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Verrucosa arenata are also known as triangulate orb weavers,arrowhead spiders, or arrowhead orbweaver. Verrucosa arenata are the one of the only known large orb web spiders that sits facing upwards in the web. Usually, orbweavers have a bulbous abdomen, however V. arenata abdomens are shaped like the tip of an arrow: triangular and pointy. The females triangular abdomen are either white or yellow. The yellow morphs were seen to be more successful in attracting prey. Additionally, these arrowhead spiders use reeling behavior in order to capture their prey as their webs are stronger than most other orb weavers. The genus name Verrucosa means "warty" and refers to the small wartlike bumps on the abdomen of this spider. The specific epithet arenata derives from Latin "arena", meaning "sand".

Description
Verrucosa arenata are large spiders where the females weigh 0.05-0.46 g and their body length is 7-14 mm. This species is sexually dimorphic with females that are larger than males as male body length is around 4-6 mm. Verrucosa arenataare polychromatic and their abdomen color ranges from white to yellow. Some smaller, vein-like markings on this area are red. 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's are 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. Verrucosa arenata are diurnal and their webs are usually non-functional due to insect damage by midday, and the spider ends the night in a retreat.

Distribution and Habitat
Verrucosa arenata are found across Nother America. V.arenata are found in the understory on the edges of vegetation and experience direct sunlight. These arrowhead spiders are most commonly in woods in late summer and early fall. They are also often seen in yards and other places where trees and bushes create appropriate open areas for them to spin circular webs. Their webs can be found at the edges of vegetation in different types of plantation and even in urban parks and gardens.

Webs
Verrucosa arenata are orb-web spiders and their webs are nearly invisible to their insect prey. Unlike most orb-web spiders that face downwards in the web, Verrucosa arenata face upwards in the web. Their webs are down-biased asymmetric. Some benefits to this upward orientation is that V. arenata can build top-biased webs that likely lead to more efficient prey capture, more prey interceptions, can catch insects faster in the upper part of the webs. Verrucosa arenata webs are generally elliptical with an elongated hub area. The spiders are then oriented so that their cephalothorax is facing upwards. During prey capture, Verrucosa arenata ran towards the prey, stopped and then pulled the prey towards itself when running downwards. The running rates between upward running and downward running spiders did not differ, but the time it takes to capture prey depended on the weight of the spider where heavier spiders ran slower upwards and ran downwards faster. V. arenata usually take down their webs or they 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.

Prey
Verrucosa arenata typically capture insects by trapping them in the sticky strands of their webs. They will 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. Their most common prey is dipterans and hymenopterans.

Reeling Behavior
Verrucosa arenata pluck the web which means that the spider tugs at the radial threads with their frontal legs in order to locate the prey or induce further prey movements. This plucking motion is associated with the spider locating the prey and possibly for further entanglement of the prey. 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 and this behavior can differ based on the weight of the prey. Spiders approached heavier prey more slowly than light 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 since their 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.

Color Polymorphism
Verrucosa arenata show color variation in the triangular pattern on the dorsal part of the abdomen. It is usually either white or yellow and it can reflect light in the UV part of the 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 spider than the yellow spider. 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 one (yellow) attracts more prey at the potential cost of attracting more predators.

Thermoregulation
Verrucosa arenata actively thermoregulate 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 which suggests that V. arenata are achieving their thermoregulatory status through behavioral or physiological means rather than through pigments. However, white morphs have a higher overall reflectance which means that they 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.