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Pseudicius Sengwaensis
''Pseudicius sengwaensis'' is a species of jumping spider in the genus ''Pseudicius'' that lives in Zimbabwe. It is found in the Sengwa Wildlife Research Area, after which it is named. The spider was first described in 2011 by Wanda Wesołowska and Meg Cumming. The female has not been identified. The species is very similar to '' Afraflacilla venustula'', including the pattern on the abdomen. It is a small spider, with a cephalothorax that is typically long and an abdomen typically long. It can be most easily distinguished from other members of the genus by its copulatory organs. The palpal bulb has a distinctive irregular shape, as is the embolus base. Taxonomy ''Pseudicius sengwaensis'' is a jumping spider that was first described by Wanda Wesołowska and Meg Cumming in 2011. They allocated the species to the genus ''Pseudicius'', first raised by Eugène Simon in 1885. The genus name is related to two Greek words that can be translated false and honest. The genus was provis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can reproduction, produce Fertility, fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marchena
''Marchena'' is a genus of jumping spiders only found in the United States. Its only described species, ''M. minuta'', dwells on the barks of conifers along the west coast, especially California, Washington and Nevada.Maddison, Wayne. 1995. Marchena. Marchena minuta. Version 1 January 1995 (under construction). http://tolweb.org/Marchena_minuta/2986/1995.01.01 in The Tree of Life Web Project, http://tolweb.org/ It forms a monophyletic group with the genera '' Afraflacilla'', '' Pseudicius'' and ''Festucula''.Zabka & Grey 2002 Description This species can easily be distinguished from others in its range by the tubercles on the first femur of its first legs. ''M. minuta'' has a body length of about 4 mm. Name The genus name is probably derived from the Spanish city of Marchena, Seville. As witnessed by other generic names, the describers had a habit of naming taxa after places unrelated to the species' distribution. The species name is Latin for "small, minute". No ... [...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, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod Leg
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, plural ''coxae''), ''trochanter'', ''femur'' (plural ''femora''), ''tibia'' (plural ''tibiae''), ''tarsus'' (plural ''tarsi''), ''ischium'' (plural ''ischia''), ''metatarsus'', ''carpus'', ''dactylus'' (meaning finger), ''patella'' (plural ''patellae''). Homologies of leg segments between groups are difficult to prove and are the source of much argument. Some authors posit up to eleven segments per leg for the most recent common ancestor of extant arthropods but modern arthropods have eight or fewer. It has been argued that the ancestral leg need not have been so complex, and that other events, such as successive loss of function of a ''Hox''-gene, could result in parallel gains of leg segments. In arthropods, each of the leg segments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinneret
A spinneret is a silk-spinning organ of a spider or the larva of an insect. Some adult insects also have spinnerets, such as those borne on the forelegs of Embioptera. Spinnerets are usually on the underside of a spider's opisthosoma, and are typically segmented. While most spiders have six spinnerets, some have two, four, or eight. They can move both independently and in concert. Most spinnerets are not simple structures with a single orifice producing a single thread, but complex structures of many microscopic spigots, each producing one filament. This produces the necessary orientation of the protein molecules, without which the silk would be weak and useless. Spigots can be singular or found in groups, which also permits spiders to combine multiple filaments in different ways to produce many kinds of silk for various purposes. Spinneret morphology can help arachnologists identify the taxon of a specimen and the specific morphology of a spigot can determine its use as well ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sternum (arthropod Anatomy)
The sternum (pl. "sterna") is the ventral portion of a segment of an arthropod thorax or abdomen. In insects, the sterna are usually single, large sclerites, and external. However, they can sometimes be divided in two or more, in which case the subunits are called sternites, and may also be modified on the terminal abdominal segments so as to form part of the functional genitalia, in which case they are frequently reduced in size and development, and may become internalized and/or membranous. For a detailed explanation of the terminology, see Kinorhynchs have tergal and sternal plates too, though seemingly not homologous with those of arthropods.Sørensen, M. V. et al. Phylogeny of Kinorhyncha based on morphology and two molecular loci. PLoS One 10, 1–33 (2015). Ventrites are externally visible sternites. Usually the first sternite is covered up, so that vertrite numbers do not correspond to sternid numbers. The term is also used in other arthropod groups such as crustacea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labium (arthropod Mouthpart)
The mouthparts of arthropods have evolved into a number of forms, each adapted to a different style or mode of feeding. Most mouthparts represent modified, paired appendages, which in ancestral forms would have appeared more like legs than mouthparts. In general, arthropods have mouthparts for cutting, chewing, piercing, sucking, shredding, siphoning, and filtering. This article outlines the basic elements of four arthropod groups: insects, myriapods, crustaceans and chelicerates. Insects are used as the model, with the novel mouthparts of the other groups introduced in turn. Insects are not, however, the ancestral form of the other arthropods discussed here. Insects Insect mouthparts exhibit a range of forms. The earliest insects had chewing mouthparts. Specialisation includes mouthparts modified for siphoning, piercing, sucking and sponging. These modifications have evolved a number of times. For example, mosquitoes (which are flies) and aphids (which are bugs) both ... [...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] |
Spider Vision
The eyes of spiders vary significantly in their structure, arrangement, and function. They usually have eight, each being a simple eye with a single lens (optics), lens rather than multiple units as in the compound eyes of insects. The specific arrangement and structure of the eyes is one of the features used in the identification and classification of different species, genera, and families. Most Haplogynae, haplogynes have six eyes, although some have eight (Plectreuridae), four (e.g., ''Tetrablemma'') or even two (most Caponiidae). In some cave species, there are no eyes at all (e.g. Stalita taenaria). Sometimes one pair of eyes is better developed than the rest. Several families of hunting spiders, such as jumping spiders and wolf spiders, have fair to excellent vision. The main pair of eyes in jumping spiders even sees in colour. Structure and anatomy Spiders' eyes are Simple eye in invertebrates, simple eyes, or ''ocelli'' (singular ''ocellus''), meaning their eyes have a si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carapace
A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron. Crustaceans In crustaceans, the carapace functions as a protective cover over the cephalothorax (i.e., the fused head and thorax, as distinct from the abdomen behind). Where it projects forward beyond the eyes, this projection is called a rostrum. The carapace is calcified to varying degrees in different crustaceans. Zooplankton within the phylum Crustacea also have a carapace. These include Cladocera, ostracods, and isopods, but isopods only have a developed "cephalic shield" carapace covering the head. Arachnids In arachnids, the carapace is formed by the fusion of prosomal tergites into a single plate which carries the eyes, ocularium, ozopores (a pair of openings of the scent gland of Opilione ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jerzy Prószyński
Jerzy Prószyński (born 1935 in Warsaw) is a Polish arachnologist specializing in systematics of jumping spiders (family Salticidae). He is a graduate of the University of Warsaw, a long-term employee of the Siedlce University of Natural Sciences and Humanities and the Institute of Zoology of the Polish Academy of Sciences in Warsaw. Biography In 1957 he completed his biological studies at the University of Warsaw. During his studies he was employed at the Institute of Zoology of the Polish Academy of Sciences in Warsaw, where he conducted research on spiders in the Kampinos Forest. Between 1963 and 1967 he lectured on zoology at the University of Ghana. In 1966 he obtained his Ph.D. at the Adam Mickiewicz University in Poznań. A year later he was given the opportunity to pursue a postdoctoral fellowship at Harvard University, but he was refused a passport. In 1972 he was employed at the Higher School of Education in Siedlce (later the Siedlce University of Natural Scie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salticoida
Salticoida is an unranked clade of the jumping spider family Salticidae. It is the larger and more widespread of the two subdivisions of the "typical" jumping spiders (subfamily Salticinae), occurring effectively world-wide. Its sister clade is Amycoida, which is also very diverse ecologically but has a mostly South American distribution. Systematics and evolution Salticoida includes the bulk of extant jumping spider diversity, with over 400 genera organized phylogenetically into 18 tribes according to Wayne Maddison's 2015 proposal. The age and origin of the Salticoida are not well determined. Certainly, by the late Paleogene the major lineages were recognizably distinct as indicated by the fossil evidence and molecular phylogeny. Thus, the salticoids presumably originated during or around the PETM or a bit earlier, but no corresponding fossils have been found yet. Their sister lineage, the Amycoida, probably originated by dispersal across the ocean to South America, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
