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Panulirus Echinatus
''Panulirus echinatus'', the brown spiny lobster, is a species of spiny lobster that lives on rocky reefs in the tropical western Atlantic Ocean and central Atlantic Islands. Description Like other spiny lobsters, ''Panulirus echinatus'' has no pincer-like chelae on its front walking legs. It differs from related species by having just two large spines on the antennular plate, just in front of the carapace, and the exopod of the third feeding appendage is reduced and bears no flagellum. The basic colour is brown with large white rounded spots. The antennules and limbs are brown and have longitudinal white or yellow markings. The average size varies over different parts of its range, with males growing to a carapace length of about and females . Males are in general more numerous, larger and heavier than females but this may be because of behavioural differences, with females feeding less during the breeding season. Distribution and habitat ''Panulirus echinatus'' is found off ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidney Irving Smith
Sidney Irving Smith (February 18, 1843 in Norway, Maine – May 6, 1926 in New Haven, Connecticut) was an American zoologist. Private life Sidney Smith was the son of Elliot Smith and Lavinia Barton. His brother in law was Addison Emery Verrill. Smith married Eugenia Pocahontas Barber in New Haven, Connecticut on June 29, 1882. The couple had no children, and Eugenia died on March 14, 1916. Smith suffered from hereditary glaucoma, rendering him partially sighted from 1906, and completely blind some years before his death. He died on May 6, 1926 of throat cancer. Education and career In his youth, Sidney Irving Smith became expert on the fauna around his home town, and an expert at making collections, particularly of insects. He studied at the Sheffield Scientific School of Yale University, and received his Ph.B. in 1867. Yale University conferred upon him the honorary degree of M.A. in 1887. He stayed on at Yale, initially as an assistant, but from 1875 as the first professor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coralline Alga
Coralline algae are red algae in the order Corallinales. They are characterized by a thallus that is hard because of calcareous deposits contained within the cell walls. The colors of these algae are most typically pink, or some other shade of red, but some species can be purple, yellow, blue, white, or gray-green. Coralline algae play an important role in the ecology of coral reefs. Sea urchins, parrot fish, and limpets and chitons (both mollusks) feed on coralline algae. In the temperate Mediterranean Sea, coralline algae are the main builders of a typical algal reef, the ''Coralligène'' ("coralligenous"). Many are typically encrusting and rock-like, found in marine waters all over the world. Only one species lives in freshwater. Unattached specimens (maerl, rhodoliths) may form relatively smooth compact balls to warty or fruticose thalli. A close look at almost any intertidal rocky shore or coral reef will reveal an abundance of pink to pinkish-grey patches, distributed throug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edible Crustaceans
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans ( Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustaceans Of The Atlantic Ocean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Achelata
The Achelata is an infra-order of the decapod crustaceans, holding the spiny lobsters, slipper lobsters and their fossil relatives. Description The name "Achelata" derives from the fact that all the members of this group lack the chelae (claws) that are found on almost all other decapods (from the Ancient Greek , = "not", , = "claw"). They are further united by the great enlargement of the second antennae, by the special "phyllosoma" form of the larva, and by a number of other characters. Classification and fossil record The infraorder Achelata belongs to the group Reptantia, which consists of the walking/crawling decapods (lobsters and crabs). The cladogram below shows Achelata's placement within the larger order Decapoda, from analysis by Wolfe ''et al.'', 2019. Achelata contains the spiny lobsters (Palinuridae), the slipper lobsters (Scyllaridae) and the furry lobsters (Synaxidae, now usually included in Palinuridae), as well as two extinct families, Cancrinidae a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Least-concern Species
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent. Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status. Evaluation Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the "Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15636) in the IUCN database still use the code "LR/lc", which indicates they have not been re-evaluate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union For Conservation Of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partnerships. The organization is best known to the wider pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fecundity
Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to produce offspring, measured by the number of gametes (eggs), seed set, or asexual propagules. Superfecundity refers to an organism's ability to store another organism's sperm (after copulation) and fertilize its own eggs from that store after a period of time, essentially making it appear as though fertilization occurred without sperm (i.e. parthenogenesis). Human demography Human demography considers only human fecundity, at its culturally differing rates, while population biology studies all organisms. The term ''fecundity'' in population biology is often used to describe the rate of offspring production after one time step (often annual). In this sense, fecundity may include both birth rates and survival of young to that time step. Whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosomal DNA
Ribosomal DNA (rDNA) is a DNA sequence that codes for ribosomal RNA. These sequences regulate transcription initiation and amplification, and contain both transcribed and non-transcribed spacer segments. In the human genome there are 5 chromosomes with nucleolus organizer regions: the acrocentric chromosomes 13 (RNR1), 14 ( RNR2), 15 ( RNR3), 21 (RNR4) and 22 (RNR5). The genes that are responsible for encoding the various sub-units of rRNA are located across multiple chromosomes in humans. But the genes that encode for rRNA are highly conserved across the domains, with only the copy numbers involved for the genes having varying numbers per species. In Bacteria, Archaea, and chloroplasts the rRNA is composed of different (smaller) units, the large (23S) ribosomal RNA, 16S ribosomal RNA and 5S rRNA. The 16S rRNA is widely used for phylogenetic studies. Eukaryotes The rRNA transcribed from the approximately 600 rDNA repeats forms the most abundant section of RNA found in cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllosoma
The phyllosoma is the larval stage of spiny, slipper and coral lobsters (Palinuridae, Scyllaridae and Synaxidae), and represents one of the most significant characteristics that unify them into the taxon Achelata. Its body is remarkably thin, flat, and transparent, with long legs. The phyllosoma larva of spiny lobsters has a long planktonic life before metamorphosing into the puerulus stage, which is the transitional stage from planktonic to a benthic existence. Despite the importance of larval survival to predict recruitment, not much is known about the biology of phyllosoma larvae. In many cases even natural diet is still unclear. Revealing the natural diet of the phyllosoma larvae of spiny lobster. Bull. Fish. Res. Agen. No. 20, 9-13 (review) [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales. Marine plankton include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. Freshwater plankton are similar to marine plankton, but are found in the freshwaters of lakes and rivers. Plankton are usually thought of as inhabiting water, but there are also airborne versions, the aeroplankton, that live part of their lives drifting in the atmosphere. These include plant spores, pollen and wind-scattered seeds, as well as microorganisms swept into the air from terrestrial dust storms and oceanic plankton swept into the air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caulerpa Racemosa
''Caulerpa racemosa'' is a species of edible green alga, a seaweed in the family Caulerpaceae. It is commonly known as sea grapes (along with the related ''Caulerpa lentillifera'') and is found in many areas of shallow sea around the world. There are a number of different forms and varieties, and one that appeared in the Mediterranean Sea in 1990, which is giving cause for concern as an invasive species. Taxonomy There are about 75 species of ''Caulerpa''. Many of them exhibit polymorphism, showing different growth forms in different habitats which makes them difficult to identify. ''C. racemosa'', ''C. laetevirens'' and ''C. peltata'' form a species complex. A number of forms and varieties for ''C. racemosa'' are listed but further study is needed to clarify their exact phylogenetic relationships. Description A plant of ''C. racemosa'' consists of a number of branches linked to stolons which are anchored to the sandy substrate by rhizoids. The branches are a few centimetres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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