Wolf Spider, Swamp Wolf Spider
Tigrosa helluo
Lycosidae (Wolf Spiders), Order Araneae. Characterized by excellent vision and unique maternal care.
Physical Description
A robust, hairy spider with a stout cephalothorax and an oval-shaped abdomen. In this specimen, the abdomen is obscured by hundreds of spiderlings. They have a characteristic dorsal median stripe on the cephalothorax.
Size Estimate
Body length 15-25mm; Leg span 50-70mm. This is an adult female.
Coloration & Markings
Deep brown to grayish-black base. Features a prominent pale yellow or tan median stripe running down the center of the cephalothorax. The legs are mottled with darker bands.
Web Type
Non-web building. Wolf spiders are wandering hunters that do not use webs to catch prey, though they may line burrows with silk.
Eye Arrangement
Three rows: 4 small anterior eyes, 2 very large posterior median eyes (prominent in this family), and 2 medium posterior lateral eyes.
Leg Characteristics
Thick, powerful legs designed for running. They are covered in sensory hairs (setae) and small spines (macrosetae). Notable for their ability to walk on water surfaces using surface tension.
Venom & Safety Information
Venom Information
Possesses a protein-based venom used to paralyze insects. It is not considered toxic to humans.
Medical Significance
Low medical significance. Bites are rare and typically result only in localized pain, redness, or minor swelling similar to a bee sting.
Safety Recommendations
If found in a pool, use a skimmer to gently relocate her to nearby vegetation. Avoid squashing or hitting her, as this will cause the hundreds of spiderlings to scatter.
Habitat & Behavior
Habitat & Range
Common across North America, particularly in the Eastern and Central United States. Prefer moist areas, gardens, woodlands, and the edges of ponds or pools.
Behavior & Temperament
Diurnal and nocturnal active hunters. They are generally shy and will flee when disturbed. They are not aggressive toward humans but can be defensive if handled.
Diet & Prey
Insects including crickets, beetles, and flies, as well as other spiders. They use their speed and strength to overpower prey.
Seasonal Activity
Most active from late spring through autumn. Females carrying young are frequently spotted in mid-to-late summer.
Description
An impressive example of a female Wolf Spider exhibiting maternal care. This wandering hunter is often seen near water sources, visible here skimming across a pool surface. She is carrying her entire current generation of offspring on her abdomen for protection.
Key Features
Large size, prominent median stripe on cephalothorax, and the distinct behavior of carrying spiderlings on the back.
Similar Species
Tigrosa aspersa (Forest Wolf Spider) which is usually larger and has a different venter pattern, or Dolomedes (Fishing Spiders) which lack the specific eye arrangement of Lycosidae.
Life Cycle
Unique maternal care: females carry egg sacs attached to spinnerets. After hatching, spiderlings (visible here) climb onto the mother's back and ride there for several weeks until they are large enough to be independent.
Ecological Importance
Vital for natural pest control, consuming high volumes of agricultural and garden pests.
Conservation Status
Not evaluated by IUCN, but widespread and common with stable population trends.
Interesting Facts
Wolf spiders have reflective eyes due to a tapetum lucidum; they will glow like tiny diamonds when hit by a flashlight beam at night.
Photography Tips
Focus on the cephalothorax to capture the stripe and eye arrangement. High-speed shutter is necessary if she is moving across water.
Identified: 2026-06-24T10:45:46.637426