Tan Jumping Spider, Flattied Jumping Spider
Platycryptus undatus
Salticidae (Jumping Spiders), Order Araneae. Key family characteristics include exceptional daytime vision with four pairs of eyes arranged in three rows, and specialized legs adapted for jumping rather than spinning traditional webs.
Physical Description
The spider has a compact, robust body with a flattened cephalothorax and an elongated, oval-shaped abdomen. The body is covered in fine, dense setae giving it a velvety texture. Distinctive enlarged anterior median eyes give it a curious, intelligent facial expression.
Size Estimate
Body length typically ranges from 8 to 13 millimeters for females, with males slightly smaller. Leg span is roughly 15 to 25 millimeters. The specimen appears to be an adult or sub-adult.
Coloration & Markings
Mottled patterns of brown, tan, grey, and black arranged in wavy bands across the body, providing excellent camouflage against tree bark and wooden surfaces. Males often feature white facial fringes and distinctive banded front legs.
Web Type
No web is built for catching prey. Instead, they construct small, silken retreat sacs under loose bark, in crevices, or on building sidings where they rest at night and during molting or egg-laying.
Eye Arrangement
Eight eyes arranged in three distinct rows. The anterior median eyes are exceptionally large and provide high-resolution, color vision. Two smaller pairs on the sides and top complete the field of view.
Leg Characteristics
The front legs are often slightly thickened and held out to the sides or raised, especially in males showcasing courtship or defensive posture. Legs are moderately short, muscular, and equipped with scopulae for traction.
Venom & Safety Information
Venom Information
Contains neurotoxic venom tailored for subduing small invertebrate prey. It has low potency relative to humans and is generally incapable of causing systemic effects.
Medical Significance
Harmless to humans. Bites are extremely rare, usually only occurring if the spider is directly squeezed. Symptoms, if any, are limited to mild localized pain and minor redness.
Safety Recommendations
No special safety measures required. If found indoors, they can be gently relocated outside using a cup and a piece of paper. They pose no threat to humans or pets.
Habitat & Behavior
Habitat & Range
Found widely across eastern North America. Prefers arboreal habitats, woodland edges, tree trunks, wooden fences, and the exterior walls of wooden buildings where its camouflage is highly effective.
Behavior & Temperament
Active diurnal hunter relying on stalking and powerful leaps to capture prey. Very curious and attentive to human movement. Generally docile, rarely biting unless trapped tightly against skin.
Diet & Prey
Carnivorous, feeding on a wide variety of small insects such as flies, gnats, ants, and small moths. Discovers prey visually, stalks within range, and leaps to secure it.
Seasonal Activity
Most active during the warm spring and summer months. Overwinters by finding shelter in protected silk cocoons under bark or in crevices.
Description
The Tan Jumping Spider is a charismatic arachnid frequently encountered on wooden structures and tree trunks. With its remarkable forward-facing eyes and acrobatic leaping ability, it serves as a fascinating and harmless companion around homes and gardens.
Key Features
Flattened body profile, large forward-facing eyes, mottled brown and tan camouflage coloration, and jerky, alert movements combined with impressive jumping ability.
Similar Species
Other jumping spiders such as Phidippus species (bold jumper), which are typically larger, fuzzier, and possess more contrasting black and white or metallic coloration.
Life Cycle
Females construct silken egg sacs in hidden retreats, guarding them until spiderlings emerge. They undergo multiple molts over a one to two-year lifespan, mating typically in the spring.
Ecological Importance
Acts as an effective natural pest controller by preying on common household and garden insect pests, helping maintain balanced micro-ecosystems.
Conservation Status
Not threatened or endangered; stable populations widespread throughout its natural range.
Interesting Facts
Tan jumping spiders can leap distances up to several times their own body length using a sudden hydraulic pressure change in their legs. They do not use draglines for everything, but they do anchor a safety line before making major leaps.
Photography Tips
Use a macro lens in bright natural daylight or with a diffused flash. Approach slowly to avoid startling them, and focus on the face to capture their prominent, expressive eyes.
Identified: 2026-09-16T02:45:55.439215