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21-509: Whether spiders that weave true orb webs form a coherent group, and so should be classified together, is a question that has a long history. Two groups of spiders that spin orb webs are the Uloboridae and the Araneidae . Although their webs have a very similar overall architecture, the sticky catching threads are created in different ways. Uloborid spiders have a cribellum – a flat plate from which

42-457: A consensus over time. The naming of families is codified by various international bodies using the following suffixes: The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called the seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time

63-593: A couple of individuals to a couple hundred. These colonies may be nymph dominated or adult dominated, though a small colony dominated by adults could be a sign of the colony's slow death. These colonies show signs of being female dominated, as one would expect, with males only being found in larger colonies. This could mean males search for larger colonies, or had died out in the smaller colonies. This family has an almost worldwide distribution. Only two species are known from Northern Europe: Uloborus walckenaerius and Hyptiotes paradoxus . The oldest known fossil species

84-446: A family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to a lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching

105-542: A large group of ecribellate spiders formed the monophyletic Araneoidea . This taxon includes spiders that make orb webs, but also many that do not. At first, there was support for two hypotheses for the relationship between these two groups. Hormiga and Griswold suggested a cladogram similar to the preferred version of Blackledge et al. (2009): Non-orb-weaving spiders ( Eresoidea , RTA clade , etc.) Deinopoidea (Deinopidae + Uloboridae) Nicodamidae Araneoidea This suggests that orb-weaving evolved relatively late in

126-597: A particular kind of silk emerges – and a calamistrum – a structure formed of bristles on the metatarsus of the fourth leg, used to "comb" the cribellate silk into extremely fine strands that are adhesive without having any "glue" present. Araneid spiders have silk-producing organs that add fine droplets of a glue-like substance to silk of normal thickness to create viscid silk. (Spiders that do not spin orb webs can also be divided into those that produce cribellate silk and those that produce viscid silk.) Although cribellate and non-cribellate orb weavers had earlier been placed in

147-647: Is Talbragaraneus from the Late Jurassic ( Tithonian ) Talbragar Fossil Bed of Australia. As of May 2024 , the World Spider Catalog accepts the following genera: Family (biology) Family ( Latin : familia , pl. : familiae ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between

168-429: Is a family of non- venomous spiders , known as cribellate orb weavers or hackled orb weavers . Their lack of venom glands is a secondarily evolved trait. Instead, they wrap their prey thoroughly in silk, cover it in regurgitated digestive enzymes, and then ingest the liquified body. They are medium to large spiders, with three claws, which lack venomous glands. They build a spiral web using cribellate silk, which

189-436: Is quite fuzzy. They are usually dull in color, and are able to camouflage well into their surroundings. They typically have a humped opisthosoma , which is notoriously more humped than the carapace . Their rear eyes tend to curve, more so in some species than others. Most uloborid spiders have eight eyes, but the genus Miagrammopes has only four. The hunting method of these spiders is quite unique among all animals in

210-557: Is very rare among spiders. They first catch their prey, using their silk. They wrap their prey, and severely compress it, then they cover the prey with digestive fluid . Oddly enough, their mouthparts never touch the prey. The spider starts ingesting as soon as the prey has been covered. It is thought that robust hairs protect the spider from the digestive fluids. It is unknown how this behavior first evolved. Some species are able to form colonies like Philoponella republicana , which make large, messy, communal webs. Colonies may range from

231-414: The phylogeny of orb-weaving spiders, producing a summary based on what they considered to be the nine most comprehensive studies prior to their article. They concluded that there was limited evidence to group the cribellate Uloboridae and Deinopidae into a single taxon, Deinopoidea . (Deinopidae spin a small orb web, which they then cut loose and use as a net to catch prey.) There was strong evidence that

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252-678: The "Deinopoidea" are not monophyletic, and certainly do not form a clade with the Araneoidea. Orb webs evolved earlier, being present in the early entelegynes, and were then lost in more groups, making web evolution more convoluted, with different kinds of non-orb web having evolved separately more than once. Although some authors have said that current evidence does not allow a definitive choice between these two hypotheses, others consider that "the long-held paradigm of orbicularian monophyly" has been refuted. Further studies have supported this view, or taken it for granted. Uloboridae Uloboridae

273-506: The book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). In zoology ,

294-483: The cribellum (and hence cribellate silk), or did it evolve separately in uloborids and araneids? If it evolved only once, how early did this happen in the evolutionary history of entelegyne spiders? If late, then uloborids and araneids may form a monophyletic group, Orbiculariae. If very early, then uloborids and ananeids may not be closely related, and many more araneoids that do not spin webs would have lost this ability secondarily. In 2014, Hormiga and Griswold reviewed

315-433: The early 1970s, it had become apparent that cribellate spiders were a paraphyletic group, the cribellum being an ancient feature of araneomorph spiders that had been lost in many descendants, so that grouping spiders together based on the retention of this feature did not produce a monophyletic taxon. This still leaves open questions relating to the origin of the orb web. Did it evolve only once, with araneids later losing

336-514: The entelegynes, and that many hunting spiders never had orb-weaving ancestors. An alternative hypothesis, increasingly supported by molecular phylogenetic studies, is that the Orbiculariae are paraphyletic (i.e. do not form a good taxon). A 2016 hypothesis for the relationships of the relevant groups is shown below. Deinopidae Uloboridae Oecobiidae + Hersiliidae RTA clade (non-orb-weaving spiders) Nicodamoidea Araneoidea On this view,

357-530: The family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and

378-476: The kingdom. These spiders do not use an adhesive on their orb webs , but rather the very fine cribellate fibers on each strand of silk tend to ensnare prey. Since newly hatched uloborids lack the cribellum needed to produce cribellate sticky silk, their webs have a fundamentally different structure with a large number of fine radii, but no sticky spiral. Some spiders only build a single line web, while others make more complex webs. They lack venom glands, which

399-491: The ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family is commonly referred to as the "walnut family". The delineation of what constitutes a family— or whether a described family should be acknowledged— is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging

420-466: The same taxon (from at least 1789), the two kinds of orb weaver were placed in separate taxa after the possession of a cribellum was prioritized over the form of the web. Following John Blackwall in 1841 and Philipp Bertkau in 1878, for a long time the majority of araneologists accepted spiders with a cribellum as a coherent taxon, Cribellatae. Many also held that cribellate and ecribellate spiders had separately evolved orb webs from other kinds of web. By

441-480: Was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted the use of this term solely within

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