Arctosa

Arctosa
A. cinerea
A. raptor with egg sac
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Lycosidae
Genus:	Arctosa C. L. Koch, 1847[1]
Type species
Aranea cinerea Fabricius, 1777
Species
See text
Diversity
165 species
Synonyms
Alopecosella Roewer, 1960 Arctosella Roewer, 1960 Arkalosula Roewer, 1960 Bonacosa Roewer, 1960 Leaena Simon, 1885 Leaenella Roewer, 1960 Tetrarctosa Roewer, 1960 Tricca Simon, 1889 Triccosta Roewer, 1960

Arctosa is a genus of wolf spiders first described by Carl Ludwig Koch in 1847, with more than 150 described species.[2]

Arctosa species are swift runners with relatively keen eyesight. Most species inhabit sandy places such as seashores or the banks of rivers and lakes, though some occupy heath or lichen habitats in high mountains. The principal body colors are gray, off-white, and tawny brown, matching their habitat.[3]

Arctosa species are medium-sized wolf spiders with a total length ranging from 4.5 to 16.0 mm.[3]

The carapace is broad and rather low, with relatively uniform height between the dorsal groove and posterior row of eyes. The carapace is usually glabrous or nearly so, colored yellow, off-white, or mottled with gray, yellow, or brown.[3]

The anterior row of eyes may be straight, somewhat procurved, or recurved, and varies in length relative to the middle row. The promargin of the fang furrow bears two or three teeth, while the retromargin has three teeth. The abdomen is usually pale and mottled similar to the carapace.[3]

The legs are usually pale and robust with dark bands, lightly scopulate. Tibia III bears two dorsal macrosetae or one plus a basal bristle, along with one to three retrolateral macrosetae. The trochanters are usually deeply notched at the tip on the ventral surface.[3]

The terminal apophysis of the male pedipalp is conspicuous and occurs in two parts or in one part of two different shapes and degrees of sclerotization. The embolus is straight or curved and largely hidden by the median apophysis in ventral view. The epigyne of females usually has a conspicuous atrium divided by a median septum and lacks a hood.[3]

Females usually attend their eggs in silk-lined burrows rather than carrying them about, and most species appear to be nocturnal.[3]

The numerous African Arctosa species require revision.[3]

As of October 2025[update], this genus includes 165 species and two subspecies.[2]

These species have articles on Wikipedia:

• 
  A. cinerea
• 
  female A. japonica
• 
  A. leopardus
• 
  A. perita with spiderlings
• 
  Arctosa sp.

• Citizen science observations for Arctosa at iNaturalist