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Buenaspis Drawing
''Buenaspis'' is a genus of small ( long) nektaspid arthropod, that lived during the early Cambrian period.Budd, G.E (1999).A Nectaspid Arthropod from the Early Cambrian Sirius Passet Fauna, with a description of Retrodeformation based on Functional Morphology. ''Palaeontology'', 42(1):99–122 Fossil remains of ''Buenaspis'' were collected from the Lower Cambrian Sirius Passet ''Lagerstätte'' of North Greenland. ''Buenaspis'' looks like a soft eyeless trilobite. It has a headshield (or cephalon) slightly larger than the tailshield (pygidium), and in between them six thoracic body segments (somites). The genus is monotypic, its sole species being ''Buenaspis forteyi''. Etymology The name of the genus is derived from the Buen Formation, the deposit where the species was collected, and the Greek word ''aspis'' (shield). The species was named in honor of Richard Fortey, a famed paleontologist. Description ''Buenaspis forteyi'' is between 1 and 3 cm along the axis, appr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atdabanian
Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambrian Stage 2 and precedes Cambrian Stage 4, although neither its base nor top have been formally defined. The plan is for its lower boundary to correspond approximately to the first appearance of trilobites, about million years ago, though the globally asynchronous appearance of trilobites warrants the use of a separate, globally synchronous marker to define the base. The upper boundary and beginning of Cambrian Stage 4 is informally defined as the first appearance of the trilobite genera '' Olenellus'' or ''Redlichia'' around million years ago. Naming The International Commission on Stratigraphy has not officially named the 3rd stage of the Cambrian. The stage approximately corresponds to the "Atdabanian", which is used by geologists working in Siberia. Biostratigraphy The oldest trilobite known is '' Lemdadella'' which appears at the beginning of the ''Fallotaspis'' zone. The Cambrian rad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buen Formation
The Buen Formation is a geologic formation and Lagerstätte in Peary Land, North Greenland. The shale preserves fossils dating back to the Early Cambrian period (Atdabanian in the local timescale, about 520 to 513 Ma).Buen Formation at .org Description The oldest Cambrian series of the area was deposited in the and is poorly exposed in fragmentary, heavily metamorphosed outcrops in |
Prehistoric Arthropod Genera
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamellipedia
Lamellipedia is a proposed clade of arthropods that includes most trilobites (but not Agnostida) and their close relatives. Distinctive of the clade are the flat setae aligned in a comb-like structure on the exopod The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, plur .... References Arthropod taxonomy {{paleo-arthropod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naraoia
''Naraoia'' is a genus of small to average size (about 2-4½ cm long) marine arthropods within the family Naraoiidae, that lived from the early Cambrian to the late Silurian period. The species are characterized by a large alimentary system and sideways oriented antennas. Etymology The name is derived from Narao, the name of a group of small lakes in Cataract Brook canyon, above Hector on the Canadian Pacific Railway, British Columbia, Canada.Walcott, C.D. Middle Cambrian Branchiopoda, Malacostraca, Trilobita, and Merostomata. In: Cambrian Geology and Paleontology II. Smithsonian. 1914. s:Cambrian Geology and Paleontology/Volume 2/Middle Cambrian Branchiopoda, Malacostraca, Trilobita, and Merostomata History of the classification When the fossil was first discovered in Canada's Burgess Shale, it was believed to be a crustacean, such was the difference between this and other trilobites. Its continuous shield hid most of its structure, interfering with proper classification. Wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudonaraoia
''Pseudonaraoia'' is a genus of small (about long) marine arthropods within the family Naraoiidae, that lived during the late Middle Ordovician period (or Darriwillian epoch). The only species presently known is ''Pseudonaraoia hammanni'' (the genus is monotypic). Etymology The genus name indicates the likeness to the related genus Naraoia. The species was named in honor of Dr. Wolfgang Hammann (†2002), the outstanding German palaeontologist who studied both trilobites and naraoids. Description ''P. hammanni'' is almost flat (dorso-ventrally). The upper (or dorsal) side of the body consists of a non-calcified headshield (cephalon) and tailshield (pygidium) of about equal length, without any body segments in between. The body is strongly narrowed at the articulation between cephalon and pygidium. Both shields have a narrow border, reminiscent of some effaced agnostid trilobites Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Misszhouia
''Misszhouia'' is a genus of small to average sized (up to long) marine arthropods within the Naraoiidae family, that lived during the early Cambrian period. The only species presently known is ''Misszhouia longicaudata'' (the genus is monotypic) and the holotype was discovered in 1984. Etymology ''Misszhouia'' was named after "Miss Zhou" (Zhou Guiqin), to honour her for her skilled preparation of Chengjiang fossils. Description ''Misszhouia longicaudata'' is almost flat (dorso-ventrally). The upper (or dorsal) side of the body consists of a non-calcified headshield ( cephalon) and tailshield ( pygidium) without body segments between. The body is narrowed at the articulation between cephalon and pygidium. The long many-segmented antennae are directed forward. There are no eyes. The gut has a relatively small diameter, and there are four pairs of relatively small digestive sacs (or caeca) in the cephalon only, and no branches towards the edge of the cephalon (unlike '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liwiidae
Liwiidae is a family of arthropods in the order Nektaspida. Members are known from the Cambrian and Ordovician periods. Taxonomy *''Liwia'' Dzik and Lendzion, 1988 :*''Liwia plana'' Lendzion, 1975 :*''Liwia convexa'' Lendzion, 1975 *''Soomaspis'' Fortey & Theron, 1995 :*''Soomaspis splendida'' Fortey & Theron, 1995 *''Tariccoia'' Hammann ''et al.'', 1990 :*''Tariccoia arrusensis ''Tariccoia'' is a genus of nektaspid arthropods belonging to the family Liwiidae, known from fossils found in Ordovician strata in Sardinia and Morocco. It is between and long. It has a headshield (or cephalon) wider than the tailshield (pygi ...'' Hammann ''et al.'', 1990 References Nektaspida Prehistoric arthropod families Cambrian first appearances Ordovician first appearances {{nektaspida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soomaspis Splendida
''Soomaspis'' is a genus of small to average size (about 3 cm or 1.2-inch long) marine arthropods in the Liwiidae Family, that lived during the late Ordovician (early Hirnantian). Fossil remains of ''Soomaspis'' were collected from the Soom Shale Lagerstätte in Western Cape, South Africa. ''Soomaspis'' looks like a large, soft agnostid trilobite. It has a headshield (or cephalon) wider than the tailshield (pygidium), and in between them three thoracic body segments (somites). The genus is monotypic, its sole species being ''Soomaspis splendida''. Etymology The name of the genus is a compound word of the deposit where the species was collected (the Soom Shale), and the Greek word ''"aspis"'' (shield). The species epithet, ''splendida'' comes from the Latin word ''"splendere"'' (brightness). Description ''Soomaspis splendida'' is estimated to be over 3 cm (1.2 inches) along the axis,L. Ramskold, J.-Y. Chen, G.D. Edgecombe, and G.-Q. Zhou (1996). "Preservational fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tariccoia
''Tariccoia'' is a genus of nektaspid arthropods belonging to the family Liwiidae, known from fossils found in Ordovician strata in Sardinia and Morocco. It is between and long. It has a headshield (or cephalon) wider than the tailshield (pygidium), and in between them three (or four?) thoracic body segments (somites). Etymology The name of the genus references the Sardinian paleontologist M. Taricco. The species was named after the Riu is Arrus Member, the deposit in which it was found. Description ''Tariccoia arrusensis'' is between 2.5 and 6 cm along the axis, almost half a wide as long. The dorsal exoskeleton consists of a cephalon, a pygidium and two or three thoracic somites with articulating half-rings, all non-calcified. The cephalon is sub-semicircular, widest near the rounded genal angles. The cephalon is wider than the pygidium. Eyes are absent. Antennas are not known. The body is constricted at the two or three thoracic somites, so the animal gives the im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liwia
''Liwia'' is a genus of nektaspid, a soft-bodied stem-group chelicerate. It includes the following species, both are known from borehole samples several kilometers in depth from the Zawiszyn Formation in Poland, which has also yielded ''Peytoia infercambriensis ''Peytoia infercambriensis'' is a species of hurdiid radiodont in the genus ''Peytoia''. ''P. infercambriensis'' is the geologically oldest known radiodont; its remains date to the third age of the Cambrian. The type and only known specimen, ....'' *''Liwia plana'' Lendzion, 1975 *''Liwia convexa'' Lendzion 1975 References Nektaspida Fossils of Poland {{nektaspida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exoskeleton
An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton ( endoskeleton) in for example, a human. In usage, some of the larger kinds of exoskeletons are known as " shells". Examples of exoskeletons within animals include the arthropod exoskeleton shared by chelicerates, myriapods, crustaceans, and insects, as well as the shell of certain sponges and the mollusc shell shared by snails, clams, tusk shells, chitons and nautilus. Some animals, such as the turtle, have both an endoskeleton and an exoskeleton. Role Exoskeletons contain rigid and resistant components that fulfill a set of functional roles in many animals including protection, excretion, sensing, support, feeding and acting as a barrier against desiccation in terrestrial organisms. Exoskeletons have a role in defense from pests and predators, support and in providing an attachment framewo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
