Jumping Spider Health Signs: How to Tell If Your Spider Is Sick

Researched and written by the ExoPetGuides editorial team with AI-assisted drafting. All veterinary references and husbandry parameters independently verified.

Signs of a Healthy Jumping Spider

Before learning what sick looks like, you need a baseline for what healthy looks like. A healthy captive jumping spider displays consistent behavioral and physical markers that you can monitor with simple daily observation.

Physical indicators of good health:

• Plump, rounded abdomen. The abdomen (opisthosoma) should appear full without being distended. In well-fed species like Phidippus regius, the abdomen has a smooth, slightly glossy surface with no wrinkling or creasing.
• Clear, responsive eyes. The primary anterior median eyes (AME) should be dark and reflective. The spider should actively track movement with its primary eyes, tilting its cephalothorax to follow objects of interest.
• Full, intact legs. All eight legs should be present and functional. Jumping spiders can regenerate lost legs during subsequent molts, but missing legs indicate past injury or stuck-molt complications.
• Clean, well-maintained silk retreat. A healthy spider builds, uses, and reinforces its silk retreat regularly. The retreat should appear well-structured, not tattered or abandoned.
• Normal coloration. Colors should match the species standard. Phidippus regius females are gray-brown with white markings; males have black bodies with iridescent chelicerae. Fading, darkening, or unusual patches warrant closer attention.

Behavioral indicators of good health:

• Active enclosure patrol during daytime hours.
• Prompt hunting response when prey is introduced. A healthy spider detects, stalks, and pounces on appropriately-sized prey within minutes.
• Regular drinking from misted water droplets.
• Head-tilting and visual tracking of movement near the enclosure.
• Consistent silk production (draglines during movement, retreat maintenance).

For a baseline care reference, see the jumping spider care guide.

Common Health Problems in Jumping Spiders

Most jumping spider health problems in captivity are environmental in origin. Dehydration, incorrect humidity, and enclosure hygiene issues account for the majority of illness cases. Genetic disease and parasites are less common in captive-bred specimens from reputable breeders.

Dehydration

The most common health problem in captive jumping spiders. Dehydration develops rapidly because jumping spiders have a high surface-area-to-volume ratio and lose moisture quickly in dry environments.

Signs:

• Shrunken, wrinkled abdomen (the most reliable visual indicator)
• Lethargy and reduced movement
• Reluctance or inability to hunt
• Legs curling inward (advanced dehydration; indicates critically low hemolymph volume)
• Inability to jump

Causes: Insufficient misting, low ambient humidity, excessive ventilation, enclosure placed near a heat source or air conditioning vent.

Action: Increase misting frequency to daily. Place small water droplets directly in front of the spider. If the spider is unresponsive, place a damp cotton ball touching the spider’s front legs for passive moisture absorption. See the jumping spider hydration guide for the full emergency protocol.

Dysecdysis (Stuck or Failed Molt)

Molting failure is the second most common cause of death in captive jumping spiders. It occurs when the old exoskeleton does not separate cleanly from the new one, trapping the spider partially inside the old cuticle.

Signs:

• Spider appears stuck halfway out of its old exoskeleton
• Deformed or misshapen body after molt attempt
• Spider is motionless and partially encased in shed skin for more than 24 hours
• Missing or malformed legs after molt

Causes: Insufficient humidity during the molt, physical disturbance during the molting process, nutritional deficiency weakening the new cuticle.

Action: If the spider is actively stuck in a molt, do not pull the old skin off manually. Gently increase humidity in the enclosure to 70-75% by misting more heavily and partially covering ventilation openings. The added moisture may soften the old cuticle enough for the spider to complete the process. If the spider has not freed itself within 12 hours, the situation is critical. Consult an exotic vet experienced with invertebrates. For the full molting guide, see jumping spider molting.

Mites

External mites appear as tiny moving dots (usually white, tan, or reddish) on the spider’s body, legs, or inside the enclosure. Mite infestations stress the spider, reduce its condition, and can transmit secondary infections.

Signs:

• Visible tiny dots moving on the spider’s body or inside the enclosure
• Spider repeatedly rubbing its legs against surfaces (grooming response to irritation)
• Reduced appetite and activity
• Deteriorating body condition despite adequate feeding

Causes: Contaminated substrate, wild-caught feeders, feeder insect cultures harboring grain mites, cross-contamination from other enclosures.

Action: Isolate the affected spider in a clean, temporary enclosure with fresh substrate. Discard all substrate and decor from the infested enclosure and sterilize the enclosure with hot water (no chemical cleaners). Replace substrate and decorations with new, clean materials. Review feeder insect sourcing and storage to eliminate the mite source. For a detailed mite treatment protocol, see the jumping spider mites and parasites guide.

Bacterial and Fungal Infections

Infections in jumping spiders typically present as discoloration, lesions, or unusual growths on the exoskeleton or abdomen.

Signs:

• Dark spots, patches, or lesions on the body that are not normal species markings
• White, fuzzy growths (fungal) on the body, legs, or around the book lungs
• Abdomen discoloration (unusual darkening, reddening, or mottling not associated with pre-molt)
• Fluid leaking from the abdomen or leg joints (hemolymph seepage indicates compromised exoskeleton integrity)
• Foul odor from the enclosure (uncommon but indicates severe bacterial growth)

Causes: Excessive sustained humidity, poor ventilation, contaminated substrate, injury that breached the exoskeleton allowing pathogen entry (source: Journal of Invertebrate Pathology).

Action: Isolate the spider immediately. Reduce humidity to the lower end of the species range (50% for Phidippus). Ensure ventilation is adequate. Clean the enclosure thoroughly. If lesions are spreading or the spider’s condition is deteriorating, consult an exotic vet. There are very limited treatment options for arachnid infections, and early intervention gives the best prognosis.

Nematode Parasites

Internal nematode (roundworm) parasites are occasionally seen in wild-caught jumping spiders or those fed wild-collected insects.

Signs:

• Distended abdomen with no corresponding increase in feeding
• Visible worm-like organisms protruding from the abdomen or spinnerets
• Rapid weight loss despite eating
• Lethargy and progressive weakness

Causes: Ingestion of prey harboring nematode larvae. Most commonly associated with wild-caught spiders or wild-collected feeder insects.

Action: Internal parasites in jumping spiders are generally not treatable given the spider’s small size and the lack of approved arachnid anthelmintics. Prevention through captive-bred sourcing and commercially cultured feeders is the primary defense. If you observe nematodes, isolate the spider and consult a vet, but be prepared for a poor prognosis.

Behavioral Health Red Flags

Sometimes the first sign of illness is a behavior change rather than a visible physical symptom. Pay attention to deviations from your spider’s normal routine.

Environmental Checks When Your Spider Seems Unwell

Before assuming your spider is sick, verify that the enclosure environment meets baseline requirements. The majority of health problems resolve when environmental parameters are corrected.

Temperature: 24-29C (75-85F). Below 18C, metabolism drops dangerously and the spider becomes lethargic. Above 32C, heat stress can be fatal. Use a digital thermometer inside the enclosure, not an ambient room reading.

Humidity: 50-60% for most species (60-70% for Hyllus diardi). Check with a small digital hygrometer. If humidity is consistently below 40%, increase misting frequency and consider reducing ventilation slightly. If above 70% sustained, increase ventilation to prevent mold and respiratory stress. See the temperature and humidity guide for detailed parameters.

Ventilation: Cross-ventilation (openings on two sides of the enclosure) prevents stagnant, humid air. Poor ventilation leads to mold, bacterial growth, and respiratory stress.

Substrate condition: Check for mold (white fuzz on substrate surface), mites (tiny moving dots), or excessive moisture (pooling water, saturated substrate). Replace substrate if contaminated. See the enclosure cleaning guide for maintenance protocols.

Lighting: Jumping spiders need a regular photoperiod (approximately 12 hours light, 12 hours dark) to maintain normal activity cycles. A spider kept in perpetual darkness or under 24-hour lighting will display abnormal behavior that can mimic illness. See the jumping spider lighting guide.

Recent changes: Has anything changed in the past week? New substrate, new decorations, enclosure relocation, new feeder type, room renovation (paint fumes, cleaning chemical fumes), nearby pesticide use? Environmental changes are the most common trigger for sudden health deterioration in spiders.

When to Consult a Veterinarian

Exotic veterinary care for jumping spiders is limited but growing. Not all exotic vets have invertebrate experience, so seek a vet who specifically treats arachnids or has invertebrate medicine credentials.

Consult a vet when:

• The spider has not eaten for more than 14 days and is not in pre-molt.
• Visible lesions, fungal growths, or fluid leakage are present on the body.
• The spider is stuck in a molt for more than 12 hours.
• Nematodes or other parasites are visible.
• Uncoordinated movement, seizure-like behavior, or partial paralysis is observed.
• You have corrected all environmental parameters and the spider’s condition continues to decline.

Finding an invertebrate vet: The Association of Reptile and Amphibian Veterinarians (ARAV) maintains a directory of exotic veterinarians, some of whom treat invertebrates (source: ARAV). Arachnoboards.com also maintains community-sourced vet recommendations by region.

Be realistic about prognosis: Jumping spiders have short lifespans (1-3 years for most species), and veterinary interventions are inherently limited by the spider’s small size. Some conditions (advanced internal parasites, severe dysecdysis, systemic infections) have poor prognoses regardless of treatment. Prevention through proper husbandry is always more effective than treatment.

Health Monitoring Checklist

Use this weekly checklist to catch problems early:

• [ ] Abdomen appears plump and rounded (not shrunken or wrinkled)
• [ ] Spider is active during daytime and patrols the enclosure
• [ ] Spider eats when prey is offered (or is in confirmed pre-molt)
• [ ] No visible mites on the spider or enclosure surfaces
• [ ] No unusual spots, lesions, or growths on the body
• [ ] Legs are intact and functional; no dragging or curling
• [ ] Silk retreat is maintained and in good condition
• [ ] Enclosure temperature is 24-29C
• [ ] Enclosure humidity is 50-60% (or species-appropriate range)
• [ ] No mold visible on substrate or decorations
• [ ] Spider responds to visual stimuli (tracks movement)

If more than two items on this checklist fail in the same week, take action. Check and correct environmental parameters first, then reassess after 3-5 days. If the spider does not improve, consult a vet.

Jumping Spider Lifespan and Age-Related Decline

Understanding natural aging helps distinguish between illness and the normal end-of-life process. Most pet jumping spider species live 1-3 years, with females typically outliving males by 6-12 months (source: PetMD).

Signs of age-related decline (not illness):

• Gradual reduction in hunting drive and prey interest
• Slower, less precise jumping
• Reduced exploration and longer rest periods in the retreat
• Thinning of the legs and mild abdomen reduction
• Faded or dull coloration compared to younger adults

These changes are progressive and gradual over weeks to months. They are not sudden. If a previously healthy spider shows a rapid onset of multiple symptoms, illness or environmental stress is more likely than aging. For species-specific lifespan information, see the jumping spider lifespan guide.

Frequently Asked Questions

How do I know if my jumping spider is dying?

A dying jumping spider typically shows multiple simultaneous symptoms: legs curled under the body, no response to stimuli, refusal to eat or drink for extended periods, and an immobile posture outside the silk retreat. In some cases, the spider may flip onto its back. If the spider is still alive but in this state, attempt emergency hydration (mist droplets near the mouth) and consult a vet, but be prepared for the possibility that intervention may not be effective.

Why is my jumping spider not eating?

The most common reasons for food refusal are pre-molt (the spider is preparing to shed and will not eat for 5-14 days beforehand), dehydration, and incorrect temperature. Check the abdomen first: a darkened, swollen abdomen suggests pre-molt; a shrunken, wrinkled abdomen suggests dehydration. If neither applies, verify enclosure temperature is 24-29C and humidity is 50-60%. If parameters are correct and refusal continues past 14 days, consult a vet. For more details, see jumping spider not eating.

What does a dehydrated jumping spider look like?

A dehydrated spider has a visibly shrunken, wrinkled, or deflated abdomen. The surface of the abdomen may appear creased or puckered rather than smooth and rounded. In advanced dehydration, the legs begin curling inward because low hemolymph volume cannot maintain hydraulic leg extension.

Can jumping spiders recover from illness?

Recovery depends on the condition and how early it is caught. Dehydration is fully reversible with prompt misting and environmental correction. Mild mite infestations can be resolved by enclosure sterilization and feeder source correction. Stuck molts sometimes resolve with humidity support. Bacterial and fungal infections have variable outcomes. Internal parasites generally have poor prognoses. Prevention through proper husbandry is significantly more effective than treatment for all conditions.

How often should I check my jumping spider’s health?

A brief visual check every day (abdomen condition, activity level, retreat status) is sufficient for routine monitoring. A more thorough assessment using the health monitoring checklist once per week catches most problems early enough for intervention.

Is my jumping spider sick or molting?

Pre-molt and illness share overlapping signs (reduced activity, food refusal, hiding). The key differentiator is the abdomen. A pre-molt spider has a darkened, swollen abdomen as new exoskeleton forms underneath the old one. The spider will also seal or reinforce its silk retreat. A sick spider typically has a normal or shrunken abdomen and may avoid its retreat rather than fortifying it. For the full molting guide, see jumping spider molting.

Sources

• Journal of Invertebrate Pathology https://www.sciencedirect.com/journal/journal-of-invertebrate-pathology – arachnid pathology and infection documentation
• Association of Reptile and Amphibian Veterinarians https://arav.org/ – exotic vet directory and invertebrate care standards
• PetMD https://www.petmd.com/exotic/care/jumping-spider – jumping spider health and lifespan reference
• Arachnoboards.com community – health troubleshooting and veterinary recommendations
• University of Florida Entomology Department – Salticidae biology and captive husbandry standards

Editorial Disclosure

This article was researched and written by the ExoPetGuides editorial team with AI-assisted drafting. All health information was verified against veterinary literature and species authorities. ExoPetGuides does not provide veterinary diagnosis or treatment advice.

This guide provides general health information based on current species-authority consensus. It is not a substitute for professional veterinary advice. If your jumping spider shows signs of illness, consult a qualified exotic veterinarian experienced with invertebrates. Do not attempt medication or surgical intervention at home.