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Harvestman
The Opiliones (formerly Phalangida) are an order of arachnids colloquially known as harvestmen, harvesters, harvest spiders, or daddy longlegs. , over 6,650 species of harvestmen have been discovered worldwide, although the total number of extant species may exceed 10,000. The order Opiliones includes five suborders: Cyphophthalmi, Eupnoi, Dyspnoi, Laniatores, and Tetrophthalmi, which were named in 2014. Representatives of each extant suborder can be found on all continents except Antarctica. Well-preserved fossils have been found in the 400-million-year-old Rhynie cherts of Scotland, and 305-million-year-old rocks in France. These fossils look surprisingly modern, indicating that their basic body shape developed very early on, and, at least in some taxa, has changed little since that time. Their phylogenetic position within the Arachnida is disputed; their closest relatives may be the mites ( Acari) or the Novogenuata (the Scorpiones, Pseudoscorpiones, and Solifuga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyspnoi
Dyspnoi is a suborder of harvestmen, currently comprising 43 extant genera and 356 extant species, although more species are expected to be described in the future. The eight families are currently grouped into three superfamilies: the Acropsopilionoidea, Ischyropsalidioidea, and Troguloidea. Distribution The Dyspnoi are one of the most biogeographically conserved higher groups of harvestmen. With the exception of Acropsopilioidea, none occur in the Southern Hemisphere, and most families are restricted along temperate regions. The only exceptions are some Ortholasmatinae (Nemastomatidae) inhabiting the tropics on high mountains in Mexico ('' Ortholasma bolivari'') and northern Thailand ('' Dendrolasma angka''). Systematics * Acropsopilionoidea ** Acropsopilionidae (3 genera, 19 species) * Ischyropsalidoidea **Ischyropsalidoidea ''Incertae sedis'' ***'' Crosbycus dasycnemus'' ***''Hesperonemastoma'' (5 species) **Ischyropsalididae *** Ceratolasmatinae (2 genera, 8 species) *** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hadrobunus Grandis
''Hadrobunus grandis'' is a species of harvestman that occurs in the United States (Georgia, Maryland, North Carolina, Ohio, Indiana, Oklahoma, and Virginia Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the East Coast of the United States, Atlantic Coast and the Appalachian Mountains. The geography an ...). Adults can be found in early summer. Their backs are brown, with a central marking that can be absent. The legs have a banded appearance. The species is similar to '' H. maculosus'', but the latter has no spines on its back and is darker. References The Harvestmen of Maryland Further reading * (1924): Notes on the Opiliones of the southeastern United States with descriptions of new species. ''J. Elisha Mitchell Sci. Soc.'' 40: 8-26. Harvestmen Arthropods of the United States Animals described in 1821 {{Opiliones-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyphophthalmi
Cyphophthalmi is a suborder of harvestmen, colloquially known as mite harvestmen. Cyphophthalmi comprises 36 genera, and more than two hundred described species. The six families are currently grouped into three infraorders: the Boreophthalmi, Scopulophthalmi, and Sternophthalmi. Description Cyphophthalmi are smaller than the more familiar "daddy long-legs" harvestmen, with adults ranging from 1 to 7 mm in length. Moreover, their legs are relatively short compared to most other harvestmen, typically shorter than the body. Some superficially resemble mites, which is where they get their common name. Their coloration is almost always some shade of brown, with a heavily sclerotized body, and they are quite inconspicuous, residing in leaf litter or in caves. Many Cyphophthalmi are eyeless, and presumably rely on olfactory cues to find food and mates. Very little is known about their behavior, though they likely subsist mostly by scavenging and preying on minute arthropods. They ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eupnoi
The Eupnoi are a suborder of harvestmen, with more than 200 genera, and about 1,700 described species. They consist of two superfamilies, the Phalangioidea with many long-legged species common to northern temperate regions, and the small group Caddoidea, which have prominent eyes and spiny pedipalps. (2007): Morphology and Functional Anatomy. In: Pinto-da-Rocha ''et al.'' 2007: 17f Examples of this suborder include '' Hadrobunus grandis'' (Sclerosomatidae), ''Phalangium opilio'' and '' Dicranopalpus ramosus'' (Phalangiidae). Distribution Caddoidea are mostly found in temperate zones of both hemispheres; however, they are known from the Palearctic only from Japan, and from Baltic amber (about 40 million years old). One species known from Japan is also found in North America, where several more species are found. Other species occur in Southern South America, Venezuela, New Zealand and Australia. Neopilionidae show a Gondwanan distribution, with species found in South Ameri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhynie Chert
The Rhynie chert is a Lower Devonian sedimentary deposit exhibiting extraordinary fossil detail or completeness (a Lagerstätte). It is exposed near the village of Rhynie, Aberdeenshire, Scotland; a second unit, the Windyfield chert, is located some 700 m away. The Rhynie chert contains exceptionally preserved plant, fungus, lichen and animal material preserved in place by an overlying volcanic deposit. The bulk of the Devonian fossil bed consists of primitive plants (which had water-conducting cells and sporangia, but no true leaves), along with arthropods, lichens, algae and fungi. This fossil bed is remarkable for two reasons. First, the age of the site (Pragian, Early Devonian, formed about ) places it at an early stage in the colonisation of land. Second, these cherts are famous for their exceptional state of ultrastructural preservation, with individual cell walls easily visible in polished specimens. Stomata have been counted and lignin remnants detected in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pholcidae
The Pholcidae are a family of araneomorph spiders. The family contains over 1,800 individual species of pholcids, including those commonly known as cellar spider, daddy long-legs spider, carpenter spider, daddy long-legger, vibrating spider, gyrating spider, long daddy, and skull spider. The family, first described by Carl Ludwig Koch in 1850, is divided into 94 genera. The common name "daddy long-legs" is used for several species, especially '' Pholcus phalangioides'', but is also the common name for several other arthropod groups, including harvestmen and crane flies. Appearance Pholcids are thin and delicate arachnids. The body, resembling the shape of a peanut, is approximately 2–10 mm (0.08–0.39 inch) in length, and the legs may be up to 50 mm (1.97 inches) long. ''Pholcus'' and ''Smeringopus'' have cylindrical abdomens and eyes arranged in two lateral groups of three and two smaller median contiguous eyes. Arrangements of eight and six ... [...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] |
Tetrophthalmi
Tetrophthalmi is an extinct suborder of Opiliones (commonly known as harvestmen or daddy longlegs) that had both median and lateral eyes. First described in 2014, it is known from two extinct species. Phylogenetic analysis suggests that this eye arrangement is the ancestral condition for harvestmen, placing Tetrophthalmi and Cyphophthalmi in a basal position within Opiliones. Classification history In the early 1980s, a tiny fossil was extracted from the Montceau-les-Mines Lagerstätte deposit in Eastern France. The fossil went unstudied for more than 30 years before paleontologist Russell Garwood used X-ray computed tomography (CT scans) to investigate the fossil. In 2014, a team led by Garwood identified the specimen as a novel species, '' Hastocularis argus'', named for the 100-eyed giant Argus Panoptes in Greek mythology. According to their analysis, the specimen died, and was rapidly buried approximately 305 million years ago. Before it decayed, its body was surrounded b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachnid
Arachnida () is a class of joint-legged invertebrate animals ( arthropods), in the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and vinegaroons. Almost all adult arachnids have eight legs, although the front pair of legs in some species has converted to a sensory function, while in other species, different appendages can grow large enough to take on the appearance of extra pairs of legs. The term is derived from the Greek word (''aráchnē'', 'spider'), from the myth of the hubristic human weaver Arachne, who was turned into a spider. Almost all extant arachnids are 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 100,000 named species, of which 47,000 are species of spiders. Morphology Almost all adult arachnids have eight legs, unli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistics (journal)
''Cladistics'' is a bimonthly peer-reviewed scientific journal which has published research in cladistics since 1985. It is published by Wiley-Blackwell on behalf of the Willi Hennig Society. ''Cladistics'' publishes papers relevant to evolution, systematics, and integrative biology. Papers of both a conceptual or philosophical nature, discussions of methodology, empirical studies on taxonomic groups from animals to bacteria, and applications of systematics in disciplines such as genomics, paleontology and biomedical epidemiology are accepted. Five types of paper appear in the journal: reviews, regular papers, forum papers, letters to the editor, and book reviews. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 5.254, ranking it 10th out of 50 journals in the category "Evolutionary Biology". Its editor-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spider
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 sep ... [...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 separat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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