Lobo da Grama, Grass Wolf Spider, South American Wolf Spider
Lycosa erythrognatha (probable)
Lycosidae (Wolf Spiders), Order Araneae
Physical Description
A robust, ground-dwelling spider with a distinct oval cephalothorax and a slightly elongated abdomen. The body is covered in fine, short hairs giving it a matte appearance. It features prominent spinnerets at the rear of the abdomen.
Size Estimate
Body length 20-30mm; leg span approximately 50-70mm. This appears to be a sub-adult or adult specimen.
Coloration & Markings
Greyish-brown base coloration. The cephalothorax features a distinct light-colored longitudinal stripe flanked by darker bands. The abdomen shows a dark, spear-shaped cardiac mark followed by a series of faint chevrons. In this species, the chelicerae (mouthparts) often show reddish-orange hairs, though not clearly visible here.
Web Type
This is a hunting spider that does not build a capture web. It may construct a silk-lined retreat or burrow in soil or under debris.
Eye Arrangement
Distinctive wolf spider pattern: four small eyes in a bottom row, two very large eyes in a middle row (Posterior Median Eyes), and two eyes in a top row (Posterior Lateral Eyes) set further back.
Leg Characteristics
Long, thick, and powerful legs designed for sprinting. They are covered in sensory hairs and macrosetae (spines), typically showing faint banding or mottling.
Venom & Safety Information
Venom Information
Contains neurotoxic and proteolytic components. While painful, it is generally considered mildly to moderately toxic to humans, significantly less dangerous than Phoneutria (wandering spiders).
Medical Significance
Low to Moderate. Bites cause localized pain, swelling, and redness. Systemic reactions are rare but can include nausea. Treatment is usually symptomatic (ice and pain relief); seek medical attention if necrosis or severe allergic reactions occur.
Safety Recommendations
If found indoors, relocate using the 'cup and card' method. Wear gloves when gardening in areas they frequent. Do not handle with bare hands.
Habitat & Behavior
Habitat & Range
Primarily South America (Brazil, Uruguay, Argentina, Paraguay). Habitats include grasslands, gardens, pastures, and occasionally urban indoor environments.
Behavior & Temperament
Active cursorial hunter. Diurnal or crepuscular. Generally non-aggressive toward humans, preferring to flee, but may bite if handled or provoked. They have excellent eyesight and are very fast.
Diet & Prey
Generalist predator feeding on insects like crickets, cockroaches, and grasshoppers, as well as smaller spiders. They use speed and strength rather than webs to overpower prey.
Seasonal Activity
Active year-round in tropical climates, with peak visibility during the warmer, wetter months which coincide with mating seasons.
Description
The Grass Wolf Spider is a common sight in South American landscapes. A master of camouflage among dry leaves and soil, this agile hunter relies on its keen eyesight and explosive speed to secure meals, playing a vital role in balancing insect populations.
Key Features
Longitudinal stripes on the carapace, large Posterior Median Eyes, and a dark cardiac mark on the abdomen.
Similar Species
Often confused with the Brazilian Wandering Spider (Phoneutria), which has a more 'flat' eye arrangement and different leg posture, or Grass Spiders (Agelenidae), which have much longer spinnerets and build sheet webs.
Life Cycle
Females carry their egg sacs attached to their spinnerets. Upon hatching, the spiderlings climb onto the mother's back and are carried for several days before dispersing via ballooning or wandering.
Ecological Importance
Significant natural pest controller, consuming large numbers of agricultural and household pests.
Conservation Status
Not evaluated by IUCN; generally considered common and widespread, though threatened by heavy pesticide use in urban and agricultural areas.
Interesting Facts
The genus name Lycosa comes from the Greek word for 'wolf'. These spiders are among the few that exhibit significant maternal care by carrying their young on their backs.
Photography Tips
Focus on the eyes to capture the characteristic Lycosid arrangement. Use a lateral or top-down angle to highlight the stripes on the cephalothorax.
Identified: 2026-07-01T03:32:05.032844