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Rugathodes Sexpunctatus
''Rugathodes sexpunctatus'' is a minute species of spider in the family Theridiidae, the cobweb or tangle-web spiders. This family includes the medically important genus '' Latrodectus''—the widow spiders. The species in the genus ''Rugathodes'' are too small to be dangerous to humans. Very little is known about most species in this genus. Description Total length (of body, excluding legs) is 1.5-2.5 mm. Typically, the cephalothorax is pale yellow-brown with a dark/blackish median band, usually extending the full length of the carapace, widest at the posterior eye row, surrounding the eyes. The cephalothorax margins are dusky. The abdomen is pale yellow-brown with a variable pattern of three pairs of black and white spots, giving the species its name (from the Latin sex meaning "six" and punctum meaning "spot"). There is often a broken white band bordering the rows of spots. The sides of the abdomen are dusky and the ventral surface is pale. There is considerable variat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Henry Emerton
James Henry Emerton (March 31, 1847 – December 5, 1931) was an American arachnologist and illustrator. Early life Emerton was born at Salem, Massachusetts, on March 31, 1847. He was rather frail, and a young helper in his father's drug store, George F. Markoe, interested the boy in outdoor life. They collected plants, insects and shore invertebrates and at the age of fifteen he was frequently visiting the Essex Institute, where he became acquainted with A. S. Packard, F. W. Putnam, John Robinson, Caleb Cooke, and others who later became more or less prominent students of natural history. From the first, he showed much skill in drawing and made sketches of a great variety of natural objects. Of these early drawings, there are many in Packard's ''Guide'' and forty quarto plates in Watson and Eaton ''Botany of the Fortieth Parallel'' published in 1871. Professional life He was elected to the Boston Society of Natural History in 1870, and later, 1873-1874 was an assistant in the M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theridiidae
Theridiidae, also known as the tangle-web spiders, cobweb spiders and comb-footed spiders, is a large family of Araneomorphae, araneomorph spiders first described by Carl Jakob Sundevall in 1833. This diverse, globally distributed family includes over 3,000 species in 124 genus, genera, and is the most common arthropod found in human dwellings throughout the world. Theridiid spiders are both Entelegynae, entelegyne, meaning that the females have a genital plate, and Cribellum, ecribellate, meaning that they spin sticky capture silk instead of woolly silk. They have a comb of serrated bristles (setae) on the Arthropod leg, tarsus of the fourth leg. The family includes some model organisms for research, including the List of medically significant spider bites, medically important Latrodectus, widow spiders. They are important to studies characterizing their venom and its clinical manifestation, but widow spiders are also used in research on spider silk and sexual biology, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latrodectus
''Latrodectus'' is a broadly distributed genus of spiders with several species that are commonly known as the true widows. This group is composed of those often loosely called black widow spiders, brown widow spiders, and similar spiders. However, the diversity of species is much greater. A member of the family Theridiidae, this genus contains 34 species, which include several North American "black widows" (southern black widow '' Latrodectus mactans'', western black widow '' Latrodectus hesperus'', and northern black widow '' Latrodectus variolus''). Besides these, North America also has the red widow '' Latrodectus bishopi'' and the brown widow '' Latrodectus geometricus'', which, in addition to North America, has a much wider geographic distribution. Elsewhere, others include the European black widow (''Latrodectus tredecimguttatus''), the Australian redback black widow (''Latrodectus hasseltii'') and the closely related New Zealand katipō (''Latrodectus katipo''), several ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rugathodes SexpunctatusFemaleEggCaseParasite
''Rugathodes'' is a genus of comb-footed spiders that was first described by Allan Frost Archer in 1950. It is closely related to members of ''Theridion'' and '' Wamba''. Species it contains eight species with a mostly paleotropical distribution: *''Rugathodes acoreensis'' Wunderlich, 1992 – Azores *''Rugathodes aurantius'' (Emerton, 1915) – North America, Russia (Europe to Far East), Kazakhstan *''Rugathodes bellicosus'' (Simon, 1873) – Europe, Russia (Europe to South Siberia) *''Rugathodes instabilis'' ( O. Pickard-Cambridge, 1871) – Europe, Russia (Europe to West Siberia) *''Rugathodes madeirensis'' Wunderlich, 1987 – Madeira *''Rugathodes nigrolimbatus'' (Yaginuma, 1972) – Japan *''Rugathodes pico'' (Merrett & Ashmole, 1989) – Azores *''Rugathodes sexpunctatus'' (Emerton, 1882) (type) – USA, Canada, Russia (Commander Is.). Introduced to Britain In synonymy: *''R. lowriei'' (Barrows, 1945) = ''Rugathodes aurantius'' (Emerton, 1915) See also * List of Therid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalothorax
The cephalothorax, also called prosoma in some groups, is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. (The terms ''prosoma'' and ''opisthosoma'' are equivalent to ''cephalothorax'' and ''abdomen'' in some groups.) The word ''cephalothorax'' is derived from the Greek words for head (, ') and thorax (, '). This fusion of the head and thorax is seen in chelicerates and crustaceans; in other groups, such as the Hexapoda (including insects), the head remains free of the thorax. In horseshoe crabs and many crustaceans, a hard shell called the carapace covers the cephalothorax. Arachnid anatomy Fovea The fovea is the centre of the cephalothorax and is located behind the head (only in spiders).Dalton, Steve (2008). ''Spiders; The Ultimate Predators''. A & C Black, London. P.p. 19. . It is often important in identification. It can be transverse or procurved Smith, A. M. (1990c). Baboon spiders: Tarantulas of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abdomen
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. The area occupied by the abdomen is called the abdominal cavity. In arthropods it is the posterior tagma of the body; it follows the thorax or cephalothorax. In humans, the abdomen stretches from the thorax at the thoracic diaphragm to the pelvis at the pelvic brim. The pelvic brim stretches from the lumbosacral joint (the intervertebral disc between L5 and S1) to the pubic symphysis and is the edge of the pelvic inlet. The space above this inlet and under the thoracic diaphragm is termed the abdominal cavity. The boundary of the abdominal cavity is the abdominal wall in the front and the peritoneal surface at the rear. In vertebrates, the abdomen is a large body cavity enclosed by the abdominal muscles, at front and to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R Sexpunctatus Epigynum
R, or r, is the eighteenth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''ar'' (pronounced ), plural ''ars'', or in Ireland ''or'' . The letter is the eighth most common letter in English and the fourth-most common consonant (after , , and ). The letter is used to form the ending "-re", which is used in certain words such as ''centre'' in some varieties of English spelling, such as British English. Canadian English also uses the "-re" ending, unlike American English, where the ending is usually replaced by "-er" (''center''). This does not affect pronunciation. Name The name of the letter in Latin was (), following the pattern of other letters representing continuants, such as F, L, M, N and S. This name is preserved in French and many other languages. In Middle English, the name of the letter changed from to , following a pattern exhibited in many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epigyne
The epigyne or epigynum is the external genital structure of female spiders. As the epigyne varies greatly in form in different species, even in closely related ones, it often provides the most distinctive characteristic for recognizing species. It consists of a small, hardened portion of the exoskeleton located on the underside of the abdomen, in front of the epigastric furrow and between the epigastric plates. Functions The primary function of the epigyne is to receive and direct the palpal organ of the male during copulation. The various specific forms of epigynes are correlated, in each case, with corresponding specific differences in the palpus of the male. This specialization prevents individuals of different species from mating. The epigyne covers or accompanies the openings of the spermathecae, which are pouches for receiving and retaining sperm. Frequently, the openings of the spermathecae are on the outer face of the epigyne and can be easily seen. A secondary funct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rugathodes Sexpunctatus Chelicera
''Rugathodes'' is a genus of comb-footed spiders that was first described by Allan Frost Archer in 1950. It is closely related to members of ''Theridion'' and '' Wamba''. Species it contains eight species with a mostly paleotropical distribution: *''Rugathodes acoreensis'' Wunderlich, 1992 – Azores *''Rugathodes aurantius'' (Emerton, 1915) – North America, Russia (Europe to Far East), Kazakhstan *''Rugathodes bellicosus'' (Simon, 1873) – Europe, Russia (Europe to South Siberia) *''Rugathodes instabilis'' ( O. Pickard-Cambridge, 1871) – Europe, Russia (Europe to West Siberia) *''Rugathodes madeirensis'' Wunderlich, 1987 – Madeira *''Rugathodes nigrolimbatus'' (Yaginuma, 1972) – Japan *''Rugathodes pico'' (Merrett & Ashmole, 1989) – Azores *''Rugathodes sexpunctatus'' (Emerton, 1882) (type) – USA, Canada, Russia (Commander Is.). Introduced to Britain In synonymy: *''R. lowriei'' (Barrows, 1945) = ''Rugathodes aurantius'' (Emerton, 1915) See also * List of Therid ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instars
An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or assume a new form. Differences between instars can often be seen in altered body proportions, colors, patterns, changes in the number of body segments or head width. After shedding their exoskeleton (moulting), the juvenile arthropods continue in their life cycle until they either pupate or moult again. The instar period of growth is fixed; however, in some insects, like the salvinia stem-borer moth, the number of instars depends on early larval nutrition. Some arthropods can continue to moult after sexual maturity, but the stages between these subsequent moults are generally not called instars. For most insect species, an ''instar'' is the developmental stage of the larval forms of holometabolous (complete metamorphism) or nymphal forms o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
