Tan Jumping Spider, Flatties
Platycryptus undatus
Salticidae (Jumping Spiders), Order Araneae. Key family characteristics include excellent stereoscopic vision with large anterior median eyes, acute hunting capabilities, and the ability to leap great distances without webs.
Physical Description
Compact, robust body with a flattened profile designed for slipping into narrow crevices under bark and wood. The cephalothorax is broad and square-fronted, and the abdomen is oval and slightly elongated, covered in fine hairs.
Size Estimate
Body length typically ranges from 8 to 13 millimeters for females and 7 to 10 millimeters for males, with a leg span proportional to a medium-sized jumping spider. This specimen appears to be a sub-adult or adult.
Coloration & Markings
Mottled patterns of tan, gray, brown, and black providing exceptional camouflage on tree bark and weathered wood. Features distinctive wavy transverse bands across the abdomen and carapace.
Web Type
Does not build a web to catch prey. Instead, they construct small, silken retreat sacs under bark, rocks, or siding for molting, sleeping, and brooding.
Eye Arrangement
Typical salticid pattern consisting of eight eyes arranged in three rows. The anterior median eyes are exceptionally large and provide high-resolution, color vision, while smaller lateral and posterior eyes monitor movement.
Leg Characteristics
Relatively short, robust legs with distinct dark and light banding. Equipped with dense pads of hairs (scopulae) and claws that allow them to climb smooth vertical surfaces with ease.
Venom & Safety Information
Venom Information
Contains neurotoxic venom used primarily to subdue small invertebrate prey. Potency is extremely low and harmless to humans and large pets.
Medical Significance
Not medically significant. Bites are extremely rare, non-toxic, and typically cause no more than a mild, temporary localized irritation similar to a mosquito bite.
Safety Recommendations
No special safety measures needed as they are completely harmless. If relocation is desired, gently guide the spider into a cup using a piece of paper.
Habitat & Behavior
Habitat & Range
Found throughout eastern North America. Prefers vertical wooden structures, fences, tree trunks, and the exterior walls of wooden buildings where its camouflage matches the substrate.
Behavior & Temperament
Active diurnal hunter relying on stalking and powerful leaps to capture prey. Highly inquisitive, often turning to face human observers. Generally docile and reluctant to bite unless severely cornered.
Diet & Prey
Feeds on a wide variety of small insects including flies, mosquitoes, aphids, and other spiders. Hunts by actively stalking and pouncing with calculated precision.
Seasonal Activity
Most active during spring and summer months. Overwinters as immature or mature individuals tucked away inside silken retreat sacs under bark or siding.
Description
The Tan Jumping Spider is a charismatic and harmless visitor to wooden structures and gardens across eastern North America. With its flattened body and exceptional vision, it navigates vertical surfaces with agility, hunting insect pests while observing its surroundings with curious, intelligent-looking eyes.
Key Features
Flattened body profile, mottled tan and gray coloration with wavy bands, large forward-facing eyes, and characteristic salticid jumping behavior.
Similar Species
Other jumping spiders such as Phidippus species, which are generally much larger, hairier, and more brightly colored or contrastingly marked.
Life Cycle
Females construct silk egg sacs in sheltered retreats and guard them until hatching. Spiderlings undergo several molts to reach maturity, with a typical lifespan of around one to two years.
Ecological Importance
Acts as an effective natural pest controller in gardens and around homes by consuming large numbers of nuisance insects.
Conservation Status
Secure and widespread throughout its native geographic range with stable populations.
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 also exhibit complex visual courtship displays.
Photography Tips
Approach slowly to avoid startling them. Use a macro lens from a low angle to capture the face-on perspective highlighting their large, expressive anterior eyes.
Identified: 2026-09-16T19:38:21.956010