, Ireland, the Czech Republic and South Africa. The type species, ''H. scouleri'', was first named as a species of the significantly different ''Eurypterus'' by Samuel Hibbert in 1836. The generic name ''Hibbertopterus'', coined more than a century later, combines his name and the Greek word πτερόν (''pteron'') meaning "wing". ''Hibbertopterus'' was the largest eurypterid within the stylonurine suborder, with the largest fossil specimens suggesting that ''H. scouleri'' could reach lengths around 180–200 centimetres (5.9–6.6 ft). Though this is significantly smaller than the largest eurypterid overall, ''Jaekelopterus'', which could reach lengths of around , ''Hibbertopterus'' is likely to have been the h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycteropoidea
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 o ... [...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] |
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] |
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] |
List Of Eurypterids
This list of eurypterid genera is a comprehensive listing of all genera that have ever been included in the order Eurypterida, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful ('' nomen dubium''), or were not formally published ('' nomen nudum''), as well as junior synonyms of more established names and genera that are no longer considered eurypterids. The list currently includes 115 names out of which 74 are considered valid eurypterid genera. There are approximately 250 species of eurypterids recognized as valid. Naming conventions and terminology There is no "official" or "canonical" list of eurypterid genera. The closest thing is found contained in the regularly updated ''Summary list'' ''of fossil spiders and their relatives'' in the World Spider Catalog. The vast majority of the content of the list below, including the valid genera, preoccupied names, junior synonyms, taxonomical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megarachne
''Megarachne'' is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of ''Megarachne'' have been discovered in deposits of Late Carboniferous age, from the Gzhelian stage, in San Luis, Argentina. The fossils of the single and type species ''M. servinei'' have been recovered from deposits that had once been a freshwater environment. The generic name, composed of the Ancient Greek μέγας (''megas'') meaning "great" and Ancient Greek ἀράχνη (''arachne'') meaning "spider", translates to "great spider", because the fossil was misidentified as a large prehistoric spider. With a body length of , ''Megarachne'' was a medium-sized eurypterid. If the original identification as a spider had been correct, ''Megarachne'' would have been the largest known spider to have ever lived. Eurypterids such as ''Megarachne'' are often called "sea scorpions", but the strata in which ''Megarachne'' has been found indicates that it dwelled in freshwater and not in marine e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Eurypterina
Eurypterina is one of two suborders of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". Eurypterine eurypterids are sometimes informally known as "swimming eurypterids". They are known from fossil deposits worldwide, though primarily in North America and Europe. Seventy-five percent of eurypterid species are eurypterines; this represents 99% of specimens. The superfamily Pterygotioidea is the most species-rich clade, with 56 species, followed by the Adelophthalmoidea with 43 species; as sister taxa, they comprise the most derived eurypterines. Pterygotioidea includes the pterygotids, which are the only eurypterids known to have a cosmopolitan distribution. Though more numerous both in specimens and taxa, the eurypterines have the shorter temporal range of the two eurypterid suborders. They first appeared around the same time as the Stylonurina in the Middle Ordovician. The suborder faced a slow extinction during the Middle and Late Devo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanahughmilleria
''Nanahughmilleria'' ("dwarf ''Hughmilleria''") is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of ''Nanahughmilleria'' have been discovered in deposits of Devonian and Silurian age in the United States, Norway, Russia, England and Scotland, and have been referred to several different species. ''Nanahughmilleria'' is classified in the family Adelophthalmidae, the only clade in the superfamily Adelophthalmoidea. This clade was characterised by their small size, their parabolic (approximately U-shaped) carapaces and the presence of epimera (lateral "extensions" of the segment) on the seventh segment, among others. ''Nanahughmilleria'' was different from its relatives by the presence of more spines in its appendages (limbs) and by its genital morphology. The largest species confidently assigned to the genus was ''N. norvegica'' at 10 cm (3.9 in), making it a comparatively small eurypterid. Description Like the other adelophthalmid eurypterids, ''Nanahug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
