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Dalmanites
''Dalmanites'' is a genus of trilobite in the order Phacopida. They lived from the Late Ordovician to Middle Devonian. The trilobites of this genus have slightly convex exoskeletons with an average length of . The cephalon is semicircular or parabolic. The glabella (center portion of the head) is often pear-shaped, and tapers outward toward the front. The glabella also always contains three pairs of obvious glabellar furrows. Also prominent are the large mosaic (schizochroal) eyes. The thorax is composed of eleven segments, with the relatively large pygidium with a slender axis of 11 to 16 rings and 6 or 7 pleural ribs. The pygidium ends in a striking tail spike. Taxonomy Species previously assigned to ''Dalmanites'' Some species formerly included in ''Dalmanites'' have now been reassigned to other genera. * ''D. lapeyrei'' = '' Zeliszkella torrubiae'' * ''D. maecurua'' = ''Amazonaspis maecurua'' * ''D. micheli'' = '' Phacopidina micheli'' * ''D. pleione'' = '' Bellacartwr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dalmanitidae
Dalmanitidae is a family of trilobites in the order Phacopida that lived from the Floian (Ordovician) to the Devonian and includes 33 genera. References Dalmanitidae, Dalmanitoidea Trilobite families Early Ordovician first appearances Devonian extinctions Fossils of Georgia (U.S. state) {{phacopida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite
Trilobites (; meaning "three-lobed entities") are extinction, extinct marine arthropods that form the class (biology), class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most successful of all early animals, existing in oceans for almost 270million years, with over 22,000 species having been described. Because trilobites had wide diversity and an easily fossilized mineralised exoskeleton made of calcite, they left an extensive fossil record. The study of their fossils has facilitated important contributions to biostratigraphy, paleontology, evolution, evolutionary biology, and plate tectonics. Trilobites are placed within the clade Artiopoda, which includes many organisms that are morphologically similar to trilobites, but are largely unmineralised. The relationship of Artiopoda to other arthropods is uncertain. Trilobites evolved into many ecological niches; some moved over the seabed as predators, scavengers, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian Trilobites
The Silurian ( ) is a geologic period and system spanning 23.5 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 third and shortest period of the Paleozoic Era, and the third of twelve periods of the Phanerozoic Eon. 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 full ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coalbrookdale Formation
Coalbrookdale Formation, earlier known as Wenlock Shale or Wenlock Shale Formation and also referred to as Herefordshire Lagerstätte in palaeontology, is a fossil-rich deposit ('' Konservat-Lagerstätte'') in Powys and Herefordshire at the England–Wales border in UK. It belongs to the Wenlock Series of the Silurian Period within the Homerian Age (about 430 million years ago). It is known for its well-preserved fossils of various invertebrate animals many of which are in their three-dimensional structures. Some of the fossils are regarded as earliest evidences and evolutionary origin of some of the major groups of modern animals. Roderick Murchison first described the geological setting of Coalbrookdale Formation by which he gave the name Silurian in 1935, referring to the Silures, a Celtic tribe of Wales. It is assigned to the Wenlock Group in 1978 based on the age of crustacean fossils found around the region. Robert J. King of the University of Leicester discovered the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite
Trilobites (; meaning "three-lobed entities") are extinction, extinct marine arthropods that form the class (biology), class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most successful of all early animals, existing in oceans for almost 270million years, with over 22,000 species having been described. Because trilobites had wide diversity and an easily fossilized mineralised exoskeleton made of calcite, they left an extensive fossil record. The study of their fossils has facilitated important contributions to biostratigraphy, paleontology, evolution, evolutionary biology, and plate tectonics. Trilobites are placed within the clade Artiopoda, which includes many organisms that are morphologically similar to trilobites, but are largely unmineralised. The relationship of Artiopoda to other arthropods is uncertain. Trilobites evolved into many ecological niches; some moved over the seabed as predators, scavengers, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phacopida
Phacopida ("lens-face") is an order of trilobites that lived from the Late Cambrian to the Late Devonian. It is made up of a morphologically diverse assemblage of taxa in three related suborders. Characteristics Phacopida had 8 to 19 thoracic segments and are distinguishable by the expanded glabella, short or absent preglabellar area, and schizochroal (Phacopina) or holochroal (Cheirurina and Calymenina) eyes. Schizochroal eyes are compound eyes with up to around 700 separate lenses. Each lens has an individual cornea which extended into a rather large sclera. The development of schizochroal eyes in phacopid trilobites is an example of post-displacement paedomorphosis. The eyes of immature holochroal Cambrian trilobites were basically miniature schizochroal eyes. In Phacopida, these were retained, via delayed growth of these immature structures (post-displacement), into the adult form. '' Eldredgeops rana'' (Phacopidae) and '' Dalmanites limulurus'' (Dalmanitidae) are two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobus
''Trilobus'' Bruennich, 1781 is a disused genus of trilobites, the species of which are now all assigned to other genera. * ''T. caudatus'' = '' Dalmanites caudatus'' * ''T. punctatus'' Bruennich, 1781 = '' Encrinurus punctatus'' ''Trilobus'' Bastian, 1865 is also the preoccupied name of several nematodes belonging to the subfamily Tobrilinae, that have been renamed to ''Tobrilus'' and some have since been reassigned to other genera. * ''T. aequiseta'' = ''Tobrilus aequiseta'' * ''T. allophysioides'' = ''Tobrilus altherri'' or ''T. helveticus'' * ''T. allophysis'' = ''Tobrilus allophysis'' * ''T. armatus'' = ''Tobrilus armatus'' * ''T. biroi'' = ''Tobrilus biroi'' * ''T. brevisetosus'' = ''Tobrilus brevisetosus'' * ''T. dryophilus'' = ''Tobrilus dryophilus'' * ''T. consimilis'' = ''Epitobrilus stefanskii'' * ''T. gracilis'' = ''Tobrilus gracilis'' * ''T. graciloides'' = ''Epitobrilus graciloides'' * ''T. grandipapilloides'' = ''Paratrilobus grandipapilloides'' * ''T. hoehnelen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobites Of North America
Trilobites (; meaning "three-lobed entities") are extinct marine arthropods that form the class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most successful of all early animals, existing in oceans for almost 270million years, with over 22,000 species having been described. Because trilobites had wide diversity and an easily fossilized mineralised exoskeleton made of calcite, they left an extensive fossil record. The study of their fossils has facilitated important contributions to biostratigraphy, paleontology, evolutionary biology, and plate tectonics. Trilobites are placed within the clade Artiopoda, which includes many organisms that are morphologically similar to trilobites, but are largely unmineralised. The relationship of Artiopoda to other arthropods is uncertain. Trilobites evolved into many ecological niches; some moved over the seabed as predators, scavengers, or filter feeders, and some swam, feeding o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeliszkella
''Zeliszkella'' is a genus of trilobite in the order Phacopida, with species of average size. Species are known from the Middle and Upper Ordovician and have been found in the Czech Republic, France, Morocco, Portugal and Spain. The cephalon has a rather narrow frontal area, and the anterior sections of the facial sutures run close to frontal lobe anteriorly. The large mosaic ( schizochroal) eyes reach far backward. The main body (or thorax) is composed of eleven segments. The side lobes (pleurae) of the thorax curve stronger backward closer to the tail shield (or pygidium The pygidium (: pygidia) is the posterior body part or shield of crustaceans and some other arthropods, such as insects and the extinct trilobites. In groups other than insects, it contains the anus and, in females, the ovipositor. It is compos ...), their pointed tips longer than those of anterior pleurae. The pygidium is elongate subtriangular with the axis narrowly triangular reaching the back of the py ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bellacartwrightia
''Bellacartwrightia'' is a relatively uncommon genus of phacopid trilobite, found in the mid-Devonian Hamilton Group of New York state, mainly in strata exposed near Lake Erie just west of Buffalo Buffalo most commonly refers to: * True buffalo or Bubalina, a subtribe of wild cattle, including most "Old World" buffalo, such as water buffalo * Bison, a genus of wild cattle, including the American buffalo * Buffalo, New York, a city in the n .... This trilobite is usually about 1.5" to 2" long. A very similar trilobite from the Devonian of Morocco is still sold as ''Metacanthina'', but considerable research is still being done on Moroccan trilobites. References *Brett, Carlton, et al., ''Trilobites of New York''. Rochester: Rochester University Press, 2003. Devonian trilobites of North America Acastidae Fossils of the United States Phacopida genera {{Phacopida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian Trilobites
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] |
