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Die Opuntienspinne (Cyrtophora citricola) ist eine im Mittelmeerraum häufig anzutreffende Spinnenart aus der Familie der Echten Radnetzspinnen.
Die Opuntienspinne ist etwas kleiner als die bekannte Gartenkreuzspinne, wobei der Größenunterschied zwischen den Geschlechtern bei Cyrtophora citricola aber viel größer ist: Männchen haben eine Körperlänge von 2 bis 4 mm, Weibchen werden 10 bis 15 mm lang.
Der Vorderkörper (Prosoma) ist einfarbig hell beigebraun oder schwarz und stark weiß behaart. Der weniger dicht behaarte Hinterkörper (Opisthosoma) ist länglich-oval und trägt drei Paare sehr auffälliger Höcker. Die Höcker befinden sich an der Vorderkante, etwa auf Höhe des ersten Drittels sowie am Ende des Opisthosomas und weisen jeweils leicht nach außen. Die Grundfärbung des Opisthosomas ist entsprechend dem Prosoma entweder recht einheitlich gelblich braun oder schwarz. Es zeigt in der Mitte ein Band unregelmäßiger, dunkler und hell gerandeter, schmal-lanzettlicher oder ovaler Flecken und außerdem drei seitlich angeordnete paarige Flecken. Diese sind bei bräunlichen Tieren schwärzlich, bei schwarzen Tieren jedoch sehr auffallend leuchtend weiß.
Die Beine sind bei bräunlichen Tieren nicht sehr kontrastreich hell/dunkel geringelt, bei schwarzen Tieren hingegen ebenfalls einfarbig schwarz.
Die Opuntienspinne besiedelt große Teile der Tropen und Subtropen der Alten Welt.[1] Auf dem amerikanischen Kontinent wurde die Art erstmals 1996 in Kolumbien nachgewiesen, und sie breitet sich seitdem offenbar in der Neuen Welt schnell aus.[2][3] In der Dominikanischen Republik wurde sie 1999 nachgewiesen, in Florida im Jahr 2000, in Kuba und Brasilien 2003.
In Europa kommt die Art in Portugal, Spanien, Frankreich, Italien einschließlich Sizilien und Sardinien, in Griechenland sowie auf Malta vor. Ferner sind Madeira und die Kanarischen Inseln besiedelt.[4]
Neben der Nominatform werden drei Unterarten unterschieden[1]:
Die Art bewohnt sonnenexponierte Bereiche mit niedriger, sehr stabiler Vegetation, im Mittelmeerraum befinden sich die Netze meist in dort eingebürgerten Opuntien. Geschlechtsreife Individuen treten im Mittelmeerraum von Juni bis September auf.
Die Netze der Opuntienspinne zählen zu den komplexesten Spinnennetzen – für den Bau benötigen die Weibchen mehrere Nächte. Die Spinne baut ein horizontales Radnetz, das einen Durchmesser von 50 bis 60 Zentimetern erreicht. Die Netzmitte ist trichterförmig nach oben erweitert; dort befindet sich das Versteck der Spinne. Von diesem zentralen Trichter aus werden Radien nach außen gezogen. Überschreitet der Abstand zwischen den Radien etwa einen Millimeter, zieht die Spinne dazwischen einen weiteren Radius ein, so dass die Anzahl der Radien von innen nach außen immer mehr zunimmt. An diesen Radien wird dann eine sehr enge Fangspirale befestigt, die im Gegensatz zu allen übrigen Radnetzspinnen nur aus einem glatten Faden besteht und keine Klebetropfen aufweist. Dieses Radnetz wird nach unten mit Spannfäden stabil verankert. Über dem Radnetz werden überall zahlreiche „Stolperfäden“ eingezogen, so dass fliegende Beute, die gegen diese stößt, auf das Radnetz fällt. Die Spinne eilt dann von unten heran, greift die Beute von unten durch das Netz, wickelt sie ein und trägt sie ins Versteck im Trichter.
Die Weibchen legen im Sommer mehrere Kokons an, diese werden untereinander über dem zentralen Trichter befestigt, so dass ein wurstförmiges Gebilde entsteht.
Die Art ist in geeigneten Lebensräumen häufig und ungefährdet.
Die Opuntienspinne (Cyrtophora citricola) ist eine im Mittelmeerraum häufig anzutreffende Spinnenart aus der Familie der Echten Radnetzspinnen.
Cyrtophora citricola, also known as the tropical tent-web spider, is an orb-weaver spider in the family Araneidae. It is found in Asia, Africa, Australia, Costa Rica, Hispaniola, Colombia, and Southern Europe and in 2000, it was discovered in Florida. C. citricola differs from many of its close relatives due its ability to live in a wide variety of environments. In North America and South America, the spider has caused extensive damage to agricultural operations.
C. citricola is in the orb web spider family, but its orb webs are considered atypical. They have a thick silk strand barrier above the orb and a thinner barrier below the orb. This gives the webs a horizontal mesh-like appearance. The spider has developed distinct and specific prey-capturing techniques using its unconventional webs. The prey flies into the upper mesh layer of the web and is deflected into the orb web. The spider then collects and stores the prey in its web. The difference in C. citricola's web silk stems from physiological variations in its spinning apparatuses, as compared to other closely related species. Its webs are non-adhesive and do not require daily respinning.
This spider is one of the few species to exhibit a variable level of sociality. C. citricola can be seen in colonies, which may have arisen due to reduced predation. Within these colonies, each spider has its own web that is linked to other spiders through communal webbing. The spider webs are often built in large matrices next to one another and can span entire trees. The spider usually peacefully coexists with other spiders in the colony. However, at times the spider may have to ward off other spiders in the colony that may try and claim its web.[1]
C. citricola is nocturnal, only performing necessary tasks during the day. During the day, it remains idle and tries to stay out of sight from predators. Most of its foraging and prey capture happen at night.[2]
C. citricola's color and size can vary greatly. Many spiders sport a black and white pattern while others are brown. Males often appear black. Male and female spiders have a sexual dimorphism. The body length in females normally reaches 10 millimetres (0.39 in), while males are only 3 millimetres (0.12 in) long.
Peter Forsskal discovered Cyrtophora citricola in the Arabian Peninsula during his Yemen expedition, sometime between 1761 and 1763.[3] He first saw the spiders in citrus trees and described their horizontal webs as nets. The spider's common name, “tropical tent-web,” derives from these observations.[4] Unfortunately, Forsskal died in Yemen in 1763. His manuscripts, which included details of the spider, were collected and sent back to Denmark by his friend Carsten Niebuhr.[3] These records were published in 1775 as Descriptiones animalium, avium, amphibiorum, piscium, insectorum, vermium; the spider appeared under the name Aranea citricola.[4] C. citricola was classified in the Araneidae family because it creates orb-webs.[1] Between 1776 and 1864, the spider was classified under the genus Epeira, a synonym for Aranea, more commonly known as Araneus. The spider was moved from the genus Aranea to the genus Cyrtophora by Eugene Simon in 1864 – a decision made because its webs were so different from those constructed by other spiders in the genus Aranea.[5] C. citricola webs are horizontal and tent-shaped, similar to those of other spiders in the genus Cyrtophora. Like other members of Cyrtophora, C. citricola's 2nd, 3rd, and 4th pairs of legs have a shorter combined patella and tibia length than the femurs on the same legs. Additionally, it shares the same eye pattern where the posterior eye row is recurved: a typical genus-defining trait. C. citricola has broader cephalic structures than other orb-web spiders in the genus Manogea.[6]
Cyrtophora citricola falls into the family Araneidae because of three characteristics. The male's palpal faces the mesial, or midline of the body. The male spider's palpal has an exoskeleton on their bulbous known as a radix, and the spider has a thin reflective layer of tissue in the posterior set of its eyes called the tapetum.[7] C. citricola differs from “derived araneoids”, which are a part of the superfamily Araneoidea, such as Theridion and Linyphiidae, because it lacks smaller aciniform spigots in their median spinnerets. These spigots each individually produce a strand of aciniform silk, the strongest type of spider silk.[8] C. citricola is a part of the argiopoid clade because there is a sexual dimorphism between males and females. Female are larger than males. The sexual dimorphism present in C. citricola separates them from members of the Araneinae subfamily including Nuctenea, Cyclosa, and Mangora.[7] C. citricola is a part of the Cyrtophorinae subfamily and shares the sexual dimorphism trait with the Argiopinae, Gasteracanthinae, and Micratheninae subfamilies. Within the argiopoid clade, C. citricola is a member of the argiopine clade because the upper section of its exoskeleton is hairy.[7] This trait distinguishes C. citricola from the Gasteracanthinae and Micratheninae subfamilies. Within the argiopine clade, C. citricola is a member of the Cyrtophorinae family, which includes the genera Cyrtophora and Manogea. Cyrtophorinae's subfamily defining features are its embolus, the palpal bulb's open duct, running in a counterclockwise direction, and its non-adhesive orb-webs.[7]
Cyrtophora citricola occurs in various colors and may have different colored spots on the abdomen. The spider is sexually dimorphic. Females may reach 10 millimetres (0.39 in) long and are larger than their male counterparts who are usually 3 millimetres (0.12 in) long. C. citricola's legs are different lengths with legs I and II being the longest.[6] In Florida, male spiders are black, while females can change the color of their abdomens to match their surroundings and can camouflage in their webs. The females have white trichobothria. In Turkey, they usually appear brown with grey hair. C. citricola has a distinctive horizontal bifurcation at the posterior abdomen.[9][10] C. citricola is different from its other relatives because it has two pairs of dorsal tubercles and a pair of posterior tubercles.[6] C. citricola typically has seven denticles. The opisthosoma has two dorsal pairs of protuberances and two posterior lobes.[11] C. citricola has two rows of eyes. The largest eyes are the two median eyes in the anterior row.[12] In some places, C. citricola may be confused with Mecynogea lemniscata.[13]
Cyrtophora citricola is found in Asia, Africa, Australia, Costa Rica, Hispaniola, Colombia, and Southern Europe.[2] The species is unable to survive in temperatures below -1°C (30.2°F).[10] C. citricola was also discovered in Florida in 2000 and it makes its webs on canal bridges from the east end of Everglades National Park to the east coast. The spider lives in a wide range of environments, but it is most prevalent in olive orchards and undergrowth.[6] C. citricola is also found in tropical agricultural operations.[2]
C. citricola can be found globally, unlike its close relatives that are concentrated in specific parts of the world. C. citricola's global presence may be a problem as seen in the Americas.[14] The spider is becoming common in agricultural and urban spaces. It is damaging farm operations. Currently, there are active efforts to remove the spider as its web is known to damage flora.[9]
C. citricola exhibits thermoregulative behaviors. This trait is common in web-building spiders, including Nephila clavipes, N. maculata, and Frontinella communis. During the hottest portions of the day, the spider will position themselves so that as little surface area of their body is shown to the sun as possible.
Cyrtophora citricola builds tent-webs that have a horizontal orb web and a network of webs above it resembling a tent.[1] These webs can be built alone or as part of a colony. The spiders exhibit advantages living in colonies, but there is no selection towards either solitary or colonial living.[15] Within colonies, the horizontal orb webs are solitary and maintained by individuals.[2] Other Araneidae species have a triad complex on their posterior spinnerets which produce a gluey thread material for the webs from the piriform glands. C. citricola lacks a triad complex and is unable to make gluey thread web material so it creates a distinct non-sticky, mesh-like web.[16]
C. citricola creates a thick silk strand barrier above the orb and a thinner barrier below the orb. The silk above the web is used to deflect insects onto the orb web below.[1] The webs above and below the horizontal orb webs are communal and maintained by the colony.[2] The horizontal orb web and silk are not sticky.[1][10] The orb webs appear as a fine mesh curtaining, made of radii and a non-adhesive structural spiral. This structure is different than the typical Araneidae family webs, as they lack a viscid spiral. These webs are durable, and may have evolved to be created outside of citrus trees. The webs may be large enough to span entire trees and are found on a variety of tree species.[9][10] C. citricola prefers to build its webs on firm substrates rather than non-firm substrates. Webs built on firmer substrates tend to last for longer periods of time.[17] The webs are strong enough to withstand environmental pressures, such as rain and wind.[18] Unlike adhesive webs, which must be respun daily, non-adhesive webs are only repaired when damaged. Most of this damage occurs at the peripheries of colony webs where the costs to create orb-webs is high. The center of these colonies infrequently require repairs, saving the spider the constant investment of respinning the web.[1]
C. citricola typically rests with all of its legs underneath its body when it is not watching over its egg sacs and uses various motions to detect prey and intrusions. The spider sits on the hub of the web. This positioning occurs during the night and day.[18] C. citricola also participates in web jerking, an act of quickly pulling the radii with a front leg. Web jerking may occur in response to movement in the web and prey capturing. The behavior may allow the spider to accurately find objects in its web, assist in prey location, and transmit signals.[18] In addition, the spider engages in web shaking, motions that cause sudden and rapid shaking of its webs. This shaking is created by a downward motion from the spiders' legs. C. citricola engages in web shaking to dislodge prey stuck in the upper barrier of the web. It may also shake off approaching kleptoparasites.[18]
C. citricola captures its prey in the upper section of the web. The rate of prey per capita due to web deflection is relatively low and may cause spiders to aggregate together.[1] Spiders who live in social aggregates are more efficient at capturing prey than solitary spiders.[1][10]
The process of capturing prey includes multiple steps. The first step is either biting the prey or wrapping it in silk. The second step is pulling and cutting the prey out of the web. The third step involves transporting the prey to the hub of the web by either carrying it in its jaws or rewrapping it and carrying it in silk. In the fourth step, the spider feeds on the prey in the hub of the web.[18]
C. citricola has four attack sequences. In the first variation, the spider wraps its prey and bites it. After biting the prey, the spider removes the prey from the web, rewraps it, and transports it to the hub. The second sequence follows the steps of the first variation but skips the biting stage. The third variation starts with the spider biting its prey and wrapping its prey. Later, the prey is removed and rewrapped before being transported to the web hub. The fourth sequence involves spiders biting and pulling or cutting the prey. The prey is transported to the hub in the spider's jaws. Whether the prey is bitten, wrapped, or both is determined by the type of prey that is captured.[18]
C. citricola preys on moths and flies. These insects are bitten and carried to the hub on silk. Orthopteras are also captured and eaten by C. citricola using a variety of the above sequences. Other common prey include dragonflies, beetles, and pentatomids.[18]
C. citricola is active from the middle of summer to the beginning of fall and adults mate between June and September.[6] Adult male spiders look for females.[19] These spiders exhibit sexual cannibalism at high rates. Female spiders will often eat males after mating.[20] Females cannibalize males after most successful copulations, up to 100% of the time. Spider age and feeding state have no effect on whether the male will be cannibalized. This sexual cannibalism encourages males to be choosy when picking a female mate. Males prefer to mate younger, well-fed, and virgin females. Females are not as choosy in their male mates, but may prefer well-fed and older males. About 50% of females re-mate within ten days after their first copulation. Sexual cannibalism forces monogamy on the male spiders.[20]
The female begins the mating process. Females traditionally approach the male until they are 1cm from the male. At this point, the male advances quickly towards the female and tries to insert his pedipalp. If successful, copulation begins and lasts for a few seconds. This is the stage at which copulation most often fails.[20]
Unlike other cannibalizing spiders, the male C. citricola does not somersault into the female's chelicerae. The female bends her cephalothorax and orients herself to attack the male's abdomen while the pedipalp is in the female. The male is eaten and the pedipalp is detached from the female.[20]
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C. citricola may exhibit aggregate social interactions with one another and live cooperatively in groups.[2] This behavior is distinct amongst spiders, as most spiders are solitary.[1] C. citricola make their own individual webs, but these webs are interconnected. This large network of webs with neighboring spiders creates a massive web matrix. Given the large size and visibility of the colonial web, prey who are visually acute may avoid approaching the colony.[1] If one member of a colonial group senses a nearby predator or prey, they perform a knee jerk on the web. This jerk often begins a chain reaction; up to 75% of nearby spiders may follow suit and jerk their webs as well.[1] Within colonies, there are three zones where spiders may live: the outside, the intermediate, and the inside zones. Spiders living in the intermediate zone have the best rates of prey capture.[2] Larger colonies have higher prey capture rates compared to smaller colonies and capture rates are higher for spiders at night compared to day.[1]
C. citricola generally coexist peacefully. They may exhibit aggressive behaviors if another spider tries to take their prey.[10][20][22] Colony living may have evolved because of the foraging benefits of group living for the spiders, although solitary living may be favored when prey is scarce. Conditional sociality is another evolutionary explanation for why group living evolved in this species.[15] Possibilities for this development may be protection against parasites or predators and how colonial webs allow juveniles to easily create their first webs.[2]
Some C. citricola live individually with no colony, alone without other organisms. Solitary spiders have larger webs, produce more eggs, and have more kleptoparasites than colonies. There is no difference in female size and prey capture rates when comparing colonial and solitary spiders. There are two hypotheses for the limited physical differences between solitary and colonial spiders. The first hypothesis is that spiders can move back and forth between colonial and solitary living throughout their lives. The second hypothesis is that prey capture is similar in both colonial and solitary spiders, allowing for similar physical development. Both hypotheses may explain the many similarities between solitary and colonial spiders.[2]
C. citricola exhibits territorial behavior over its orb-webs, but tent webs are communal and no aggressive behavior was documented between spiders that travel across these webs. At night there are conflicts between orb-less spiders and orb-possessing spiders. These fights occur due to competition for better feeding locations. Larger spiders typically win in fights over smaller spiders.[15] Invading spiders may come from the colony's periphery, where costs to build webs are often high due to continuous repair and diminished prey capture. Peripheral webs often experience damage from weather and predators whereas central webs remain undisturbed.[1] Conflict arises when an orb-less intruder approaches and vibrates the web. This action is a sign of attack and solicits the same response from the defending spider. The vibrations between the attacker and the defender continue for a few minutes; however, the invader rarely captures the web and instead it retreats.[1]
The egg sacs of C. citricola have a diameter ranging from 12–20 millimetres (0.47–0.79 in). These egg sacs are laid in chains of up to 10 sacs in a row on the webs. The eggs are colored bluish-green. Each egg sac contains between 100 and 200 eggs and the eggs are shaped as flat ellipticals.[10][20] The number of eggs produced depends on various environmental factors, including food availability. Solitary females can produce up to 20% more eggs than females living in colonies.[2] The reduction of eggs in colonies may be due to better parasite protection and reduced predation.[20] Females with egg sacs will typically rest directly underneath the egg sac in order to guard them.[18]
Juveniles usually disperse or build their own webs off the maternal webs after four days.[23] Juveniles in larger webs are less likely to leave their mother's web. Mothers feed offspring, but when prey is scarce there is increased sibling aggression. These resource-poor conditions increase the likelihood of early dispersal from the maternal web.[23]
C. citricola prefers to select nest sites and create webs in the forks between branches and leaves.[24]
Argyrodes argyrodes, another species of spider, may steal Cyrtophora citricola's prey and eggs.[2][10] In addition, Holocnemus pluchei, also known as daddy long-legs, has been found to build their webs off of C. citricola's webs. H. pluchei exhibit aggressive behavior towards C. citricola and are observed eating C. citricola juveniles.[2] C. citricola will drop to the ground if attacked, in an attempt to camouflage.[19] C. citricola may also pull all of its legs inwards towards its abdomen.[18]
A. gibbosus often acts as a kleptoparasite to C. citricola, stealing prey that the C. citricola caught.[2] A. gibbosus is known to switch strategies depending on where the host is located. Prey is stolen when the host is in the hub of the web. A. gibbosus has been observed waiting for C. citricola to go foraging before consuming their eggs.[25]
Pediobius pyrgo is a type of wasp that lays its eggs in C. citricola egg sacs. The wasp is present in the Iberian Peninsula and in the Canary Islands.[26] Philolema palanichamyi is another type of wasp that lays its eggs in C. citricola egg sacs. The wasp affects these spiders primarily in the Canary Islands and can parasitize around 40% of egg sacs. Wasp larvae feed on the spider's eggs and each larva will devour significant portions of the egg sacs; incubation lasts approximately seven weeks. Wasp larvae often cause a large portion of parasitized spider egg-sacs to die. Parasitization decreases emerging spiderling populations by approximately 60%.[26]
Cyrtophora citricola can change its abdomen's color to blend in with the environment.[1] The coloring of the female Floridian spiders allows them to appear as brown, dead leaves when sitting in their webs, preventing potential predators from spotting them.[9][10]
Ornamental trees, fruit trees, and various flowering plants in the genus Eugenia including E. coronata, have high concentrations of Cyrtophora citricola. These plants and trees may experience incomplete death when C. citricola's webs span over their leaves.[9][10] This may be due to the thickness of the webs that can restrict airflow to the leaves. As a result, some authorities have opted to use high-pressure water sprayers and chemical controls to exterminate colonies.[10]
C. citricola is problematic for many agricultural operations in South America, including coffee and citrus plantations. It is listed as an important agricultural pest in the Dominican Republic due to its devastating impact on citrus trees.[27] Additionally, it is increasingly common in the Southern states of North America. In Florida, the spider has become a common backyard nuisance.[26]
{{cite journal}}: CS1 maint: DOI inactive as of December 2022 (link) Cyrtophora citricola, also known as the tropical tent-web spider, is an orb-weaver spider in the family Araneidae. It is found in Asia, Africa, Australia, Costa Rica, Hispaniola, Colombia, and Southern Europe and in 2000, it was discovered in Florida. C. citricola differs from many of its close relatives due its ability to live in a wide variety of environments. In North America and South America, the spider has caused extensive damage to agricultural operations.
C. citricola is in the orb web spider family, but its orb webs are considered atypical. They have a thick silk strand barrier above the orb and a thinner barrier below the orb. This gives the webs a horizontal mesh-like appearance. The spider has developed distinct and specific prey-capturing techniques using its unconventional webs. The prey flies into the upper mesh layer of the web and is deflected into the orb web. The spider then collects and stores the prey in its web. The difference in C. citricola's web silk stems from physiological variations in its spinning apparatuses, as compared to other closely related species. Its webs are non-adhesive and do not require daily respinning.
This spider is one of the few species to exhibit a variable level of sociality. C. citricola can be seen in colonies, which may have arisen due to reduced predation. Within these colonies, each spider has its own web that is linked to other spiders through communal webbing. The spider webs are often built in large matrices next to one another and can span entire trees. The spider usually peacefully coexists with other spiders in the colony. However, at times the spider may have to ward off other spiders in the colony that may try and claim its web.
C. citricola is nocturnal, only performing necessary tasks during the day. During the day, it remains idle and tries to stay out of sight from predators. Most of its foraging and prey capture happen at night.
C. citricola's color and size can vary greatly. Many spiders sport a black and white pattern while others are brown. Males often appear black. Male and female spiders have a sexual dimorphism. The body length in females normally reaches 10 millimetres (0.39 in), while males are only 3 millimetres (0.12 in) long.
Cyrtophora citricola, l'Épeire de l'Opuntia, est une espèce d'araignées aranéomorphes de la famille des Araneidae[1].
Cette espèce se rencontre en Afrique, en Europe du Sud, en Asie et en Australie. Elle a également été observée dans les Caraïbes et au Brésil dans les zones urbanisées à la suite d'introductions[1],[2].
Sur le territoire français, elle est présente à La Réunion[3] et en Corse[4] ; elle est attestée dans le Var et signalée à Marseille et sur la Côte d'Azur[5],[6].
Il s'agit de la seule espèce du genre Cyrtophora présente en Europe[4].
La femelle mesure de 7,5 à 13,3 mm et le mâle 2,7 mm[7].
La forme de l'abdomen est caractéristique et présente six tubercules nets, soulignés par des taches blanches. La couleur abdominale est variable. Le céphalothorax est brun sombre, couvert de longs poils blancs. Il existe une forme claire (beige) et une sombre (anthracite à noir). Le mâle, assez sombre est particulièrement petit par rapport à la femelle (dimorphisme sexuel ). Il ne tisse pas de toile et vit dans celles des femelles.
Les toiles sont construites dans la végétation, notamment les Opuntias, les Agaves et les Euphorbes cactiformes comme aux Canaries[8], parfois aussi dans l'habitat humain. Des agrégations de toiles sont possibles et fréquentes, les araignées ayant alors une vie sub-coloniale.
Du point de vue structural, chacune d'elles est un édifice soyeux tridimensionnel complexe, évoquant à première vue la construction habituelle des Linyphiidae, fort dissemblable de l'orbe classique tissée par les "Epeires" et les "Argiopes", de ce fait "aberrant" dans la famille des Araneidae surtout composée d'orbitèles typiques[9].
Il est totalement dépourvu de fils gluants et comporte une nappe horizontale de pourtour arrondi que soutiennent deux réseaux irréguliers, sus et sous-jacents. La nappe est formée d'innombrables radii et d'un fil spiral sans gouttelettes visqueuses, donc non adhésif. En se croisant, ces fils constituent un tissu robuste, avec des jonctions en nombre extraordinairement élevé et dont les petites mailles carrées sont si fines et si régulières qu'elles évoquent la structure d'un filet à plancton (Fig. 2). Le tissu s'incurve en dôme ou en entonnoir surbaissé, unique, mais pouvant être aussi multiple.
Le mâle pygmée n'a en revanche qu'une activité séricigène réduite se limitant au tissage d'un petit réseau irrégulier pour son repos, de la toile spermatique et du « fil de cour ». Toutes ces structures sont fixées sur la propre toile de la femelle, comme d’ailleurs les petits édifices par des jeunes sorties de leur cocon[9].
La toile remplit plusieurs fonctions : abri pour la femelle qui s’y tient généralement ventre en l’air sur la face inférieure du dôme maillé, capture des proies en jouant le rôle d’une « nasse » pour les Insectes volants que les fils barrière du réseau supérieur projettent sur la nappe où l’araignée les saisit à travers son tissu avant de les mordre avec ses chélicères et de les emmailloter, réserve hydrique, stockage des restes de proies et de débris végétaux assurant son camouflage et lieu unique pour la mise en place des cocons tissés par Cyrtophora citricola autour de ses œufs. En nombre variable (Fig. ), ces cocons sont orbiculaires, plus ou moins plan-convexes, blancs à verdâtres et disposés au-dessus du moyeu en une file verticale éminemment caractéristique[9].
Il est à noter que de petites Araignées Theridiidae du genre Argyrodes fréquentent assiduement les toiles de Cyrtophora citricola dans les régions tropicales et subtropicales[3]. Remarquables par leur dimorphisme sexuel lié à la présence d'une glande clypéale ou acronale, ces commensaux kleptoparasites dérobent de la nourriture à la Cyrtophora qui les héberge ou en dévorent même les jeunes.
Très grande et d'architecture complexe, la toile de Cyrtophora citricola est complètement dépourvue de spirale adhésive comme chez les autres Araignées du même genre[9]. Les corollaires de cette particularité sont évidents dans les coupes histologiques de l'appareil séricigène : le grand développement des glandes ampullacées, susceptibles d'élaborer une quantité de soie considérable ; l'absence totale de l'unité fonctionnelle à l'origine de la spirale captrice des toiles, cette triade étant normalement formée par des glandes agrégées, productrices de la glu, et des glandes flagelliformes élaborant les fils qui la soutiennent.
Il parait très probable que ce manque de glandes soit un caractère dérivé et non pas primitif.
Selon World Spider Catalog (version 20.5, 28/10/2019)[10] :
Cette espèce a été décrite sous le protonyme Aranea citricola par Forsskål en 1775.
La sous-espèce Cyrtophora citricola abessinensis[11] a été placée en synonymie avec Cyrtophora citricola citricola par Nentwig, Blick, Gloor, Jäger et Kropf en 2019[12].
Cyrtophora citricola (flèche) et chapelet de 8 cocons. Mahé, Seychelles.
Cyrtophora citricola (flèche) sous son chapelet de 3 cocons. Ténérife, Canaries.
Cyrtophora citricola sur sa toile à mailles carrées. Ténérife, Canaries
Face ventrale d'une Cyrtophora citricola sur les collines niçoises (France).
Gros plan sur son abdomen et ses tubercules. Nice, Alpes-Maritimes, 2017.
Le même individu ♀ avec ses nouveau-nés dans la toile.
Cyrtophora citricola, l'Épeire de l'Opuntia, est une espèce d'araignées aranéomorphes de la famille des Araneidae.
Cyrtophora citricola adalah spesies laba-laba yang tergolong famili Araneidae. Spesies ini juga merupakan bagian dari ordo Araneae. Nama ilmiah dari spesies ini pertama kali diterbitkan pada tahun 1775 oleh Forsskål.
Laba-laba ini biasanya banyak ditemui di Old World, Hispaniola, Kosta Rika, Kolombia.
Cyrtophora citricola adalah spesies laba-laba yang tergolong famili Araneidae. Spesies ini juga merupakan bagian dari ordo Araneae. Nama ilmiah dari spesies ini pertama kali diterbitkan pada tahun 1775 oleh Forsskål.
Laba-laba ini biasanya banyak ditemui di Old World, Hispaniola, Kosta Rika, Kolombia.
De visnetspin[1] (Cyrtophora citricola) is een spinnensoort uit de familie wielwebspinnen die in de warmere delen van Europa, Azië, Afrika, Midden-Amerika, Colombia en Australië.
In tegenstelling tot andere wielwebspinnen, maakt deze spin een horizontaal web met een kegel in het midden. Het zwart-witte patroon kan zeer verschillend zijn. Soms zijn ze bruin. De spinnen lijken op dode bladeren, vaak verbergen ze zich in een blad dat in hun web is gevallen. De vrouwtjes worden 10 mm groot, de mannetjes maar 3 mm. Vrouwtjes bouwen hun web vaak vlak bij andere, soms honderden, soortgenoten.
Cyrtophora citricola é uma aranha pertencente a família Araneidae. Ocorre nas partes mais quentes da Europa, Ásia e África, mas também na Austrália, Costa Rica, Hispaniola e Colômbia. Agora também pode ser encontrada em outras partes, como o Brasil e a Flórida, onde foi encontrada pela primeira vez em 2000.[1][2]
Cyrtophora citricola é uma aranha pertencente a família Araneidae. Ocorre nas partes mais quentes da Europa, Ásia e África, mas também na Austrália, Costa Rica, Hispaniola e Colômbia. Agora também pode ser encontrada em outras partes, como o Brasil e a Flórida, onde foi encontrada pela primeira vez em 2000.
Aranea citricola
Epeira opuntiae
Epeira cacti-opuntiae
Epeira citricola
Epeira emarginata
Epeira flava
Epeira purpurea
Epeira dorsuosa
Cyrtophora sculptilis
Cyrtophora opuntiae
Epeira cajetana
Araneus citricola
Cyrtophora dorsuosa
Wikimedia Commons'ta Cyrtophora citricola ile ilgili çoklu ortam belgeleri bulunur. 
Wikispecies'te Cyrtophora citricola ile ilgili detaylı taksonomi bilgileri bulunur. Cyrtophora citricola, Araneidae familyasından, Eski Dünya'nın sıcak kısımlarında yaşayan ve daha sonra Avustralya ile Yeni Dünya'ya da yayılan bir örümcek türü. 2004 yılında Brezilya'da[1] da görülmüştür. Türkiye'de[2] 2012 yılında Muğla ve Antalya illerinde tespit edilmiştir.
İlk kez 1775 yılında İsveçli kâşif, oryantalist ve doğa tarihi uzmanı Peter Forsskål (1732-1763) tarafından Aranea citricola adıyla tanımlanan tür 1864 yılında Simon tarafından Cyrtophora citricola adıyla revize edilmiştir.
Karapaks genelde kahverengi olsa da, siyahımsı kahverengi ya da sarımsı kahverengi renk çeşitlenmeleri de görülür. Opisthosoma (cephalothorax) posterior kenarına doğru sarımsıdır[2].
Sıcak bölgelerde görülür. Ortada bir koni oluşturan ve birçok destek hatları ile tutturulan yatay ağ örerler. Ağ yapışkan değildir
Ergin erkekler ağ örmezler ve yemekten kesilirler. Çiftleştikten kısa bir süre sonra da ölürler. Dişiler yavruları korumak için erkeklerden daha uzun yaşasalar da bazen yavrular yumurtadan çıkmadan önce de ölebilirler. Bir dişi en fazla on yumurta kesesi üretebilir. Yassı eliptik yumurta keseleri 20 mm uzunluğunda olup yeşilimsiden mavimsi renge kadar değişkenlik gösterir
Cinsinin Türkiye'deki tek türüdür ve 2012 yılında Muğla ve Antalya illerinde tespit edilmiştir[2].
4 alt türden oluşur[3]:
Cyrtophora citricola, Araneidae familyasından, Eski Dünya'nın sıcak kısımlarında yaşayan ve daha sonra Avustralya ile Yeni Dünya'ya da yayılan bir örümcek türü. 2004 yılında Brezilya'da da görülmüştür. Türkiye'de 2012 yılında Muğla ve Antalya illerinde tespit edilmiştir.
Cyrtophora citricola là một loài nhện trong họ Araneidae.[1] Chúng thường phân bố ở các nơi ấm hơn ở châu Âu, châu Á và châu Phi, nhưng cũng hiện diện ở Úc, Costa Rica, Hispaniola và Colombia. Nó có thể bây giờ cũng được tìm thấy trong các khu vực khác, chẳng hạn như Florida, nơi mà lần đầu tiên được tìm thấy vào năm 2000.
Loài nhện này không đan lưới. Lưới ngang của chúng tạo thành một hình nón ở giữa, với nhiều đường dây hỗ trợ nắm giữ nó. Lưới không dính, và xoắn ốc.
Cyrtophora citricola là một loài nhện trong họ Araneidae. Chúng thường phân bố ở các nơi ấm hơn ở châu Âu, châu Á và châu Phi, nhưng cũng hiện diện ở Úc, Costa Rica, Hispaniola và Colombia. Nó có thể bây giờ cũng được tìm thấy trong các khu vực khác, chẳng hạn như Florida, nơi mà lần đầu tiên được tìm thấy vào năm 2000.
Loài nhện này không đan lưới. Lưới ngang của chúng tạo thành một hình nón ở giữa, với nhiều đường dây hỗ trợ nắm giữ nó. Lưới không dính, và xoắn ốc.
桔云斑蛛（学名：Cyrtophora citricola）为园蛛科云斑蛛属的动物。分布于地中海、非洲、亚洲南部、大洋洲以及中国大陆的四川、云南等地，主要栖息于树林、果园以及蔬菜地。[1]
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