Tetragnatha versicolor

Appearance

''T. versicolor'' is generally a very small spider with males being slightly smaller than females. Males will average around 5 mm in length and 1.3 mm in width while females will average around 6.5 mm in length and 1.5 mm in width.

The carapace of male ''T. versicolor'' will typically be colored dark yellow or pale orange with markings radiating dorsally. The male's lateral eyes are closer together than their median eyes. The distance between median and lateral eyes is rarely the same.

Like the carapace, the legs are colored dark yellow or pale orange with a silver abdomen dorsally along the sides. The male's conductor has a thick rounded tip and a small point near the base of the structure. Females follow the same coloration patterns and eye spacing but have different reproductive structures. Their epigynum is short, broad, and concave and found on the posterior. The spermatheca contains an anterior and posterior end It appears large and bulbous.

Naming

''T. versicolor'' can be differentiated from other species in the genus by the distinct separation of the anterior/posterior eyes and the appearance of the reproductive organs. In addition, ''T. viridis'' looks very similar and can be distinguished from ''T. versicolor'' by the above mentioned criteria as well as the long macrosetae on the leg tibiae.

Distribution

''T. versicolor'' can be found throughout most regions of North America. In the United States, this spider is heavily concentrated in the northeast and the west coast, from California to Washington. There have been sightings in Alaska as well. ''T. versicolor'' has been documented throughout Canada and very scarcely in Mexico, Central America, and even Cuba.

Behavior

Egg sacs of ''T. versicolor'' are laid in May, June, and July. Mating can occur many times throughout a single lifespan. The egg sacs are each around 5-6 mm in diameter and are of greenish/whitish color. Each egg sac may contain as many as 103 eggs, each around 0.66 mm in diameter. Mature spiders can be found from April to September. It is unclear how long ''T. versicolor'' can live, but it is speculated that they can live at least a year. Once spiderlings hatch, they will molt several times before reaching maturity.''T. versicolor'' has very poor vision, but is sensitive to vibrations and touch. During mating, ''T. versicolor'' will vibrate their webs to communicate.

Habitat

''T. versicolor'' is a habitat generalist, indicating it is a species that mainly responds to spatial cues and dispersal processes instead of environmental processes and cues from other individuals. Unlike its relatives ''T. viridis'', ''T. straminea'', and ''T. elongata'', it can live in areas ranging widely in elevation and vegetation type. While they can be found in places like wetlands, spruce forests, red oak forests, grasslands, etc., ''T. versicolor'' tends to prefer dryer environments and are therefore rarely found close to aquatic habitats. Trees and shrubs are the natural home for these spiders. If present in marshy areas, ''T. versicolor'' will usually be near herbaceous vegetation.

Reproduction

Egg sacs of ''T. versicolor'' are laid in May, June, and July. Mating can occur many times throughout a single lifespan. The egg sacs are each around 5-6 mm in diameter and are of greenish/whitish color. Each egg sac may contain as many as 103 eggs, each around 0.66 mm in diameter. Mature spiders can be found from April to September. It is unclear how long ''T. versicolor'' can live, but it is speculated that they can live at least a year. Once spiderlings hatch, they will molt several times before reaching maturity.

Food

Spiders of the ''Tetragnathidae'' family feed mainly on small flying insects that are caught in their wheel-shaped web. In addition to insects, they will also prey upon arthropods that happen to get caught in their web. Known predators of the ''T. versicolor'' include birds, lizards, shrews, salamanders, and jumping spiders. ''T. versicolor'' are nocturnal, and are active only at night so they can avoid predators. During the day, they will line their bodies on twigs so they can camouflage themselves. Usually, ''T. versicolor'' will use thin branches so that heavier predators have a harder time reaching them.

Interestingly, venom composition of ''T. versicolor'' is related to the spider's diet. Female ''T. versicolor'' living in different regions consume different insects and this varied consumption of prey leads to differential expression of venom-producing genes. There is also differential expression between the two sexes, with males more likely to overexpress this venom-related gene than females - an example of sexual dimorphism in these spiders.''T. versicolor'' is very sedentary in their hunting strategy. As an orb weaver spider, ''T. versicolor'' will stay in one place most of the time to catch their prey. They often sit in the center of their webs or wait on nearby twigs or branches for prey to get caught up in their web. A mature male ''T. versicolor'' a may also wander to catch prey, whereas a female almost always remains sedentary. The sexual dimorphic expression of the venom-producing genes explains this behavior - males are more likely to overexpress the venom gene than females, which would be useful given that males are more susceptible to predation and attacks if they wander to hunt for prey.