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Comptonia (sea Star)
''Comptonia'' is an extinct genus of prehistoric sea stars in the family Goniasteridae Goniasteridae (the biscuit stars) constitute the largest family of sea stars, included in the order Valvatida. They are mostly deep-dwelling species, but the family also include several colorful shallow tropical species. Description Goni .... Species are from the Cretaceous of Canada (Alberta) and France. The type species, ''C. elegans'' (syn. ''Goniaster (Stellaster) elegans'', ''Stellaster elegans'') was recovered from France. References External links * * Prehistoric starfish genera Goniasteridae Fossils of Canada Fossils of France {{Cretaceous-animal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goniasteridae
Goniasteridae (the biscuit stars) constitute the largest family of sea stars, included in the order Valvatida. They are mostly deep-dwelling species, but the family also include several colorful shallow tropical species. Description Goniasteridae are usually middle-sized sea stars with a characteristic double range of marginal plates bordering the disk and arms. Most of them have five arms, often short and triangular, around a broad central disc; many species are pentagonal or subpentagonal, covered densely with granular, seed-like protuberances, hence the name of the family "seed-star" (''gonium+aster''). The aboral face is often covered with tiny spines looking like paxillae. Pedicellariae are often valvate, and the gonads are located at the interradius. Main identification keys for this group include the presence of paxillae, granules, teeth, spines, or the shape and dimensions of marginal plate. Location and habitat They occur predominantly on deep-water continenta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Starfish 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] |
Fossils Of Canada
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
