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Acanthogonatus Birabeni
''Acanthogonatus birabeni'' is a mygalomorph spider of Argentina, named after Max Birabén, an Argentinian arachnologist.Goloboff, Pablo A. "A revision of the South American spiders of the family Nemesiidae (Araneae, Mygalomorphae). Part 1, Species from Peru, Chile, Argentina, and Uruguay. Bulletin of the AMNH; no. 224." (1995). It differs from others in the ''patagonicus'' group by its smaller size and (except for '' A. fuegianus'') by the less developed bulb keels. Description *Male: total length ; cephalothorax length , width ; cephalic region length , width ; medial ocular quadrangle length , width ; labium length , width ; sternum length , width . Its labium possesses no cuspules. A serrula is apparently present as a small patch of denticles. Its posterior sternal sigilla is small, shallow and marginal; its sternum weakly rebordered. Chelicerae: rastellum is formed by long, thin, stiff setae. Cheliceral tumescence is present. Leg I: tibia long and cylindrical, with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mygalomorphae
The Mygalomorphae, or mygalomorphs, are an infraorder of spiders, and comprise one of three major groups of living spiders with over 3000 species, found on all continents except Antarctica. Many members are known as trapdoor spiders due to them forming trapdoors over their burrows. Other prominent groups include Australian funnel web spiders and tarantulas, with the latter accounting for around one third of all mygalomorphs. Description This group of spiders comprises mostly heavy-bodied, stout-legged spiders including tarantulas, Australian funnel-web spiders, mouse spiders, and various families of spiders commonly called trapdoor spiders. Like the " primitive" suborder of spiders Mesothelae, they have two pairs of book lungs, and downward-pointing chelicerae. Because of this, the two groups were once believed to be closely related. Later it was realized that the common ancestors of all spiders had these features (a state known as symplesiomorphy). Following the branching ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tumescence
Tumescence is the quality or state of being tumescent or swollen. Tumescence usually refers to the normal engorgement with blood (vascular congestion) of the erectile tissues, marking sexual excitation, and possible readiness for sexual activity. The tumescent sexual organ in males is the penis and in females is the clitoris and other parts of the genitalia like the vestibular bulbs. Arteries in the penis dilate to increase blood volume. Detumescence is the reversal of this process, by which blood leaves the erectile tissue, returning the erectile tissue to the flaccid state. Something that causes an erection is sometimes referred to as a tumefier (tumefyer) or tumescer. See also *Nocturnal penile tumescence *Swelling (medical) *Nocturnal clitoral tumescence *Erection *Priapism *Nocturnal emission *Sleep sex *Intumescent An intumescent is a substance that swells as a result of heat exposure, leading to an increase in volume and decrease in density. Intumescent materials are typica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pycnothelidae
''Pycnothelidae'' is a family of mygalomorph spiders first described in 1917. It was downgraded to a subfamily of the funnel-web trapdoor spiders in 1985, but returned to family status in 2020. Genera , the World Spider Catalog accepted the following genera: *'' Acanthogonatus'' Karsch, 1880 – South America *''Bayana'' Pérez-Miles, Costa & Montes de Oca, 2014 *''Pionothele ''Pionothele'' is a genus of African mygalomorph spiders in the family Pycnothelidae. It was first described by William Frederick Purcell in 1902. it contains 2 species, found in Namibia and South Africa: '' P. gobabeb'', and '' P. straminea''. ...'' Purcell, 1902 – South Africa, Namibia *'' Pycnothele'' Chamberlin, 1917 – Uruguay, Brazil, Argentina *'' Stanwellia'' Rainbow & Pulleine, 1918 – Australia, New Zealand *'' Stenoterommata'' Holmberg, 1881 – Brazil, Uruguay, Argentina References Mygalomorphae families {{Mygalomorphae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chubut Province
Chubut ( es, Provincia del Chubut, ; cy, Talaith Chubut) is a province in southern Argentina, situated between the 42nd parallel south (the border with Río Negro Province), the 46th parallel south (bordering Santa Cruz Province), the Andes range to the west, and the Atlantic ocean to the east. The province's name derives from the Tehuelche word , meaning "transparent," their description of the Chubut River. The largest city is Comodoro Rivadavia in the south of the province; it has 180,000 inhabitants. The administrative capital is Rawson (40,000). Other important cities are Puerto Madryn, Trelew, Esquel and Sarmiento. Gaiman is a cultural and demographic centre of the region known as ''"Y Wladfa"'' in which Welsh-Argentines are concentrated. Of the 25,000 Welsh speakers in Argentina, 5,000 live in the Chubut region, particularly in the early Welsh settlements of Gaiman, Trelew and Trevelin. History Before the Spaniards arrived in the Americas, nomadic indigenous Tehu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthogonatus Patagonicus
''Acanthogonatus'' is a genus of South American mygalomorph spiders in the family Pycnothelidae. It was first described by Ferdinand Anton Franz Karsch in 1880. Originally placed with the brushed trapdoor spiders, it was transferred to the funnel-web trapdoor spiders in 1985, then to the Pycnothelidae in 2020. Species it contains twenty-nine species, found in Uruguay, Peru, Brazil, Argentina, and Chile: *'' Acanthogonatus alegre'' Goloboff, 1995 – Chile *'' Acanthogonatus birabeni'' Goloboff, 1995 – Argentina *''Acanthogonatus brunneus'' (Nicolet, 1849) – Chile *'' Acanthogonatus campanae'' (Legendre & Calderón, 1984) – Chile *'' Acanthogonatus centralis'' Goloboff, 1995 – Argentina *'' Acanthogonatus chilechico'' Goloboff, 1995 – Chile *''Acanthogonatus confusus'' Goloboff, 1995 – Chile, Argentina *''Acanthogonatus ericae'' Indicatti, Lucas, Ott & Brescovit, 2008 – Brazil *''Acanthogonatus francki'' Karsch, 1880 (type) – Chile *''Acanthogonatus fuegianus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metatarsus
The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the medial side (the side of the great toe): the first, second, third, fourth, and fifth metatarsal (often depicted with Roman numerals). The metatarsals are analogous to the metacarpal bones of the hand. The lengths of the metatarsal bones in humans are, in descending order, second, third, fourth, fifth, and first. Structure The five metatarsals are dorsal convex long bones consisting of a shaft or body, a base (proximally), and a head (distally).Platzer 2004, p. 220 The body is prismoid in form, tapers gradually from the tarsal to the phalangeal extremity, and is curved longitudinally, so as to be concave below, slightly convex above. The base or posterior extremity is wedge-shaped, articulating proximally with the tarsal bones, and by it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spur (zoology)
A spur is an outgrowth of bone covered in a sheath of horn found in various anatomical locations in some animals. Unlike claws or nails, which grow from the tip of the toes, spurs form from other parts of the foot, usually in connection with joints where the toes meet the foot or the foot meets the long bones. Spurs are most commonly found on the hindfeet, though some birds possess spurs at the leading edge of the wings. Anatomy A spur is much like a true horn; it is a bony core attached to the skeleton and has an outer horny layer. Like horns, the spur grows from the base outwards, so the tip is older than the base. Some spurs form as an outgrowth of an existing bone, though most are secondarily formed as dermal bone hinged to the skeleton through a semi-rigid joint. Spurs on the hind-feet do not appear to molt, but the wing spurs of birds are molted once a year along with the wing feathers. Unlike claws, spurs are normally straight or only slightly curved, making them suited ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibia
The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects the knee with the ankle. The tibia is found on the medial side of the leg next to the fibula and closer to the median plane. The tibia is connected to the fibula by the interosseous membrane of leg, forming a type of fibrous joint called a syndesmosis with very little movement. The tibia is named for the flute ''tibia''. It is the second largest bone in the human body, after the femur. The leg bones are the strongest long bones as they support the rest of the body. Structure In human anatomy, the tibia is the second largest bone next to the femur. As in other vertebrates the tibia is one of two bones in the lower leg, the other being the fibula, and is a component of the knee and ankle joints. The ossification or formation of the bone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Setae
In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. They help, for example, earthworms to attach to the surface and prevent backsliding during peristaltic motion. These hairs make it difficult to pull a worm straight from the ground. Setae in oligochaetes (a group including earthworms) are largely composed of chitin. They are classified according to the limb to which they are attached; for instance, notosetae are attached to notopodia; neurosetae to neuropodia. Crustaceans have mechano- and chemosensory setae. Setae are especially present on the mouthparts of crustaceans and can also be found on grooming limbs. In some cases, setae are modified into scale like structures. Setae on the legs of krill and other small crustaceans help them to gather phytoplankton. It captures them and allows ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, the fourth-largest country in the Americas, and the eighth-largest country in the world. It shares the bulk of the Southern Cone with Chile to the west, and is also bordered by Bolivia and Paraguay to the north, Brazil to the northeast, Uruguay and the South Atlantic Ocean to the east, and the Drake Passage to the south. Argentina is a federal state subdivided into twenty-three provinces, and one autonomous city, which is the federal capital and largest city of the nation, Buenos Aires. The provinces and the capital have their own constitutions, but exist under a federal system. Argentina claims sovereignty over the Falkland Islands, South Georgia and the South Sandwich Islands, and a part of Antarctica. The earliest recorded human prese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelicerae
The chelicerae () are the mouthparts of the subphylum Chelicerata, an arthropod group that includes arachnids, horseshoe crabs, and sea spiders. Commonly referred to as "jaws", chelicerae may be shaped as either articulated fangs, or similarly to pincers. Some chelicerae, such as those found on nearly all spiders, are hollow and contain (or are connected to) venom glands, and are used to inject venom into prey or a perceived threat. In ''Pisaurina mira'', also known as the nursery web spider, the chelicerae are utilized to snatch the prey once it becomes within reach, facilitating the "sit-and-wait ambush predator" behavior. Both pseudoscorpions and harvestmen have structures on their chelicerae that are used for grooming (papillae in pseudoscorpions, cheliceral teeth in Opiliones). Types Chelicerae can be divided into three kinds: jackknife chelicerae, scissor chelicerae, and 3-segmented chelate chelicerae. Jackknife chelicerae The jackknife chelicera is subchelate (with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermal Denticle
A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scales, which can also provide effective camouflage through the use of reflection and colouration, as well as possible hydrodynamic advantages. The term ''scale'' derives from the Old French , meaning a shell pod or husk. Scales vary enormously in size, shape, structure, and extent, ranging from strong and rigid armour plates in fishes such as shrimpfishes and boxfishes, to microscopic or absent in fishes such as eels and anglerfishes. The morphology of a scale can be used to identify the species of fish it came from. Scales originated within the jawless ostracoderms, ancestors to all jawed fishes today. Most bony fishes are covered with the cycloid scales of salmon and carp, or the ctenoid scales of perch, or the ganoid scales of sturgeons and gars. Cartilaginous fishes (sharks and rays) are covered with placoid scales. Some species ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
