Tan Jumping Spider, Familiar Jumping Spider
Platycryptus undatus
Salticidae (Jumping Spiders), Order Araneae
Physical Description
A stout, flattened jumping spider with a hairy body. The abdomen is elongated and slightly pointed at the rear, while the cephalothorax is broad and powerful. They appear 'fuzzy' due to a dense covering of short setae.
Size Estimate
Estimated body length 8-13mm for females, males slightly smaller (5-10mm). Leg span is relatively short and compact.
Coloration & Markings
Characterized by a complex mottled pattern of grey, tan, and brown. The most diagnostic feature is the dark, undulating 'V' or 'chevron' shaped markings along the length of the abdomen, bordered by lighter grey.
Web Type
Does not build hunting webs. They are active hunters. They do construct small, silk, tube-like retreats or 'pup-tents' for molting, sleeping, and protection of egg sacs.
Eye Arrangement
Typical Salticid pattern: 4 pairs of eyes. The anterior median eyes are very large and forward-facing, providing excellent binocular vision and depth perception, flanked by smaller anterior lateral eyes.
Leg Characteristics
Stocky, powerful legs used for jumping. Front legs are slightly heavier for grasping prey. Legs are generally mottled grey and brown with faint banding and covered in fine hairs.
Venom & Safety Information
Venom Information
Possesses a mild venom used to immobilize small insect prey. The venom is not considered toxic to humans.
Medical Significance
Harmless. Bites are extremely rare and typically only occur if the spider is pinched or handled roughly. Symptoms are usually less severe than a bee sting, involving minor localized redness or itching.
Safety Recommendations
No special precautions needed. If found indoors, they can be easily relocated using a cup and a piece of paper. They are beneficial to have around and pose no threat to pets or children.
Habitat & Behavior
Habitat & Range
Found across North America, particularly the Eastern and Central United States. Common on vertical surfaces like tree bark, fence posts, and the exterior walls of buildings.
Behavior & Temperament
Highly alert, curious, and active diurnal hunters. They possess excellent eyesight and will often turn to 'track' a moving person. They are non-aggressive toward humans and generally prefer to jump away when disturbed.
Diet & Prey
Generalist predators of small arthropods, including flies, mosquitoes, moths, and other spiders. They hunt by stalking and then pouncing on prey from a distance using an anchored silk dragline.
Seasonal Activity
Most active from spring through autumn. They overwinter as adults or sub-adults in silk-lined crevices or under bark.
Description
The Tan Jumping Spider is a charismatic neighborhood resident often seen patrolling sunlit walls and fences. Its flattened body allows it to squeeze into tight crevices, while its exceptional vision makes it one of the most effective miniature hunters in the garden.
Key Features
Flattened body profile; grey/tan mottled coloration; distinct dark undulating chevron pattern on the abdomen; large, forward-facing primary eyes.
Similar Species
Menemerus semilimbatus and Platycryptus californicus. It is distinguished from the former by the specific abdominal pattern and from the latter by geographic range (East vs. West Coast).
Life Cycle
Females lay eggs in silk retreats, often under bark or in crevices during the summer. They exhibit a degree of maternal care, guarding the egg sac until the spiderlings emerge. Lifespan is approximately one to two years.
Ecological Importance
Significant natural pest control, consuming large quantities of nuisance insects around homes and in gardens without the need for chemical intervention.
Conservation Status
Not evaluated by IUCN; generally considered common and stable throughout its range.
Interesting Facts
Despite their small size, they have vision comparable to some vertebrates. They use a silk 'safety line' before every jump to ensure they don't fall if they miss their target.
Photography Tips
Get low and level with the spider's face to capture the large primary eyes. Use a fast shutter speed to account for their sudden, jerky movements. Macro lenses are ideal for capturing the intricate hair textures.
Identified: 2026-06-15T01:34:13.862328