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Chimerarachne Yingi
''Chimerarachne'' is a genus of extinct arachnids, sometimes considered as spider itself,Dunlop, J. A., Penney, D. & Jekel, D. 2020A summary list of fossil spiders and their relatives In World Spider Catalog. Natural History Museum Bern, online at http://wsc.nmbe.ch, version 20.5 containing a single species ''Chimerarachne yingi''. Fossils of ''Chimerarachne'' were discovered in Burmese amber from Myanmar which dates to the mid-Cretaceous, about 100 million years ago. Its classification is disputed, either belonging to Uraraneida a group otherwise known from the Devonian to Permian, or a separate clade closer to spiders. Since the earliest spider fossils are from the Carboniferous, either answer results in an at least a 170 myr ghost lineage with no fossil record, making it a Lazarus taxon. The size of the animal is quite small, being only in body length, with the tail being about in length. These fossils resemble spiders in having two of their key defining features: spinner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araneida
Araneida is a subgroup of Tetrapulmonata. It was originally defined by Jörg Wunderlich in 2015 as a subgroup of Araneae, including all true spiders, with Wunderlich also including Uraraneida within Araneae., cited in Araneida was redefined by Wunderlich in 2019 to include all modern spiders (Araneae), as well as Chimerarachnida, but excluding Uraraneida. Chimerarachnida and Araneae both possess spinnerets, which are absent in Uraraneida. Uraraneida and Araneida are grouped together in the clade Serikodiastida.Wunderlich, J. 2019What is a spider?Beiträge zur Araneologie 12: 1–32. See also *Araneidae Orb-weaver spiders are members of the spider family Araneidae. They are the most common group of builders of spiral wheel-shaped webs often found in gardens, fields, and forests. The English word "orb" can mean "circular", hence the English name ... References Spiders Arthropod suborders {{spider-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whip Scorpion
Thelyphonida is an arachnid order comprising invertebrates commonly known as whip scorpions or vinegaroons (also spelled vinegarroons and vinegarones). They are often called uropygids in the scientific community based on an alternative name for the order, Uropygi (which may then also include the order Schizomida). The name "whip scorpion" refers to their resemblance to true scorpions and possession of a whiplike tail, and "vinegaroon" refers to their ability when attacked to discharge an offensive, vinegar-smelling liquid, which contains acetic acid. Taxonomy Carl Linnaeus first described a whip scorpion in 1758, although he did not distinguish it from what are now regarded as different kinds of arachnid, calling it ''Phalangium caudatum''. '' Phalangium'' is now used as a name for a genus of harvestmen (Opiliones). In 1802, Pierre André Latreille was the first to use a genus name solely for whip scorpions, namely ''Thelyphonus''. Latreille later explained the name as meaning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araneae
Spiders (order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species diversity among all orders of organisms. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every land habitat. , 50,356 spider species in 132 families have been recorded by taxonomists. However, there has been debate among scientists about how families should be classified, with over 20 different classifications proposed since 1900. Anatomically, spiders (as with all arachnids) differ from other arthropods in that the usual body segments are fused into two tagmata, the cephalothorax or prosoma, and the opisthosoma, or abdomen, and joined by a small, cylindrical pedicel, however, as there is currently neither paleontological nor embryological evidence that spiders ever had a separate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedipalps
Pedipalps (commonly shortened to palps or palpi) are the second pair of appendages of chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicerae ("jaws") and anterior to the first pair of walking legs. Overview Pedipalps are composed of six segments or articles: the coxa, the trochanter, the femur, the short patella, the tibia, and the tarsus. In spiders, the coxae frequently have extensions called maxillae or gnathobases, which function as mouth parts with or without some contribution from the coxae of the anterior legs. The limbs themselves may be simple tactile organs outwardly resembling the legs, as in spiders, or chelate weapons ( pincers) of great size, as in scorpions. The pedipalps of Solifugae are covered in setae, but have not been studied in detail. Comparative studies of pedipalpal morphology may suggest that leg-like pedipalps are primitive in arachnids. At present, the only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature Ecology And Evolution
''Nature Ecology and Evolution'' is an online-only monthly peer-reviewed scientific journal published by Nature Publishing Group covering all aspects of research on ecology and evolutionary biology. It was established in 2017. Its first and current editor-in-chief is Patrick Goymer. According to the ''Journal Citation Reports'', ''Nature Ecology and Evolution'' has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 15.46. References External links * Nature Research academic journals Publications established in 2017 Ecology journals Monthly journals English-language journals {{ecology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palpal Bulb
The two palpal bulbs – also known as palpal organs and genital bulbs – are the copulatory organs of a male spider. They are borne on the last segment of the pedipalps (the front "limbs" of a spider), giving the spider an appearance often described as like wearing boxing gloves. The palpal bulb does not actually produce sperm, being used only to transfer it to the female. Palpal bulbs are only fully developed in adult male spiders and are not completely visible until after the final moult. In the majority of species of spider, the bulbs have complex shapes and are important in identification. Structure The palpal bulb of a mature male spider is borne on the last segment of the pedipalp. This segment usually has touch-sensitive hairs (setae) with nerves leading to them. The bulb itself is entirely without nerves, and hence without sensory organs and muscles, since these depend on nerves for their functioning, although some spiders have one or two muscles external to the bulb and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossary Of Spider Terms
This glossary describes the terms used in formal descriptions of spiders; where applicable these terms are used in describing other arachnids. Links within the glossary are shown . Terms A Abdomen or opisthosoma: One of the two main body parts ( tagmata), located towards the posterior end; see also Abdomen § Other animals Accessory claw: Modified at the tip of the in web-building spiders; used with to grip strands of the web Anal tubercle: A small protuberance (tubercule) above the through which the anus opens Apodeme → Apophysis (plural apophyses): An outgrowth or process changing the general shape of a body part, particularly the appendages; often used in describing the male → Atrium (plural atria): An internal chamber at the entrance to the in female haplogyne spiders B Bidentate: Having two Book lungs: Respiratory organs on the ventral side (underside) of the , in front of the , opening through narrow slits; see also Book lungs Branchial operculum â ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedipalp
Pedipalps (commonly shortened to palps or palpi) are the second pair of appendages of chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicerae ("jaws") and anterior to the first pair of walking legs. Overview Pedipalps are composed of six segments or articles: the coxa, the trochanter, the femur, the short patella, the tibia, and the tarsus. In spiders, the coxae frequently have extensions called maxillae or gnathobases, which function as mouth parts with or without some contribution from the coxae of the anterior legs. The limbs themselves may be simple tactile organs outwardly resembling the legs, as in spiders, or chelate weapons ( pincers) of great size, as in scorpions. The pedipalps of Solifugae are covered in setae, but have not been studied in detail. Comparative studies of pedipalpal morphology may suggest that leg-like pedipalps are primitive in arachnids. At present, the only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mygalomorphs
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 branchin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesothelae
The Mesothelae are a suborder of spiders (order Araneae) that includes a single extant family, Liphistiidae, and a number of extinct families. This suborder is thought to form the sister group to all other living spiders, and to retain ancestral characters, such as a segmented abdomen with spinnerets in the middle and two pairs of book lungs. Members of Liphistiidae are medium to large spiders with eight eyes grouped on a tubercle. They are found only in China, Japan, and southeast Asia. The oldest known Mesothelae spiders are known from the Carboniferous, over 300 million years ago. The Heptathelidae were once considered their own family; today they are considered a subfamily of the Liphistiidae. Description Members of Mesothelae have paraxial chelicerae, two pairs of coxal glands on the legs, eight eyes grouped on a nodule, two pairs of book lungs, and no endites on the base of the pedipalp. Most have at least seven or eight spinnerets near the middle of the abdomen. Lateral ... [...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] |
