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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] |
Cheiracanthium Mildei Male
''Cheiracanthium'', commonly called yellow sac spiders, is a genus of Araneomorphae, araneomorph spiders in the family Cheiracanthiidae, and was first described by Carl Ludwig Koch in 1839. They are usually pale in colour, and have an spider anatomy#Abdomen, abdomen that can range from yellow to beige. Both sexes range in size from . They are unique among common house spiders because their tarsus (arthropod), tarsi do not point either outward, like members of ''Tegenaria'', or inward, like members of ''Araneus'', making them easier to identify. Venom Though they are beneficial predators in agricultural fields, they are also known to be mildly venomous to humans. Painful bites may be incurred from species such as ''Cheiracanthium punctorium, C. punctorium'' in Europe, ''Cheiracanthium mildei, C. mildei'' in Europe and North America, ''Cheiracanthium inclusum, C. inclusum'' in the Americas, ''C. lawrencei'' in South Africa and ''C. japonicum'' in Japan. ''Cheiracanthium'' venom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptathela
''Heptathela'' is a genus of spiders that includes the Kimura spider (''Heptathela kimurai''). They are trapdoor spiders of the family Heptathelidae and are found in Japan, including Okinawa and the Ryukyu Islands. Spiders of this genus lack venom glands. Full text at (60 MB) Females are up to 25 mm long, males slightly smaller. Burrows have an oval shaped door which is hinged across the long diameter. Name The genus name is derived from Ancient Greek ''hepta'' "seven", referring to the number of spinneret glands. Species , the World Spider Catalog accepted the following species: *'' Heptathela aha'' Xu, Ono, Kuntner, Liu & Li, 2019 – Ryukyu Is. *'' Heptathela amamiensis'' Haupt, 1983 – Ryukyu Is. *'' Heptathela crypta'' Xu, Ono, Kuntner, Liu & Li, 2019 – Ryukyu Is. *'' Heptathela gayozan'' Xu, Ono, Kuntner, Liu & Li, 2019 – Ryukyu Is. *'' Heptathela helios'' Tanikawa & Miyashita, 2014 (synonym ''H. yaginumai'' Ono, 1998) – Japan *'' Heptathela higoensis' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unicorn Catleyi Copulatory Bulb
The unicorn is a legendary creature that has been described since Classical antiquity, antiquity as a beast with a single large, pointed, spiraling horn (anatomy), horn projecting from its forehead. In European literature and art, the unicorn has for the last thousand years or so been depicted as a white horse- or goat-like animal with a long straight horn with spiraling grooves, cloven hooves, and sometimes a goat's beard. In the Middle Ages and Renaissance, it was commonly described as an extremely wild forest, woodland creature, a symbol of purity and grace, which could be captured only by a virgin. In encyclopedias, its horn was described as having the power to render poisoned water potable and to heal sickness. In medieval and Renaissance times, the tusk of the narwhal was sometimes sold as a unicorn horn. A bovine type of unicorn is thought by some scholars to have been depicted in Indus seal, seals of the Bronze Age Indus Valley Civilisation, Indus Valley civilization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomisus Spectabilis
''Thomisus spectabilis'', also known as the white crab spider or Australian crab spider, is a small spider found in Australia and far east Asia. The body length of the female is up to 10 mm, the male 6.2 mm. Including legs, the spider is around 3 cm across.Australian Spiders in Colour - Ramon Mascord 1970 SBN 589 07065 7, page 48 This spider is usually white, though sometimes may appear yellow. The legs and head appear almost translucent. ''Thomisus spectabilis'' is an ambush predator, often seen resting in flowers of its same color. Its egg sacs are laid in a folded leaf, and the cream colored eggs, typically 1 mm in diameter, range between 200 and 370 in number. These spiders primarily eat insects and their preference for symmetry helps them in capturing pollinating insects such as butterflies and bees.Astrid M. Heiling, Ken Cheng, Marie E. Herberstein, Exploitation of floral signals by crab spiders (''Thomisus spectabilis'', Thomisidae), ''Behavioral Ec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogynae
The Haplogynae or haplogynes are one of the two main groups into which araneomorph spiders have traditionally been divided, the other being the Entelegynae. Morphological phylogenetic studies suggested that the Haplogynae formed a clade; more recent molecular phylogenetic studies refute this, although many of the ecribellate haplogynes do appear to form a clade, Synspermiata. Unlike the Entelegynae, haplogynes lack hardened (sclerotized) female genitalia ( epigynes). Most of the species within this group have six eyes, as opposed to most other spiders. Spiders in the genus '' Tetrablemma'' ( Tetrablemmidae) have only four eyes, as do some members of the family Caponiidae; caponiids may even have only two eyes. However, spiders in the family Plectreuridae have the normal eight eyes. Phylogeny The Haplogynae are one of the two major groups into which araneomorph spiders were traditionally divided, the other being the Entelegynae. In 2005, Coddington summarized the relatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araneus
''Araneus'' is a genus of common orb-weaving spiders. It includes about 650 species, among which are the European garden spider and the barn spider. The genus was erected by Carl Alexander Clerck in 1757. Description Spiders of this genus present perhaps the most obvious case of sexual dimorphism among all of the orb-weaver family, with males being normally to the size of females. In ''A. diadematus'', for example, last-molt females can reach the body size up to 1 in (2.5 cm), while most males seldom grow over 0.3 in (1 cm), both excluding leg span. Males are differentiated from females by a much smaller and more elongated abdomen, longer legs, and the inability to catch or consume prey bigger than themselves. In females, the epigyne has a long scape (a tongue-like appendage). Male pedipalps have a hook-like terminal Tubercle (anatomy), apophysis. Abdominal tubercle (anatomy), tubercles are present anterolaterally. Taxonomic history ''Araneus'' was, for m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agelenopsis
''Agelenopsis'', commonly known as the American grass spiders, is a genus of funnel weavers described by C.G. Giebel in 1869. They weave sheet webs that have a funnel shelter on one edge. The web is not sticky, but these spiders make up for that by running very rapidly. The larger specimens (depending on species) can grow to about 19 mm in body length. They may be recognized by the arrangement of their eight eyes into three rows. The top row has two eyes, the middle row has four eyes, and the bottom row has two eyes (spaced wider than the ones on the top row). They have two prominent hind spinnerets, somewhat indistinct bands on their legs, and two dark bands running down either side of the cephalothorax. Name The genus name is a combination of '' Agelena'' (Eurasian grass spiders), a genus of similar spiders, and Greek ''-opsis'' "to look like". They are harmless spiders. Although most spiders use their webs to catch prey, the grass spider's web lacks adhesive ability. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithelium
Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of many internal organs, the corresponding inner surfaces of body cavities, and the inner surfaces of blood vessels. Epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. These tissues also lack blood or lymph supply. The tissue is supplied by nerves. There are three principal shapes of epithelial cell: squamous (scaly), columnar, and cuboidal. These can be arranged in a singular layer of cells as simple epithelium, either simple squamous, simple columnar, or simple cuboidal, or in layers of two or more cells deep as stratified (layered), or ''compound'', either squamous, columnar or cuboidal. In some tissues, a layer of columnar cells may appear to be stratified d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonopore
A gonopore, sometimes called a gonadopore, is a genital pore in many invertebrates. Hexapods, including insects, have a single common gonopore, except mayflies, which have a pair of gonopores. More specifically, in the unmodified female, it is the opening of the common oviduct, and in the male, it is the opening of the ejaculatory duct. The position of the gonopore varies considerably between groups, but is generally constant within groups, allowing its position to be used as a "segmental marker". In Malacostraca, it is on the sixth thoracic segment; in Symphyla, it is on the fourth trunk segment; in arachnids, it is on the second segment of the opisthosoma. In insects and centipedes, the gonopores are close to the animal's tail, while in millipede Millipedes (originating from the Latin , "thousand", and , "foot") are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Dipl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abdomen
The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal cavity. In arthropods, it is the posterior (anatomy), posterior tagma (biology), 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 Lumbar vertebrae, L5 and Vertebra#Sacrum, 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 the front an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testes
A testicle or testis ( testes) is the gonad in all male bilaterians, including humans, and is homologous to the ovary in females. Its primary functions are the production of sperm and the secretion of androgens, primarily testosterone. The release of testosterone is regulated by luteinizing hormone (LH) from the anterior pituitary gland. Sperm production is controlled by follicle-stimulating hormone (FSH) from the anterior pituitary gland and by testosterone produced within the gonads. Structure Appearance Males have two testicles of similar size contained within the scrotum, which is an extension of the abdominal wall. Scrotal asymmetry, in which one testicle extends farther down into the scrotum than the other, is common. This is because of the differences in the vasculature's anatomy. For 85% of men, the right testis hangs lower than the left one. Measurement and volume The volume of the testicle can be estimated by palpating it and comparing it to ellipsoids (an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachnid
Arachnids are arthropods in the Class (biology), class Arachnida () of the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, opiliones, harvestmen, Solifugae, camel spiders, Amblypygi, whip spiders and Uropygi, vinegaroons. Adult arachnids have eight Arthropod leg, legs attached to the cephalothorax. In some species the frontmost pair of legs has converted to a sensory function, while in others, different appendages can grow large enough to take on the appearance of extra pairs of legs. Almost all Extant taxon, extant arachnids are terrestrial animal, terrestrial, living mainly on land. However, some inhabit freshwater environments and, with the exception of the pelagic zone, marine environments as well. They comprise over 110,000 named species, of which 51,000 are species of spiders. The term is derived from the Ancient Greek, Greek word (''aráchnē'', 'spider'), from the myth of the hubristic human weaver Arachne, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
