Shore wolf spider
Arctosa littoralis
The shore wolf spider is one of the largest native wolf spiders and a highly specialized inhabitant of dynamic sand and gravel banks. Due to its light gray to brownish coloration, it is almost invisible on sandy substrates. It is predominantly nocturnal and hides during the day in self-dug burrows in the sand. The species is highly endangered in Central Europe due to the loss of natural river landscapes.
Details
Identification
Sand-colored base with dark, mottled patterns; legs distinctly dark-ringed; lacks dense hair on the cephalothorax.
Social behavior
Solitary and cannibalistic towards smaller conspecifics.
Diet
Predatory on ground-dwelling insects, other spiders, and small arthropods.
Hunting strategy
Active ambush hunter; prey is overwhelmed without a web by rapid striking.
Overwintering
Overwintering as an adult or subadult in deep burrows in the sandy soil.
Ecology
Ecological role
Important predator in pioneer communities of riparian ecosystems.
Natural predators
Birds, spider wasps (Pompilidae), and larger predatory beetles.
Competitor species
Other wolf spider species such as Pardosa species in the same habitat.
Ecosystem service
Regulation of insect populations in riparian areas.
Threats
Bank stabilization, river channelization, loss of sandbars due to lack of dynamics, and tourist trampling.
Scientific profile
Profile
Distinguishing features
A large wolf spider of the genus Arctosa. Characterized by the absence of distinct patterns in favor of camouflage. The legs are clearly dark-ringed or spotted. The eye arrangement is typical for Lycosidae: a front row of four small eyes, followed by two rows of two large eyes each. Generally slightly smaller and more finely spotted than Arctosa cinerea.