Verrucosa arenata

Last updated

Verrucosa arenata
Arrowhead Spider - Verrucosa arenata, Julie Metz Wetlands, Woodbridge, Virginia - 03.jpg
Female V. arenata from Virginia
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Araneidae
Genus: Verrucosa
Species:
V. arenata
Binomial name
Verrucosa arenata
(Walckenaer, 1842) [1]
Synonyms [1]
  • Epeira mexicanaLucas, 1833
  • Epeira arenataWalckenaer, 1841
  • Epeira verrucosaHentz, 1850
  • Acanthepeira verrucosaMarx, 1883
  • Verrucosa arenataMcCook, 1888
  • Mahadeva verrucosaKeyserling, 1892
  • Verrucosa arenataMcCook, 1894
  • Araneus mexicanusSimon, 1895
  • Epeira verrucosaEmerton, 1902
  • Verrucosa arenataF. O. Pickard-Cambridge, 1904
  • Araneus arenatusPetrunkevitch, 1911
  • Araneus aequiangulusFranganillo, 1930
  • Araneus aequiangulus ochraceusFranganillo, 1930
  • Verrucosa arenataPetrunkevitch, 1930
  • Verrucosa arenataLevi, 1976
  • Verrucosa arenataCoddington, 1990
  • Verrucosa arenataScharff & Coddington, 1997
  • Verrucosa arenataLevi, 2002
  • Verrucosa arenataLise, Kesster & da Silva, 2015

Verrucosa arenata, also known as the triangle orb weaver, arrowhead spider, and arrowhead orbweaver, is a species of orb-weaver spider found across North America. [2] It is one of the few known large orb-weaver spiders that sits facing upwards in its web. [3] Unlike most orb-weavers, which have bulbous abdomens, V. arenata has an abdomen that is pointy and triangular, shaped like the tip of an arrow. [4] In females, the abdomen is colored white or yellow. [5] Additionally, V. arenata uses reeling behavior in order to capture its prey, as its webs are stronger than that of most other orb weavers. The genus name Verrucosa means "warty" in Latin, referring to the small wartlike bumps on the spider's abdomen, [2] while the specific epithet arenata derives from Latin arena, meaning "sand".

Contents

Distribution and habitat

Verrucosa arenata are found across a variety of urban and rural habitats in North America, in areas with trees and bushes to spin their webs. These may include plantations, urban parks, gardens, yards, or woods. They are typically found in late summer and early fall, living in the understory, along open, humid areas where they may experience direct sunlight. [2] [5] [6]

Description

Verrucosa arenata are large spiders. Females weigh 0.05–0.46 g and their body length is 7–14 mm. [7] This species is sexually dimorphic, as females are larger than males. Male body length ranges from 4 to 6 mm. V. arenata are polychromatic and their abdomen color ranges from white to yellow. [6] Some smaller, vein-like markings on the abdominal area are red. [4] Females can have black, brown, or rusty red colored legs and carapace. The head is small compared to this spider's triangular abdomen. Their abdomen is completely covered with a triangle of color, usually yellow or white. Males are smaller and lack the characteristic triangle on their abdomen. The male arrowhead spiders are rarely seen unless they are mating or courting a female spider in their web. [2] V. arenata are diurnal. Their webs are usually non-functional by midday due to insect damage and the spider ends the night in a retreat. [3]

Color polymorphism

V. arenata show color variation in the triangular pattern on the dorsal part of the abdomen. This part of the abdomen is usually either white or yellow. It can reflect light in the UV part of the electromagnetic spectrum. Yellow arrowhead spiders showed higher chromatic contrast while white spiders showed higher achromatic contrast. White spiders have been observed to be more abundant during the breeding season and have a better body condition than yellow spiders. However, yellow spiders are more successful at attracting prey. Additionally, a much higher amount of UV light is reflected by the white spiders than the yellow spiders. [5] Only at a close range does the effect of the different colors become apparent to prey and predators. There is a trade-off where the less visible morph (white) is dominant, but the more visible morph (yellow) attracts more prey at the potential cost of attracting more predators. [3]

Thermoregulation

V. arenata actively thermoregulates so that their body temperature is well below the ambient temperature. There is no difference in surface temperature for spiders with a yellow or white abdomen, suggesting that V. arenata are achieving their thermoregulatory status through behavioral or physiological means rather than through variation in pigmentation. However, white morphs have a higher overall reflectance. This means that white morphs could have an advantage in exploiting open habitats. V. arenata faces significant thermal constraints if they build their webs in exposed conditions, so the white morph has thermal advantages in these habitats since their pigmentation allows them to better withstand thermal stress. The white morphs could have a thermal advantage because they have lower absorption of short wave and visible radiation. [6]

Webs

Verrucosa arenata are orb-weaver spiders and their webs are nearly invisible to their insect prey. [3] V. arenata webs have a distinct architecture since it consists of a central hub without radial threads. Female V. arenata are usually observed to be in the center of the web since it is a good location for catching the most prey. In the web, the females usually have their heads up and the apex of the triangular mark pointing downwards. [8]

V. arenata is one of the few known large orb-weaver spiders that sits facing upwards in its web. Their webs are down-biased asymmetric. Some benefits to this upward orientation include V. arenata's ability to build top-biased webs that likely lead to more efficient prey capture, more prey interceptions, and faster catching of insects in the upper part of the webs. V. arenata webs are generally elliptical with an elongated hub area. The spiders are then oriented so that their cephalothorax is facing upwards.

V. arenata usually take down their webs. When they don't the webs are severely damaged by midday as a result of frequent rainfall. Additionally, their webs are made of tougher and stretchier silk strands in comparison to other orb web spiders. [9]

Prey capture techniques

During prey capture, V. arenata run towards the prey, stopping and then pulling the prey towards themselves when running downwards. The running rates between upward running and downward running spiders do not differ, but the time it takes to capture prey depends on the weight of the spider. Heavier spiders run slower upwards and run downwards faster. [7]

V. arenata pluck the web—meaning that the spider tugs at the radial threads of the web with their frontal legs—in order to locate the prey or induce further prey movements. Their ability to use the plucking motion is associated with the spider's location of prey and possibly for further entanglement of the prey in the web. After plucking, these spiders shake their whole body, known as 'bouncing', and then they will 'reel' the prey in by pulling on the radial thread as they approach the prey. V. arenata reel in prey from the bottom of their web towards themselves. Thus, this behavior can differ based on the weight of the prey. Spiders of this species approach heavier prey more slowly than they approach lighter prey. V. arenata are able to use this "reeling' method because its webs can withstand pulling at a much higher rate than most other spiders, as the web's silk strands are tougher and stretchier. Additionally, these arrowhead spiders usually remake their webs often, so web damage associated with reeling is not critical compared to the successful capture of prey. [9]

Diet

V. arenata typically capture insects by trapping them in the sticky strands of their webs. They deliver a bite of venom to subdue the prey and then digest the insides of the insect. They wait and then return to the insect in order to ingest its liquified contents. V. arenata specialize in eating tiny flying insects, like mosquitoes, since their webs have close spacing of circles. [2] Their most common prey is dipterans and hymenopterans. [5]

Related Research Articles

<span class="mw-page-title-main">Orb-weaver spider</span> Family of spiders

Orb-weaver spiders are members of the spider family Araneidae. They are the most common group of builders of spiral wheel-shaped webs often found in gardens, fields, and forests. The English word orb can mean "circular", hence the English name of the group. Araneids have eight similar eyes, hairy or spiny legs, and no stridulating organs.

<i>Araneus diadematus</i> Species of spider

The spider species Araneus diadematus is commonly called the European garden spider, diadem spider, orangie, cross spider and crowned orb weaver. It is sometimes called the pumpkin spider, although this name is also used for a different species, Araneus marmoreus. It is an orb-weaver spider found in Europe, where it is native, and North America, where it is introduced.

Australian garden orb weaver spider Species of spider

The Australian garden orb weaver spider is a very common species of spider with many variants in size, shape, and colour across the coastal regions of Australia. They have very large abdomens when well-fed and exhibit a tremendous colour-range from off-white through tan, brown to almost black. They have a roughly leaf-shaped pattern on the top of their abdomen with a complex outline that is darker than the surrounding area. There may also be several whitish spots or one or more stripes. The spiders' cephalothoraxes (heads) and proximal leg segments are usually darker, mostly reddish or reddish brown. They are able to change their colour with each moult to better match the background upon which they rest during the day.

<i>Austracantha</i> Genus of spiders

Austracantha is a genus of spider with a single species, Austracantha minax, commonly known as the jewel spider or the Christmas spider. It is a member of the family Araneidae and is endemic to Australia. They are relatively small spiders, reaching a maximum total body length of only around 12 mm (0.47 in) for females, and 5 mm (0.20 in) for males. Their abdomen has six distinctive projections ("spines") that makes them easy to identify. They are predominantly a shiny black, with variable white, yellow, and orange patterns. Melanistic forms also occur during autumn. They are facultatively gregarious, and can be found in large aggregations of overlapping orb webs. They feed on small flying insects that get entangled in their webs. They are harmless to humans, though the webs can be a nuisance for bushwalkers. They are most abundant during the summer months.

<i>Nephila</i> Genus of spiders

Nephila is a genus of araneomorph spiders noted for the impressive webs they weave. Nephila consists of numerous species found in warmer regions around the world. They are commonly called golden silk orb-weavers, golden orb-weavers, giant wood spiders, or banana spiders.

<i>Trichonephila clavipes</i> Species of spider native to the Americas

Trichonephila clavipes, commonly known as the golden silk orb-weaver, golden silk spider, or banana spider, is an orb-weaving spider species which inhabits forests and wooded areas ranging from the southern US to Argentina. In fact, it is the only species of the genus Trichonephila indigenous to both continental North and South America. Known for the golden color of their silk, the large size of their females, and their distinctive red-brown and yellow coloring, T. clavipes construct large, asymmetrical circular webs attached to trees and low shrubs in woods to catch small- and medium-size flying prey, mostly insects. They are excellent web-builders, producing and utilizing seven different types of silk, and they subdue their prey by injecting them with venom, as opposed to related species which immobilize their prey by wrapping them in silk first. They are not known to be aggressive towards humans, only biting out of self-defense if touched, and their relatively harmless venom has a low toxicity, posing little health concern to healthy human adults. Due to their prevalence in forests, T. clavipes may be encountered by hikers.

<i>Argiope aurantia</i> Species of spider

Argiope aurantia is a species of spider, commonly known as the yellow garden spider, black and yellow garden spider, golden garden spider, writing spider, zigzag spider, zipper spider, black and yellow argiope, corn spider, Steeler spider, or McKinley spider. The species was first described by Hippolyte Lucas in 1833. It is common to the contiguous United States, Hawaii, southern Canada, Mexico, and Central America. It has distinctive yellow and black markings on the abdomen and a mostly white cephalothorax. Its scientific Latin name translates to "gilded silver-face". The body length of males range from 5–9 mm (0.20–0.35 in); females range from 19–28 mm (0.75–1.10 in). These spiders may bite if disturbed or harassed, but the venom is harmless to non-allergic humans, roughly equivalent to a bumblebee sting in intensity.

<i>Theridion grallator</i> Species of spider in the family Theridiidae

Theridion grallator, also known as the Hawaiian happy-face spider, is a spider in the family Theridiidae that resides on the Hawaiian Islands. T. grallator obtains its vernacular name of "Hawaiian happy-face spider" from the unique patterns superimposed on its abdomen, specifically those that resemble a human smiling face. T. grallator is particularly notable because of its wide range of polymorphisms that may be studied to allow a better understanding of evolutionary mechanisms. In addition to the variety of color polymorphisms present, T. grallator demonstrates the interesting quality of diet-induced color change, in which its appearance temporarily changes as it metabolizes various food items.

<i>Zygiella x-notata</i> Species of spider

Zygiella x-notata, sometimes known as the missing sector orb weaver or the silver-sided sector spider, is a spider species in the family Araneidae. They are solitary spiders, residing in daily-spun orb webs. Z. x-notata is a member of the genus Zygiella, the orb-weaving spiders. The adult female is easily recognized by the characteristic leaf-like mark on her posterior opisthosoma, caudal to the yellow-brown cephalothorax.

<i>Nephila pilipes</i> Species of spider

Nephila pilipes is a species of golden orb-web spider. It resides all over countries in East and Southeast Asia as well as Oceania. It is commonly found in primary and secondary forests and gardens. Females are large and grow to a body size of 30–50 mm, with males growing to 5–6 mm. It is the second largest of the orb-weaving spiders apart from the recently discovered Nephila komaci. The first, second, and fourth pairs of legs of juvenile females have dense hairy brushes, but these brushes disappear as the spider matures.

<i>Gasteracantha fornicata</i> Species of spider

Gasteracantha fornicata is a species of spiny orb-weavers found in Queensland Australia. It is similar in shape to Austracantha minax which was originally described as Gasteracantha minax. It was described by Johan Christian Fabricius in 1775, the first Australian species of spider to be named and classified.

<i>Gasteracantha cancriformis</i> Species of spider

Gasteracantha cancriformis is a species of orb-weaver spider. It is widely distributed in the New World.

<i>Metepeira labyrinthea</i> Species of spider

Metepeira labyrinthea, the labyrinth orbweaver, is a spider, with thin legs and a round, bulbous abdomen It is a member of the genus Metepeira in the family Araneidae. The female’s length is 5.3 mm, its carapace 2.3 mm, abdomen 3.3 mm, and extended legs 18.4 mm. The carapace is brown or gray, and the abdomen is dark with a white pattern. The legs alternate pale brown and dark brown, and the sternum is dark brown with a longitudinal yellow mark. The male spider is three-quarters of the female’s length, or slightly larger, with a darker carapace and with greater contrast between dark and light areas of the legs. Metepeira are easily distinguished from other Araneidae by their light eye region, white median line on the sternum, relative length of the leg segments, small male palpus, weakly sclerotized epigyne and the special composite web.

<i>Cyrtophora citricola</i> Species of spider

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.

<i>Cyrtophora exanthematica</i> Species of spider

Cyrtophora exanthematica are tent spiders common in tropical Asia and Australia. They are commonly known as double-tailed tent spiders because of the pair of blunt projections at the end of their abdomens. They are harmless to humans.

<i>Araniella displicata</i> Species of spider

Araniella displicata, the sixspotted orbweaver, is a species of orb weaver in the spider family Araneidae. It is found in North America, Europe, a range from Russia to Kazakhstan, China, Korea, and Japan.

<i>Tetragnatha versicolor</i> Species of spider

Tetragnatha versicolor is a species of long-jawed orb weaver in the spider family Tetragnathidae. It is found throughout North America, Canada, Central America, and Cuba, but are most common in the United States. T. versicolor is heavily concentrated in New England and the west coast in states like California and Washington. T. versicolor is considered a habitat generalist, and can thrive in many different environments. While they can be found in places like Grasslands, Wetlands, Forests, etc., they prefer dryer areas like normal trees and shrubs. Unlike other spiders in the genus Tetragnatha, T. versicolor will rarely reside near aquatic environments. T. versicolor will typically be colored dark yellow or pale orange and average around 5 mm for males and 6.5 mm for females in length, which is very small for a spider. They are much longer than they are wide, making them very distinct. In addition, T. versicolor can be distinguished from other spiders in Tetragnatha by the distinct separation of the anterior/posterior eyes and the appearance of their reproductive organs. As an orb weaver spider, T. versicolor creates a web to hunt for prey. It will wait at night for prey to stumble into its web and use vibrational signals throughout the web to sense trapped prey. In terms of mating behavior, T. versicolor lacks a distinct courting ritual and will mate with any others in the proximity. Mating behavior is heavily affected by female mating history. In terms of interactions with humans, the bite of T. versicolor is venomous, but not known to cause significant harm.

<i>Mastophora hutchinsoni</i> Species of spider

Mastophora hutchinsoni, also known as the American bolas spider, is a species of orb weaver in the genus Mastophora. The genus is distributed extensively throughout various subtropical geographical areas including Australia, South Africa, Oriental Asia, and the Americas and is not found in Europe. The hunting behavior of adult female M. hutchinsoni is unusual because they are bolas spiders. They mimic moth pheromones to attract male moths, and female M. hutchinsoni have evolved to alter their chemical release to target different moths. They then capture their prey with a sticky drop on the end of a silk line, resembling a bolas.

<i>Argiope radon</i> Species of spider

Argiope radon is a species of orb web spider native to Australia. It is found in tropical areas of the Northern Territory, Western Australia and Queensland. It is commonly known as the Northern St Andrew's cross spider.

<i>Larinia jeskovi</i> Species of arachnid

Larinia jeskovi is a species of the family of orb weaver spiders and a part of the genus Larinia. It is distributed throughout the Americas, Africa, Australia, Europe, and Asia and commonly found in wet climes such as marshes, bogs, and rainforests. Larinia jeskovi have yellow bodies with stripes and range from 5.13-8.70 millimeters in body length. They build their webs on plants with a small height above small bodies of waters or wetlands. After sunset and before sunrise are the typical times they hunt and build their web. Males usually occupy a female's web instead of making their own. The mating behavior is noteworthy as male spiders often mutilate external female genitalia to reduce sperm competition while female spiders resort to sexual cannibalism to counter such mechanisms. The males also follow an elaborate courtship ritual to attract the female. The bite of Larinia jeskovi is not known to be of harm to humans.

References

  1. 1 2 "Verrucosa arenata". World Spider Catalog. Retrieved November 16, 2020.
  2. 1 2 3 4 5 "Arrowhead Spider (Triangle Orbweaver)". Missouri Department of Conservation. Retrieved November 16, 2020.
  3. 1 2 3 4 Rao, Dinesh; Castañeda-Barbosa, Ernesto; Nuñez-Beverido, Nicolas; Díaz-Fleischer, Francisco (September 2014). "Foraging benefits in a colour polymorphic Neotropical orb web spider" (PDF). Ethology. 121 (2): 187–195. doi:10.1111/eth.12330 . Retrieved November 16, 2020.
  4. 1 2 "Arrowhead Orb Weaver (Verrucosa arenata)". Insect Identification. Retrieved November 16, 2020.
  5. 1 2 3 4 Ajuria-Ibarra, Helena; Tapia-McClung, Horacio; Rao, Dinesh (May 2017). "Mapping the variation in spider body colouration from an insect perspective" (PDF). Evolutionary Ecology. 31: 663–681. doi:10.1007/s10682-017-9904-5 . Retrieved November 16, 2020.
  6. 1 2 3 Rao, Dinesh; Mendoza-Cuenca, Luis (July 2016). "The effect of colour polymorphism on thermoregulation in an orb web spider" (PDF). The Science of Nature. 103: 63. doi:10.1007/s00114-016-1388-6 . Retrieved November 14, 2020.
  7. 1 2 Rao, Dinesh; Ceballos Fernandez, Oscar; Castañeda-Barbosa, Ernesto; Díaz-Fleischer, Francisco (June 2011). "Reverse positional orientation in a neotropical orb-web spider, Verrucosa arenata" (PDF). Naturwissenschaften. 98: 699–703. doi:10.1007/s00114-011-0811-2 . Retrieved November 14, 2020.
  8. Bastos Francini, Ronaldo; Barril Dalla Pria, Alexandre (January 2015). "Architecture and disposition of orbicular webs of the spider Verrucosa arenata (Walckenaer 1841) on tropical rain forest edges in Southeastern, Brazil with notes on species Biology" (PDF). Journal of Entomology and Zoology Studies. 3 (1): 135–139. Retrieved November 19, 2020.
  9. 1 2 Rao, Dinesh; Tapia-McClung, Horacio; Narendra, Ajay (December 2019). "Reeling in the prey: fishing behaviour in an orb web spider". Journal of Experimental Biology. 222: jeb213751. doi: 10.1242/jeb.213751 . Retrieved November 16, 2020.

Commons-logo.svg Media related to Verrucosa arenata at Wikimedia Commons