Turf Running Spider

Appearance

Males of this species are approximately 3.5-5.0 mm long, and females are about 5.3 mm long. Body color is variable, mostly in shades of brown or yellow. Spots are also a common body pattern. Males tend to have more spots than females. Legs are usually yellowish brown or grey. Some members of the species also have spots on their legs. Males of the species have a noticeably asymmetric sperm duct. Male pedipalps contain nerve tissue and a sensory organ.

Habitat

"Philodromus cespitum" is a foliage-dweller, and is the dominant species found in Central European fruit orchards. It is more highly concentrated in orchard centers than edges. Larger individuals are found in the center and smaller individuals are found around the edges. This species is also found in cotton fields. Its distribution extends across North America, Europe, North Africa, Turkey, Russia, Kazakhstan, China, Korea, and Japan. Adult females are most commonly observed in June and July. Spiderlings are present year-round but are most abundant from August to October.

Reproduction

Females lay around 250 eggs and construct five to seven egg cocoons. Females build egg cocoons during oviposition. The number of eggs laid is not affected by changes in temperature. The number of larvae that hatch decreases after the third egg cocoon built.

The time from oviposition to hatching is 20 days at 15 °C and 10 days at 24 °C. The developmental time of nymph-stages is about 430 days. Developmental time is longer for females than for males regardless of temperature.

Females of this species tend to live longer than males. The lifespan of both sexes in a laboratory setting is shorter when housed together than when individually housed.

Food

"Philodromus cespitum" are diurnal hunters. They capture their prey mainly through ambush. They feed on insects and spiders found in fruit orchards, such as aphids, the pest "Cacopsylla pyri", and "Theridion" spiders. They sometimes engage in intraguild predation, in which they feed on competitor species as well as smaller prey. A diet of both competitor spiders and aphids increases the overall fitness of "P. cespitum." However, since the costs are high due to retaliation and risk of injury from the competitor spider, intraguild predation does not often occur.

Foraging aggressiveness in "P. cespitum" can sometimes lead to overkilling, where the organism kills more prey than it can consume. Aggressiveness in this species is positively correlated with size and capture success. Aggressiveness also significantly increases the probability of intraguild predation.