| 释义 |
Definition of rudist in English: rudist(also rudistid) noun ˈruːdɪstˈrudɪst A cone-shaped fossil bivalve mollusc which formed colonies resembling reefs in the Cretaceous period. Superfamily Rudistacea, order Hippuritoida Example sentencesExamples - Aptian reefs were typically composed of rudists.
- This member contains abundant and diverse mid-Cretaceous shallow-marine invertebrates, including reef corals and rudist bivalves.
- Data from the Pacific Ocean on the distribution of rudists on carbonate platforms confirm that biocalcification crises in shallow-water settings were truly global.
- The limestone clasts contain rudist fragments and larger foraminifera that indicate erosion from the Campur Formation.
- The seas were inhabited by large ammonoids like Olcostephanus, bivalves like Bruchia, and (in selected areas) some of the early rudist reefs.
- Many rudist species were defined on specimens collected from the El Abra Formation in Mexico, a widespread carbonate platform.
- Most of the characteristic life forms of the Cretaceous had not yet evolved or were insignificant, including angiosperms, mosasaurs, therian mammals, hadrosaurs, rudists, calcareous plankton and planktonic foraminifera.
- Most of the rudist species listed by these authors are typical late Albian taxa, but their purported occurrences here require additional study and supportive documentation.
- An extinct group of Mesozoic bivalves, the rudistids, became closely adapted to a cemented mode of life: one valve became conical while the other formed a lid.
- Cretaceous radiations of rudists were apparently initiated during periods of globally high sea level and the Lebanon decapod faunas are a part of this general increasing invertebrate diversity.
- These two species are not as yet known to be associated with rudists or corals, although a few specimens of both rudists and corals have been recovered from other localities of Turonian age in the Santa Ana Mountains.
Origin Late 19th century: from modern Latin Rudista (former group name), from Latin rudis 'rude'; for the variant spelling see -id3. Definition of rudist in US English: rudist(also rudistid) nounˈro͞odistˈrudɪst A cone-shaped extinct bivalve mollusk that formed colonies resembling reefs in the Cretaceous period. Superfamily Rudistacea, order Hippuritoida Example sentencesExamples - Most of the characteristic life forms of the Cretaceous had not yet evolved or were insignificant, including angiosperms, mosasaurs, therian mammals, hadrosaurs, rudists, calcareous plankton and planktonic foraminifera.
- An extinct group of Mesozoic bivalves, the rudistids, became closely adapted to a cemented mode of life: one valve became conical while the other formed a lid.
- Aptian reefs were typically composed of rudists.
- This member contains abundant and diverse mid-Cretaceous shallow-marine invertebrates, including reef corals and rudist bivalves.
- The limestone clasts contain rudist fragments and larger foraminifera that indicate erosion from the Campur Formation.
- These two species are not as yet known to be associated with rudists or corals, although a few specimens of both rudists and corals have been recovered from other localities of Turonian age in the Santa Ana Mountains.
- Most of the rudist species listed by these authors are typical late Albian taxa, but their purported occurrences here require additional study and supportive documentation.
- The seas were inhabited by large ammonoids like Olcostephanus, bivalves like Bruchia, and (in selected areas) some of the early rudist reefs.
- Cretaceous radiations of rudists were apparently initiated during periods of globally high sea level and the Lebanon decapod faunas are a part of this general increasing invertebrate diversity.
- Data from the Pacific Ocean on the distribution of rudists on carbonate platforms confirm that biocalcification crises in shallow-water settings were truly global.
- Many rudist species were defined on specimens collected from the El Abra Formation in Mexico, a widespread carbonate platform.
Origin Late 19th century: from modern Latin Rudista (former group name), from Latin rudis ‘rude’; for the variant spelling see -id. |