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Flat-clawed Hermit Crab
''Pagurus pollicaris'' is a hermit crab commonly found along the Atlantic coast of North America from New Brunswick to the Gulf of Mexico. It is known by a number of common names, including ''gray hermit crab'', ''flat-clawed hermit crab'', ''flatclaw hermit crab'', ''shield hermit crab'', ''thumb-clawed hermit crab'', ''broad-clawed hermit crab'', and ''warty hermit crab''. ''P. pollicaris'' inhabits the shells of shark eye snails and whelks. It grows to a length of and a width of . The shell is often shared by the commensal zebra flatworm (''Stylochus ellipticus''). The diet of the flat-clawed hermit crab comprises organic matter, algae, and sometimes other hermit crabs. Fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ... are the most important predators of this species. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Say
Thomas Say (June 27, 1787 – October 10, 1834) was an American entomologist, conchologist, and Herpetology, herpetologist. His studies of insects and shells, numerous contributions to scientific journals, and scientific expeditions to Florida, Georgia, the Rocky Mountains, Mexico, and elsewhere made him an internationally known naturalist. Say has been called the father of American descriptive entomology and American conchology. He served as librarian for the Academy of Natural Sciences of Philadelphia, curator at the American Philosophical Society (elected in 1817), and professor of natural history at the University of Pennsylvania. Early life and education Born in Philadelphia into a prominent Religious Society of Friends, Quaker family, Thomas Say was the great-grandson of John Bartram, and the great-nephew of William Bartram. His father, Dr. Benjamin Say, was brother-in-law to another Bartram son, Moses Bartram. The Say family had a house, "The Cliffs" at Gray's Ferry Bridge, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portable Document Format
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems.Adobe Systems IncorporatedPDF Reference, Sixth edition, version 1.23 (53 MB) Nov 2006, p. 33. Archiv/ref> Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991. PDF was standardized as ISO 32000 in 2008. The last edition as ISO 32000-2:2020 was published in December 2020. PDF files may contain a variety of content besides flat text and graphics including logical structuring elements, interactive elements such as annotations and form-fields, layers, rich media (including video con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermit Crabs
Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their fragile exoskeletons. There are over 800 species of hermit crab, most of which possess an asymmetric abdomen concealed by a snug-fitting shell. Hermit crabs' soft (non-calcified) abdominal exoskeleton means they must occupy shelter produced by other organisms or risk being defenseless. The strong association between hermit crabs and their shelters has significantly influenced their biology. Almost 800 species carry mobile shelters (most often calcified snail shells); this protective mobility contributes to the diversity and multitude of crustaceans found in almost all marine environments. In most species, development involves metamorphosis from symmetric, free-swimming larvae to morphologically asymmetric, benthic-dwelling, shell-seeking crabs. Such physiological and behavioral extremes facilitate a transition to a sheltered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alga
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as ''Chlorella,'' ''Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and autotrophic (they generate food internally) and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the ''Charophyta'', a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. No definition of algae is generally accepted. One definition is that algae "have chlorophyll ''a'' as their primary photosynthetic pigment and lack a sterile covering of cells around t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylochus Ellipticus
Stylochidae is a family of Polycladida, polyclad flatworms. It includes the species ''Stylochus zebra'', which usually lives in shells occupied by the hermit crab ''Pagurus pollicaris'', though it can sometimes be found free living on rocks and pilings. The family contains the following 6 genera containing 36 accepted species: *''Cryptostylochus'' **''Cryptostylochus coseirensis'' **''Cryptostylochus hullensis'' **''Cryptostylochus koreensis'' *''Distylochus'' **''Distylochus isifer'' **''Distylochus martae'' **''Distylochus pusillus'' *''Kataria gloriosa, Kataria'' **''Kataria gloriosa'' *''Leptostylochus'' **''Leptostylochus capensis'' **''Leptostylochus elongatus'' **''Leptostylochus gracilis'' **''Leptostylochus novacambrensis'' **''Leptostylochus pacificus'' **''Leptostylochus palombii'' **''Leptostylochus polysorus'' *''Stylochopsis'' **''Stylochopsis ellipticus'' **''Stylochopsis ponticus'' *''Stylochus'' **''Stylochus alexandrinus'' **''Stylochus argus'' **''Stylochus ber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commensalism
Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit from each other; amensalism, where one is harmed while the other is unaffected; parasitism, where one is harmed and the other benefits, and parasitoidism, which is similar to parasitism but the parasitoid has a free-living state and instead of just harming its host, it eventually ends up killing it. The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the host organism is unmodified, whereas the commensal species may show great structural adaptation consistent with its habits, as in the remoras that ride attached to sharks and other fishes. Remo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whelk
Whelk (also known as scungilli) is a common name applied to various kinds of sea snail. Although a number of whelks are relatively large and are in the family Buccinidae (the true whelks), the word ''whelk'' is also applied to some other marine gastropod species within several families of sea snails that are not very closely related. Many have historically been used, or are still used, by humans and other animals as food. In a reference serving of whelk, there are of food energy, 24 g of protein, 0.34 g of fat, and 8 g of carbohydrates. Dogwinkles, a predatory species, were used in antiquity to make a rich red dye that improves in color as it ages. True whelks are carnivorous, and feed on annelids, crustaceans, mussels and other molluscs, drilling holes through shells to gain access to the soft tissues. Whelks use chemoreceptors to locate their prey. Usage The common name "whelk" is also spelled ''welk'' or even ''wilk''. The species, genera and families re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark Eye
''Neverita duplicata'', common name the shark eye, is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails. In 2006, a paper was published which made it clear that a second, very similar, species with a smaller range of distribution also lives in part of the range inhabited by ''Neverita duplicata''. The second species had previously been considered to be simply a form of ''N. duplicata'', but it is now recognized as ''Neverita delessertiana''.Huelsken, T. ''et al.'' (2006) ''Neverita delessertiana'' (Recluz in Chenu, 1843): a naticid species (Gastropoda: Caenogastropoda) distinct from ''Neverita duplicata'' (Say, 1822) based on molecular data, morphological characters, and geographical distribution. ''Zootaxa'', 1-25PDF Distribution This is a common western Atlantic species. It is found from Massachusetts and other parts of New England, south to Florida and other states on the Gulf of Mexico, south to Honduras. Description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropod Shell
The gastropod shell is part of the body of a Gastropoda, gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or in some cases the shell is reduced such that the body cannot be retracted within it (semi-slug). Some snails also possess an operculum that seals the opening of the shell, known as the Aperture (mollusc), aperture, which provides further protection. The study of mollusc shells is known as conchology. The biological study of gastropods, and other molluscs in general, is malacology. Shell morphology terms vary by species group. Shell layers The gastropod shell has three major layers secreted by the Mantle (mollusc), mantle. The calcareous central layer, tracum, is typically made of calcium carbonate precipitated into an organic matrix known as c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bulletin Of The Bureau Of Fisheries
The ''Fishery Bulletin'' is a quarterly peer-reviewed scientific journal published by the National Oceanic and Atmospheric Administration. It was established in 1881 and was until 1903 published as the ''Bulletin of the United States Fish Commission'' by the United States Fish Commission. The journal then went through a number of changes in its name: ''Bulletin of the Bureau of Fisheries'' (1904–1911), ''Bulletin of the United States Fish Commission'' (1912–1940), ''Fishery Bulletin of the Fish and Wildlife Service'' (1941–1970), and finally from 1971, ''Fishery Bulletin''. All content has been scanned and is available through the journal's page or the site maintained by the NOAA Central library. Its editorial board is headed by biologist Jose I. Castro, editor Kathryn Dennis and communicologist Cara Mayo. Currently, it also includes renowned researchers such as Henry L. Bart Jr, Katherine E. Bemis, Matthew D. Campbell, William B. Driggers III, Gretchen L. Grammer, Richard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermit Crab
Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their fragile exoskeletons. There are over 800 species of hermit crab, most of which possess an asymmetric abdomen concealed by a snug-fitting shell. Hermit crabs' soft (non-calcified) abdominal exoskeleton means they must occupy shelter produced by other organisms or risk being defenseless. The strong association between hermit crabs and their shelters has significantly influenced their biology. Almost 800 species carry mobile shelters (most often calcified snail shells); this protective mobility contributes to the diversity and multitude of crustaceans found in almost all marine environments. In most species, development involves metamorphosis from symmetric, free-swimming larvae to morphologically asymmetric, benthic-dwelling, shell-seeking crabs. Such physiological and behavioral extremes facilitate a transition to a sheltered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
