Tan Jumping Spider
Platycryptus undatus
Salticidae (Jumping Spiders), Order Araneae
Physical Description
A dorso-ventrally flattened jumping spider with a robust, hairy body. The cephalothorax is broad and the abdomen is elongated and somewhat pointed at the rear. It lacks the bulbous appearance of many other jumpers, an adaptation for hugging tree bark.
Size Estimate
Body length 8-13 mm for females, males slightly smaller. Leg span roughly 15-20 mm. This appears to be an adult.
Coloration & Markings
Characterized by a mix of tan, gray, brown, and black. The most distinctive feature is the dark, undulating (undatus) or 'V-shaped' chevron pattern running down the center of the abdomen against a lighter background.
Web Type
The spider does not build webs for hunting. It is a visual, active hunter. It only uses silk to create thick, tubular 'pup tents' or retreats for molting, sleeping, and egg-laying.
Eye Arrangement
Typical Salticid pattern: 4 pairs of eyes. Two very large Anterior Median Eyes (AME) provide high-resolution binocular vision, flanked by smaller Anterior Lateral Eyes (ALE). Four other eyes are located on top of the cephalothorax.
Leg Characteristics
Stocky, powerful legs designed for jumping. The front legs are slightly more robust for grasping prey. Legs are covered in fine hairs (setae) and sensitive spines, often showing faint banding.
Venom & Safety Information
Venom Information
Possesses a mild venom used to immobilize small insects. The venom is not considered dangerous to humans; it is designed to act on the nervous system of much smaller organisms.
Medical Significance
Low medical significance. Bites are extremely rare and usually only occur if the spider is squeezed. Symptoms are typically less severe than a bee sting, involving minor localized swelling or itching.
Safety Recommendations
Harmless and beneficial; no action is necessary. If relocation is desired, they can be easily coaxed into a cup and moved outside to a tree or fence.
Habitat & Behavior
Habitat & Range
Common across North America, particularly the eastern United States and parts of Canada. They are most frequently found on vertical surfaces like tree trunks, fences, and the siding of houses.
Behavior & Temperament
Highly intelligent and inquisitive. They use their keen eyesight to track movement. When approached, they often turn to face the observer. They are active during the day (diurnal) and generally very calm and non-aggressive toward humans.
Diet & Prey
Primary diet consists of flies, crickets, and other small insects. They stalk their prey like a cat, then leap several times their body length to deliver a precision bite.
Seasonal Activity
Most active from spring through autumn. In winter, they overwinter in silken retreats under bark or in crevices of buildings.
Description
The Tan Jumping Spider is a charming and helpful resident of many North American gardens and homes. Unlike many spiders that hide in dark corners, this species is often seen out in the sun, patrolling walls and trees for pests. Their large eyes and curious behavior make them a favorite among macro-photographers and nature enthusiasts.
Key Features
Flattened body profile; grey/tan coloration; distinct dark wavy pattern (chevrons) on the dorsal abdomen; large 'headlight' eyes.
Similar Species
May be confused with Menemerus bivittatus (Gray Wall Jumper), which has more distinct lateral stripes, or other Platycryptus species like P. californicus in the West.
Life Cycle
Females lay eggs inside a silken retreat during early summer. They exhibit basic maternal care by guarding the egg sac until the spiderlings emerge. Lifespan is approximately one to two years.
Ecological Importance
Critical natural pest controllers, especially around human dwellings where they consume flies, gnats, and mosquitoes without the use of messy webs.
Conservation Status
Not evaluated by the IUCN, but considered common and stable throughout its range.
Interesting Facts
They are capable of jumping 10 to 50 times their body length. Before jumping, they always anchor a silk 'dragline' to their starting point, acting as a safety tether in case they miss the target.
Photography Tips
Focus on the anterior median eyes to capture the spider's 'personality.' Use a high shutter speed to freeze their quick movements and look for them on vertical surfaces in bright, indirect light.
Identified: 2026-06-10T15:54:29.467551