Crossopriza Lyoni
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''Crossopriza lyoni'' is a widespread
species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of cellar spiders that prefer to live in or around human structures. They are commonly known as tailed cellar spiders, tailed daddy longlegs spiders, and sometimes box spiders. They all possess extremely long fragile legs that can reach up to long and a body length of that ranges from . Their abdomens are distinctly squarish when viewed from the side and their
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 unde ...
is more or less circular when viewed from above. They also possess two kinds of sound-producing organs and have six eyes. The original
range Range may refer to: Geography * Range (geographic), a chain of hills or mountains; a somewhat linear, complex mountainous or hilly area (cordillera, sierra) ** Mountain range, a group of mountains bordered by lowlands * Range, a term used to i ...
of ''C. lyoni'' is unknown. They have been introduced into other parts of the world accidentally and are now
pantropical A pantropical ("all tropics") distribution is one which covers tropical regions of both the Eastern and Western hemispheres. Examples of species include caecilians, modern sirenians and the plant genera ''Acacia'' and ''Bacopa''. ''Neotropical' ...
in distribution. They are a regulated species in some countries and are often regarded as pests due to the large amounts of unsightly
web Web most often refers to: * Spider web, a silken structure created by the animal * World Wide Web or the Web, an Internet-based hypertext system Web, WEB, or the Web may also refer to: Computing * WEB, a literate programming system created by ...
s they construct inside human homes. Some people, however, regard them as beneficial, as they are efficient predators of
mosquito Mosquitoes, the Culicidae, are a Family (biology), family of small Diptera, flies consisting of 3,600 species. The word ''mosquito'' (formed by ''Musca (fly), mosca'' and diminutive ''-ito'') is Spanish and Portuguese for ''little fly''. Mos ...
es and other
arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...
s. They are harmless to humans.


Taxonomy and nomenclature

''Crossopriza lyoni'' are classified under the
genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
''
Crossopriza ''Crossopriza'' is a genus of cellar spiders that was first described by Eugène Louis Simon in 1893. Species it contains twenty-four species, found in Africa, Asia, Australia, the Americas, Germany and Micronesia: *'' Crossopriza dhofar'' Hub ...
'' and the
subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...
Holocneminae. They belong to the cellar spider family (
Pholcidae The Pholcidae are a Family (biology), family of Araneomorphae, araneomorph spiders. The family contains more than 1,800 individual species of pholcids, including those commonly known as cellar spider, daddy long-legs spider, carpenter spid ...
). They are commonly referred to as tailed daddy longlegs spiders, tailed cellar spiders, or (more rarely) box spiders. ''C. lyoni'' and other cellar spiders are also often confused with two other invertebrates - the
harvestmen The Opiliones (formerly Phalangida) are an Order (biology), order of arachnids, Common name, colloquially known as harvestmen, harvesters, harvest spiders, or daddy longlegs (see below). , over 6,650 species of harvestmen have been discovered w ...
(
order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...
Opiliones The Opiliones (formerly Phalangida) are an Order (biology), order of arachnids, Common name, colloquially known as harvestmen, harvesters, harvest spiders, or daddy longlegs (see below). , over 6,650 species of harvestmen have been discovered w ...
) and the
crane flies A crane fly is any member of the dipteran superfamily Tipuloidea, which contains the living families Cylindrotomidae, Limoniidae, Pediciidae and Tipulidae, as well as several extinct families. "Winter crane flies", members of the family T ...
(family
Tipulidae Tipulidae is a family of large Crane fly, crane flies in the order Diptera. There are more than 30 genera and 4,200 described species in Tipulidae, common and widespread throughout the world. A crane fly can be identified as a member of Tipuli ...
) - both of which are also known as 'daddy longlegs'. However, they are not closely related to cellar spiders — the latter is a
fly Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...
; and the former, while also an arachnid, is not a
spider Spiders (order (biology), order Araneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude spider silk, silk. They are the largest order of arachnids and ran ...
at all. The species was first formally described in 1867 by the
British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories and Crown Dependencies. * British national identity, the characteristics of British people and culture ...
naturalist Natural history is a domain of inquiry involving organisms, including animals, fungi, and plants, in their natural environment, leaning more towards observational than experimental methods of study. A person who studies natural history is cal ...
John Blackwall John Blackwall (20 January 1790 – 11 May 1881) was an English naturalist with a particular interest in spiders. Life Blackwall was born in Manchester on 20 January 1790. He lived at Hendre House near Llanrwst in north Wales from 1833 until ...
from a collection of spiders from
Meerut Meerut (, ISO 15919, ISO: ''Mēraṭh'') is a city in the western region of the States and union territories of India, Indian state of Uttar Pradesh. Located in the Meerut district, it is northeast of the national capital, New Delhi, and is ...
,
Agra Agra ( ) is a city on the banks of the Yamuna river in the Indian state of Uttar Pradesh, about south-east of the national capital Delhi and 330 km west of the state capital Lucknow. With a population of roughly 1.6 million, Agra is the ...
, and
Delhi Delhi, officially the National Capital Territory (NCT) of Delhi, is a city and a union territory of India containing New Delhi, the capital of India. Straddling the Yamuna river, but spread chiefly to the west, or beyond its Bank (geography ...
. They came from Francis Lyon, a captain of the
Royal Artillery The Royal Regiment of Artillery, commonly referred to as the Royal Artillery (RA) and colloquially known as "The Gunners", is one of two regiments that make up the artillery arm of the British Army. The Royal Regiment of Artillery comprises t ...
of the
British Empire The British Empire comprised the dominions, Crown colony, colonies, protectorates, League of Nations mandate, mandates, and other Dependent territory, territories ruled or administered by the United Kingdom and its predecessor states. It bega ...
stationed in
India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
. They were sent to his sister who presented them to Blackwall at the suggestion of a mutual friend. Blackwall named the spider after Captain Lyon and expressed a hope that others may follow Lyon's example in collecting specimens from foreign countries for the benefit of science. He classified the species under the genus ''
Pholcus ''Pholcus'' is a genus of spiders of long-bodied cellar spider and allies in the family Pholcidae, with 375 described species as of January 2023. It includes the cellar spider '' P. phalangioides'', often called the "daddy longlegs". This may ca ...
''. In 1892, the
French French may refer to: * Something of, from, or related to France ** French language, which originated in France ** French people, a nation and ethnic group ** French cuisine, cooking traditions and practices Arts and media * The French (band), ...
arachnologist Arachnology is the scientific study of arachnids, which comprise spiders and related invertebrates such as scorpions, pseudoscorpions, harvestmen, ticks, and mites. Those who study spiders and other arachnids are arachnologists. More narrowly ...
Eugène Simon Eugène Louis Simon (; 30 April 1848 – 17 November 1924) was a French naturalist who worked particularly on insects and spiders, but also on birds and plants. He is by far the most prolific spider Taxonomy (biology), taxonomist in history, ...
erected the genus ''
Crossopriza ''Crossopriza'' is a genus of cellar spiders that was first described by Eugène Louis Simon in 1893. Species it contains twenty-four species, found in Africa, Asia, Australia, the Americas, Germany and Micronesia: *'' Crossopriza dhofar'' Hub ...
'' and subsequently reclassified ''Pholcus lyoni'' to ''Crossopriza lyoni''. Blackwall also described a curious case of
hermaphroditism A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic. The individuals of many ...
in one adult specimen, in which the left side was male and the right side was female.


Description

''C. lyoni'' are
sexually dimorphic Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...
. Females of ''C. lyoni'' are about in length. Males are slightly smaller, at about in length, and have prominent
pedipalp Pedipalps (commonly shortened to palps or palpi) are the secondary pair of forward appendages among Chelicerata, chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to ...
s. Both sexes possess extremely long fragile legs. Males have slightly longer legs than females. The first pair of legs in larger male individuals can reach up to in length. The legs are gray to amber in color and covered with numerous small longitudinal brown spots. The 'knee joints' are brown, and the ends of the
femur The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femo ...
and
tibia The tibia (; : tibiae or tibias), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two Leg bones, bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outsi ...
e are girdled with white. Males also possess a series of 20 to 25 spines ( macrosetae) on their femur. Their leg formula is I, II, IV, III - the front pair of legs being the longest and the third pair being the shortest. The
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 ''cepha ...
is wider than it is long, greyish-white to pale amber in color. The
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 unde ...
is subcircular. In the middle of the upper surface is a deep depression (called the thoracic fovea) and a darker longitudinal band of color. ''C. lyoni'', like most other cellar spiders, has eight eyes. They are pearly-white in color and located at the tip of the cephalothorax in two lines. The abdomen (the
opisthosoma The opisthosoma is the posterior part of the body in some arthropods, behind the prosoma ( cephalothorax). It is a distinctive feature of the subphylum Chelicerata (arachnids, horseshoe crabs and others). Although it is similar in most respects ...
) is gray with white lateral stripes and various dark and light patches on the sides and the upper surface. An irregular darker stripe runs lengthwise at the bottom surface. The abdomen is angular and somewhat box-shaped, with a small conical hump on the upper back. They also possess two types of stridulatory organs. The first type is located at the posterior tips of their cephalothorax (the
prosoma 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 ''cepha ...
) in the form of two triangular protrusions. The spiders rub these structures with a matching pair of
sclerotized Sclerosis (also sclerosus in the Latin names of a few disorders) is a hardening of tissue and other anatomical features. It may refer to: * Sclerosis (medicine), a hardening of tissue * in zoology, a process which forms sclerites, a hardened exo ...
plates at the anterior portion of the abdomen, producing sound. These structures are more prominent in females. They also possess stridulatory files (in the form of a series of small ridges) on their
chelicera 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 as a type ...
e which are rubbed against the pedipalps to produce sound. The second type is more prominent in males. ''C. lyoni'' can be distinguished from other members of the genus through several ways: by the characteristic boxy shape of their abdomens ('' C. cylindrogaster'' has a cylindrical abdomen); by the presence of two apophyses (jutting structures) in the chelicerae of males ('' C. pristina'', '' C. semicaudata'', and '' C. soudanensis'' all possess only one apophysis on each chelicera); or simply by geographic distribution (''C. lyoni'' can be found globally and is the only species of ''Crossopriza'' in the
New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...
, while the other species like '' C. johncloudsleyi'' and '' C. nigrescens'' are restricted to
Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...
or the
Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...
).


Ecology and life cycle

A single male ''C. lyoni'' is able to copulate with several females. Mating is accomplished with the male inserting both his pedipalps into the genital orifice of the female and transferring a previously prepared packet of sperm into her
spermatheca The spermatheca (pronounced : spermathecae ), also called ''receptaculum seminis'' (: ''receptacula seminis''), is an organ of the female reproductive tract in insects, e.g. ants, bees, some molluscs, Oligochaeta worms and certain other in ...
e. Because of the relative shortness of the male pedipalps in comparison to the sheer length of the legs of both males and females of the species, the spiders have to bring their bodies close together, giving the impression of 'snuggling'. This lasts for about 40 minutes. In rare instances, females may eat the males after copulation. The eggs are deposited by the females 5–6 days after copulation. After laying the eggs, females will bind them into a ball with tiny amounts of silk. They then clutch the resulting egg sacs with their mouthparts and carry them around (a behavior common among all cellar spiders). Eggs that somehow fall from the loose bundles do not hatch. The females still feed during this period, setting their burdens aside temporarily while they eat, then picking them up again. They also frequently adjust their grip. Instances of females eating some of their own eggs have been recorded. It is assumed that they only consume the infertile ones, as unfertilized eggs occur at high enough rates among ''C. lyoni''. 5 to 54 spiderlings will eventually hatch from the eggs, 11 to 13 days after egg-laying. Spiderlings do not leave the eggs immediately. They hatch partially, but otherwise remain in the bundle their mothers carry for at least a day. They eventually leave it completely. They remain mostly inactive for 2 to 3 days after hatching until their first
molt In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at ...
. Spiderlings which are separated from their mothers mature more rapidly than those which remained nearby. They become adults approximately 80 days after hatching. ''C. lyoni'' has a lifespan of at least 194 days (around 6 and a half months). ''C. lyoni'' are active hunters. Hanging upside down, they will quickly capture prey caught in their irregular
cobweb A spider web, spiderweb, spider's web, or cobweb (from the archaic word '' coppe'', meaning 'spider') is a structure created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey. Spider w ...
-like webs. If hungry enough, they also actively pursue prey that fly close to their webs. They do not use their fangs when hunting, throwing silk over prey instead and then wrapping them loosely using their hind legs. They will only bite them when they start to feed, which can sometimes be as long as six days after capture. They also actively clean their webs by removing carcasses regularly. When webs become too dirty, they build new ones. Newly hatched spiderlings are just as active as adults. 2 to 4 days after their first molt, spiderlings can already overpower mosquitoes four times their own size. Spiderlings may share prey they caught themselves or prey caught by their mother. They may also engage in
cannibalism Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is also well document ...
by preying on their own siblings. ''C. lyoni'', like other cellar spiders, will violently gyrate their bodies in small circles when threatened. They can do this very rapidly, blurring their outline and making them very difficult to see. This behavior earned cellar spiders one of their common names - 'vibrating spiders' - and is presumed to be an
antipredator adaptation Anti-predator adaptations are mechanisms developed through evolution that assist Predation, prey organisms in their constant struggle against predators. Throughout the animal kingdom, adaptations have evolved for every stage of this struggle, na ...
. If this does not work, they will drop from their webs to the ground, or flee awkwardly with their characteristic long-legged gait.


Distribution and habitat

''C. lyoni'' are
synanthropic A synanthrope (from ancient Greek σύν ''sýn'' "together, with" and ἄνθρωπος ''ánthrōpos'' "man") is an organism that evolved to live near humans and benefit from human settlements and their environmental modifications (see also ...
, preferring to live inside or near human-made structures. They usually build large irregular webs in corners of rooms, basements, cellars, and beneath ceilings. They are readily transported by human activity, especially as hitchikers in ships. As a result, ''C.lyoni'' has been introduced to most of the world, including
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
,
Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...
,
Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...
,
Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...
,
North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating Direction (geometry), direction or geography. Etymology T ...
and
South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...
, and some
Pacific islands The Pacific islands are a group of islands in the Pacific Ocean. They are further categorized into three major island groups: Melanesia, Micronesia, and Polynesia. Depending on the context, the term ''Pacific Islands'' may refer to one of several ...
. Their place of origin is unknown but have been variously posited to be Africa (where their genus has the highest diversity) or somewhere in Asia.


Relations with humans

''C. lyoni'' are a regulated
invasive species An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...
in several countries. While doing no appreciable damage to humans, they are sometimes regarded as pests due to the large amounts of unattractive webs they construct inside houses. Unlike most spiders which consume their old webs before building new ones, cellar spiders simply abandon their old webs. There are often hundreds of individuals representing different generations living in close proximity to each other in a given area. Methods of controlling them can be as direct as simply using a
broom A broom (also known as a broomstick) is a cleaning tool, consisting of usually stiff fibers (often made of materials such as plastic, hair, or corn husks) attached to, and roughly parallel to, a cylindrical handle, the broomstick. It is thus a ...
or a
vacuum cleaner A vacuum cleaner, also known simply as a vacuum, is a device that uses suction, and often agitation, in order to remove dirt and other debris from carpets, hard floors, and other surfaces. The dirt is collected into a dust bag or a plastic bin. ...
to remove the webs. Preventive measures mostly focus on reducing the amounts of insect prey around the house. This includes changing exterior white lights to yellow or sodium vapor lights, colors which are less attractive to insects. Sealing small entry points can also prevent both insect and spider access into the house.
Insecticide Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...
s can also be used, but is usually only effective for a relatively short amount of time. Some people regard ''C. lyoni'' spiders as beneficial. Adult ''C. lyoni'' can consume 12 to 20
mosquito Mosquitoes, the Culicidae, are a Family (biology), family of small Diptera, flies consisting of 3,600 species. The word ''mosquito'' (formed by ''Musca (fly), mosca'' and diminutive ''-ito'') is Spanish and Portuguese for ''little fly''. Mos ...
es (''
Aedes ''Aedes'' (also known as the tiger mosquito) is a genus of mosquitoes originally found in tropical and subtropical zones, but now found on all continents except Antarctica. Some species have been spread by human activity: ''Aedes albopictus'', ...
'' sp.) a day, in addition to other insect pests. Their effects on containing the populations of mosquitoes (''Aedes'', ''
Anopheles ''Anopheles'' () is a genus of mosquito first described by the German entomologist Johann Wilhelm Meigen, J. W. Meigen in 1818, and are known as nail mosquitoes and marsh mosquitoes. Many such mosquitoes are Disease vector, vectors of the paras ...
'', ''
Culex ''Culex'' or typical mosquitoes are a genus of mosquitoes, several species of which serve as vectors of one or more important diseases of birds, humans, and other animals. The diseases they vector include arbovirus infections such as West Nil ...
'', etc.) and other disease-transmitting
arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...
s harmful to humans seems to be significant. In areas where mosquito-borne diseases (like
dengue fever Dengue fever is a mosquito-borne disease caused by dengue virus, prevalent in tropical and subtropical areas. Asymptomatic infections are uncommon, mild cases happen frequently; if symptoms appear, they typically begin 3 to 14 days after i ...
) are present, it is recommended to avoid removing natural populations of ''C. lyoni''. Studies have also shown that ''C. lyoni'' spiders that eat
dengue virus Dengue virus (DENV) is the cause of dengue fever. It is a mosquito-borne, single positive-stranded RNA virus of the family ''Flaviviridae''; genus '' Flavivirus''. Four serotypes of the virus have been found, and a reported fifth has yet to be ...
-infected mosquitoes do not seem to acquire the virus themselves. A study in 2009 showed that the
web Web most often refers to: * Spider web, a silken structure created by the animal * World Wide Web or the Web, an Internet-based hypertext system Web, WEB, or the Web may also refer to: Computing * WEB, a literate programming system created by ...
s of ''C. lyoni'' exhibit antibacterial properties against ''
Escherichia coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly fo ...
'', ''
Pseudomonas aeruginosa ''Pseudomonas aeruginosa'' is a common Bacterial capsule, encapsulated, Gram-negative bacteria, Gram-negative, Aerobic organism, aerobic–facultative anaerobe, facultatively anaerobic, Bacillus (shape), rod-shaped bacteria, bacterium that can c ...
'', ''
Staphylococcus aureus ''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often posi ...
'' and others.
Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain ...
were more vulnerable to the proteins from ''C. lyoni'' webs than
Gram-negative bacteria Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the Crystal violet, crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelo ...
. ''C. lyoni'' and other pholcids are often the subject of a popular
urban legend Urban legend (sometimes modern legend, urban myth, or simply legend) is a genre of folklore concerning stories about an unusual (usually scary) or humorous event that many people believe to be true but largely are not. These legends can be e ...
about how they are the most venomous known animals except that 'their fangs are too small to penetrate human skin'. While they do possess potent
venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...
against insects and other spiders (some cellar spiders, for example, prey on deadly
redback spider The redback spider (''Latrodectus hasselti''), also known as the Australian black widow, is a species of highly venomous spider believed to originate in Australia, but which is now found in Southeast Asia and New Zealand. It has also been fo ...
s in
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
), their venom is not harmful to humans.


See also

*
List of Pholcidae species This page lists all described genera and species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reprod ...
*''
Pholcus phalangioides ''Pholcus phalangioides'', commonly known as the cosmopolitan cellar spider, long-bodied cellar spider, or one of various types called a daddy long-legs spider, is a spider of the family Pholcidae. It was first described in 1775 by the Swiss En ...
'', another widespread synanthropic cellar spider *
Spider cannibalism Spider cannibalism is the act of a spider consuming all or part of another individual of the same species as food. It is most commonly seen as an example of female sexual cannibalism where a female spider kills and eats a male before, during, or ...


References


External links


Pholcidae - the longest legs in the web
maintained by Bernard A. Huber and the
University of Bonn The University of Bonn, officially the Rhenish Friedrich Wilhelm University of Bonn (), is a public research university in Bonn, North Rhine-Westphalia, Germany. It was founded in its present form as the () on 18 October 1818 by Frederick Willi ...

Pholcidae ~ Cellar Spiders
fro

{{Taxonbar, from=Q1318127 Pholcidae Spiders of Europe Articles containing video clips Pantropical spiders Spiders described in 1867