Tan Jumping Spider, Flatties
Platycryptus undatus
Salticidae (Jumping Spiders), Order Araneae. Key family characteristics include large forward-facing eyes providing exceptional stereoscopic vision, robust bodies adapted for jumping rather than web-weaving, and specialized adhesive pads (scopulae) on their feet for climbing smooth surfaces.
Physical Description
A compact, somewhat flattened body shape characteristic of the genus Platycryptus. The cephalothorax is broad and square-fronted, while the abdomen is elongated and oval. It has a slightly hairy or velvety texture that helps camouflage it against bark and weathered wood.
Size Estimate
Small to medium-sized jumping spider, with a body length typically ranging from 9 to 13 millimeters for females and slightly smaller for males. The leg span is proportional, fitting comfortably on small architectural fixtures.
Coloration & Markings
Predominantly brown, tan, and grey camouflage coloration with distinct wavy bands or chevrons across the abdomen and carapace. The coloration provides excellent crypsis on tree bark and rustic wooden or metallic surfaces.
Web Type
Does not build a web to catch prey. They are active hunters that utilize silk primarily to construct silken retreat sacs for molting, sleeping, or brooding eggs.
Eye Arrangement
Features the typical salticid eye pattern consisting of eight eyes arranged in three rows. The anterior median eyes (AME) are exceptionally large and provide high-resolution, forward-facing color vision.
Leg Characteristics
Stout, relatively short legs designed for powerful leaps rather than running. The legs show faint banding patterns and are equipped with dense claw tufts and scopulae for superior grip.
Venom & Safety Information
Venom Information
Contains mild venom used exclusively to subdue small insect prey. It is not toxic or harmful to humans.
Medical Significance
Completely harmless to humans. Bites are exceedingly rare, typically only occurring if the spider is squeezed or trapped against the skin, resulting in nothing more than a minor, temporary pinprick.
Safety Recommendations
No special precautions needed. If relocation is desired, gently guide the spider into a cup using a piece of paper and release it outdoors.
Habitat & Behavior
Habitat & Range
Found widely across eastern North America. Prefers vertical surfaces such as tree trunks, wooden fences, and the exterior walls of buildings where it basks in the sun and hunts.
Behavior & Temperament
Curious, highly alert, and entirely docile towards humans. They are diurnal hunters relying on incredible eyesight to stalk and pounce on insect prey, often turning to face observers.
Diet & Prey
Carnivorous, feeding on a wide variety of small insects such as flies, mosquitoes, aphids, and small beetles, captured via a sudden, calculated leap.
Seasonal Activity
Most active during the warm spring and summer months. They overwinter as juveniles or adults by sheltering in tight, protective silk cocoons tucked away under loose bark or siding.
Description
The Tan Jumping Spider is a charismatic and harmless visitor often found exploring outdoor surfaces. With its large, inquisitive eyes and remarkable agility, it serves as a wonderful example of intelligent invertebrate behavior.
Key Features
Flat body profile, grey-brown wavy camouflage patterns, large forward-facing eyes, and characteristic jerky, alert movements.
Similar Species
Other jumping spiders such as Phidippus species, which tend to be larger, hairier, and more brightly colored, or Habronattus species which favor ground litter.
Life Cycle
Females construct a silken retreat where they lay eggs guarded until hatching. Spiderlings undergo multiple molts over a one-to-two-year lifespan, maturing through distinct developmental stages.
Ecological Importance
Acts as an effective natural pest control agent in gardens and around homes by consuming large numbers of nuisance insects without the need for chemical interventions.
Conservation Status
Secure and widespread, with stable populations throughout its natural range, facing no major conservation threats.
Interesting Facts
Tan jumping spiders can jump up to 50 times their own body length using a sudden hydraulic pressure change in their legs. They can also recognize human faces and respond to laser pointers like domestic cats.
Photography Tips
Use a macro lens with natural side lighting to highlight the texture and eye arrangement. Approach slowly to avoid triggering an escape jump.
Identified: 2026-08-30T20:15:32.904524