Giant Redheaded Centipede — Fact Sheet

Scientific name: Scolopendra heros Girard, 1853 (specifically the castaneiceps color variant in Texas) Common names: Giant redheaded centipede, Texas redheaded centipede, giant desert centipede, giant Sonoran centipede, Texas black-tailed centipede, Arizona desert centipede Class: Chilopoda (Order Scolopendromorpha, Family Scolopendridae) Status in the San Antonio / Boerne corridor: Native, present, locally common in Hill Country — the largest centipede in North America

At a glance

Size	6.5–8 inches (170–200 mm) typical; up to 9+ inches in captivity
Color	Red or rust-orange head, dark green-black body, yellow legs, yellow-tipped black caudal legs
Body type	Long, segmented, 21 or 23 body segments, one pair of legs per segment (42 or 46 legs total)
Lifespan	Slow-growing; over a decade in some individuals
Sting mechanism	"Bite" is actually venom injection through forcipules (modified front legs); walking legs may also pierce skin
Active period	Year-round in Hill Country; nocturnal; emerges in cloudy/wet weather
Habitat	Under rocks, logs, leaf litter; occasionally enters homes during weather extremes

Why this fact sheet exists

Giant redheaded centipedes are arthropods, not insects (or arachnids). They belong to a separate class — Chilopoda — that diverged from insects and arachnids hundreds of millions of years ago. They are absolutely included in this fact sheet series because:

• Customer queries about "stinging things in Texas" inevitably include centipedes
• The visual is unforgettable — an 8-inch red-headed black-and-yellow segmented monster moving across a tile floor in the middle of the night is the stuff of homeowner nightmares
• The bite/sting is genuinely painful and warrants medical understanding
• The species is iconic Texas wildlife — Texas Parks and Wildlife Magazine has covered it as "the stuff of nightmares," and identification confidence helps homeowners distinguish it from less significant centipede species
• They genuinely enter homes during weather extremes, producing recurring service inquiries

So this is a stinging-pest fact sheet about an arthropod that isn't even closely related to anything else in this series. It earns coverage by being unmistakable, common to Hill Country, and the source of legitimate fear (deserved or otherwise).

Identification

The giant redheaded centipede is unmistakable. There is essentially nothing else like it in North America.

Diagnostic features:

• Length: 6.5 to 8 inches in the wild, occasionally larger; this is dramatically longer than any other US centipede
• Bright red or rust-orange head that contrasts sharply with the dark body — this is the namesake feature
• Dark green-black body segments
• Bright yellow walking legs — sometimes described as "yellow-orange"
• Black caudal legs (rear) with yellow tips — these look like antennae extending backward
• 21 or 23 body segments with one pair of legs per segment (so 42 or 46 legs total — far short of "100" implied by the name "centipede")
• Long, undulating movement — the segmented body flexes from side to side as it moves
• Two genuine antennae on the head, plus the rear "antenna-like" caudal legs that confuse predators

The aposematic (warning) coloration of black, yellow, and red serves as a visual signal to predators that this animal is venomous.

What's the "stinger" on the back?

Common confusion: the appendages on the rear are not stingers. They are caudal legs (sometimes called rear pseudoantennae) — modified walking legs that have evolved to look like the front antennae. They are prehensile and can pinch, but they don't deliver venom.

The actual venom delivery system is at the front of the head — the forcipules (also called maxillipeds), which are modified front legs that have evolved into venom-delivery structures connected to glands. When the centipede "bites," it is actually stabbing with these modified legs and injecting venom from glands at their bases.

The deception is clever evolutionarily. Predators that attack the rear (mistaking the caudal legs for the head) are essentially attacking the safer end. The actual head — with the deadly forcipules — gets to attack from the other direction.

Distinguishing from other centipedes

Texas hosts several centipede species, but only one looks like this:

• **House centipede (Scutigera coleoptrata):** Up to 1.5 inches long, gray with long delicate legs visible from above. Common indoor species. Bite is mild.
• Soil centipedes (Geophilomorpha): Long, very thin, pale; up to a few inches. Found in soil and leaf litter. Bite typically too small to penetrate human skin.
• Stone centipedes (Lithobiomorpha): Up to 1 inch, brown, fast-moving. Found under rocks and bark.
• **Giant redheaded centipede (Scolopendra heros): 6-8+ inches**, distinctive coloration as above.

If you have an 8-inch centipede in your house, you have Scolopendra heros. Period.

Biology and behavior

Predator on basically everything smaller

Giant redheaded centipedes are aggressive nocturnal predators with an extraordinarily broad diet:

• Insects and other arthropods — primary diet
• Spiders, including tarantulas in some cases
• Small rodents — mice, baby rats
• Reptiles — small lizards, juvenile snakes
• Amphibians — toads
• Flying insects — they can reach into the air to grab passing flies, moths, and beetles

Their tropical relatives (Scolopendra gigantea of South America) have been documented preying on bats caught in flight. S. heros is smaller but follows the same general predatory strategy. They are essentially apex predators of the ground-level invertebrate world.

The hunting sequence: 1. Centipede locates prey through vibration sensing and chemical cues 2. Walking legs grasp the prey 3. Front of body curves around, bringing forcipules to prey 4. Forcipules pierce prey and inject venom 5. Venom paralyzes prey (within seconds for small prey, longer for larger) 6. Centipede consumes prey using strong mandibles

The forcipules are modified front legs. The walking legs themselves may also have a venom-delivery capacity that contributes to the painful "tracking" effect when a centipede walks across human skin — small punctures and blisters can result from each step.

The venom

The venom of Scolopendra heros is similar in composition to other Scolopendra species venoms, but has not been thoroughly characterized due to the difficulty of extracting it in significant quantities (small venom glands) and rapid deterioration when processed.

Known components:

• Serotonin — pain-inducing neurotransmitter
• Histamine — pain and inflammation
• Lipids and proteins — including cardiotoxic proteins
• Hemolytic phospholipase A — disrupts cell membranes (cytolytic)
• Insect-specific neurotoxins — paralyze insect nervous systems
• Vertebrate-targeted toxins — interfere with autonomic nervous system function in small vertebrates

The venom acts primarily as a cytolysin — compromising cell membranes and rupturing cells. This explains both the pain (cell membrane disruption activates pain receptors) and the localized tissue damage that can sometimes follow severe envenomations.

Lifespan and reproduction

Scolopendra heros is slow-growing and long-lived for an arthropod. Individuals can live over a decade in suitable conditions. This is dramatically longer than most insect species and contributes to their establishment in stable habitats.

Reproduction:

• Females lay 12-60 eggs in summer, in soil chambers or under rocks
• Females coil around their egg masses for protection
• Mothers groom the eggs continually to remove fungal contamination
• Eggs hatch after about two months of maternal incubation
• Mothers continue to protect newly-hatched young through their first vulnerable instars
• Maternal care in centipedes is one of the more striking parental behaviors among arthropods
• Number of body segments is fixed throughout life — they grow by molting and adding body length within existing segments
• Lost legs can regrow over subsequent molts

Why they enter homes

Hill Country homeowners regularly find giant redheaded centipedes inside houses, particularly during weather extremes:

• Hot, dry summer weather: Centipedes seek cool, humid microclimates. Bathrooms, basements, kitchens with water sources are attractive.
• Heavy rain and flooding: Soil saturation forces centipedes to higher ground, including up walls and into structures.
• Cold winter snaps: Centipedes seek warm refuges. Homes provide stable heated environments.
• Drought followed by sudden rain: Triggers movement as prey availability shifts.

Centipedes typically enter through:

• Gaps under doors (especially garage and exterior doors)
• Foundation cracks
• Plumbing penetrations
• Weep holes
• Through stacked landscape stone and rock features adjacent to foundation

Once inside, they hunt for prey (insects, spiders) and seek hiding places. They can survive for weeks indoors if water and prey are available, but typically die or leave when food becomes scarce.

Local context — San Antonio and the Hill Country

Giant redheaded centipedes are present across the entire Hill Country region but are most commonly encountered in:

• Hill Country acreage (Boerne, Bulverde, Spring Branch, Comfort, Bandera, Bergheim, Helotes): Native scrub habitat with abundant rock crevices, leaf litter, and prey populations supports established centipede populations. Most calls come from these areas.
• Custom homes with extensive rock landscape features: Stacked stone walls, dry creek bed installations, native plant beds with rock mulch — all provide ideal habitat. Centipede sightings on these properties are recurring annual events.
• Wooded subdivisions (Stone Oak / Sonterra / Encino Park): Native canopy with leaf litter beds along property edges.
• Hill Country state parks and natural areas: Pedernales Falls, Government Canyon, Hill Country State Natural Area — visible during summer hikes, often under rocks moved by hikers.
• Cave systems and karst features: Giant centipedes are documented in many Texas cave systems, where they prey on cave invertebrates and occasional vertebrate visitors.

Interior San Antonio: Less common. Urban hardscape doesn't provide ideal habitat. Occasional sightings near city parks with mature canopy and natural areas, but uncommon in dense neighborhood lots.

The signature local presentation: a homeowner in Boerne or Fair Oaks Ranch wakes in the night to find an 8-inch centipede on the bathroom floor or hallway. They are alarmed and want it removed immediately. Identification, removal, and discussion of exclusion options follow.

When they are most often encountered

• June through October: Peak Hill Country activity. Warmest months, highest prey availability.
• After heavy rain: Soil saturation drives movement.
• Late summer drought: Centipedes seek moisture, increasing structural intrusion.
• Pre-dawn or evening: Active foraging time.

Pet interactions

Dogs and cats encountering giant redheaded centipedes can be bitten if they investigate too closely. Reactions vary:

• Small dogs: localized swelling, discomfort, occasional systemic reactions
• Large dogs: typically minor reactions
• Cats: variable, depending on bite location
• Veterinary attention warranted if systemic symptoms develop or if bite is on face/throat

Risk to humans and pets

Moderate. The bite is genuinely painful, but rarely medically serious for healthy adults.

Typical bite effects:

• Sharp, searing local pain (often described as similar to a wasp sting or worse)
• Pain peaks within minutes, gradually subsides over hours
• Local swelling and erythema (redness)
• Two visible puncture wounds at bite site
• Pain may persist for several hours, sometimes longer
• Localized skin necrosis in some cases
• May feel like a "bee sting" but typically more intense and more prolonged

Less common effects:

• Headache, dizziness, nausea
• Lymphangitis (red streaking along the lymphatic vessels) — documented in case reports of S. heros bites in Texas
• Localized lymphadenopathy
• Eosinophilic cellulitis
• Hemorrhagic blisters at bite site

Rare but serious effects (documented in case reports):

• Rhabdomyolysis (muscle tissue breakdown) leading to kidney failure
• Myocardial infarction (heart attack) — documented in at least one case from Scolopendra envenomation
• Anaphylaxis in allergic individuals
• Severe systemic responses requiring hospitalization

No confirmed deaths from Scolopendra heros envenomation in the medical literature. The Texas Parks and Wildlife Magazine summary: "consider centipede bites to be similar to bee stings: usually mild, but occasionally resulting in acute reactions."

The pediatric and elderly populations are at higher relative risk for severe reactions. Allergic individuals should treat centipede bites with the same seriousness as wasp stings.

First aid

• Wash the bite area with soap and water immediately
• Apply ice or cold compress wrapped in cloth (10 minutes on, 10 minutes off)
• Take oral acetaminophen or ibuprofen for pain
• Watch for signs of infection over following days
• Seek medical attention if:

- Severe systemic symptoms develop (chest pain, breathing difficulty, severe nausea) - Signs of allergic reaction - Lymphangitis (red streaking from bite) - Bite is on face, neck, or other sensitive area - Symptoms persist or worsen beyond 24 hours

Treatment approach

Centipede control is genuinely challenging and not a routine pest service. Reasons:

• Centipedes don't form colonies — each individual is independent
• They are highly mobile and travel significant distances
• They are nocturnal — observation and treatment timing are difficult
• They live primarily outdoors and only enter structures opportunistically
• No species-specific bait or attractant exists for treatment delivery
• Insecticide treatments that affect centipedes also affect their prey species (which is generally counter to broader pest management goals)

Our approach for properties with recurring giant redheaded centipede issues:

Identification and threat assessment:

• Confirm species (distinguishes S. heros from less significant species)
• Assess frequency of indoor encounters
• Identify likely entry points and habitat sources

Habitat modification — primary intervention:

• Remove or relocate stacked stone landscape features within 10-20 feet of structure
• Clear leaf litter, woodpiles, debris within 20 feet of foundation
• Trim vegetation away from contact with structure
• Address moisture issues that attract prey insects
• Dethatch and rake landscape beds during off-season

Exclusion:

• Door sweeps on exterior doors (especially garage door)
• Seal foundation cracks and weep holes (with caution — weep holes serve a moisture-management function)
• Repair window screens
• Caulk plumbing penetrations
• Address gaps under siding

Chemical treatment:

• Perimeter treatment with residual insecticide (microencapsulated formulations or wettable powders) on foundation walls and immediate landscape edges
• Granular treatment in landscape beds adjacent to structure
• Dust treatment in identified entry-point voids (wall voids, plumbing penetrations)
• Treatment of garage interior on quarterly schedule for chronic problems

Indoor capture:

• Glue traps placed along walls and in corners can capture transient centipedes
• Cover removable for safe disposal of captured specimens
• Useful for monitoring activity over time

Realistic expectations:

• Total elimination is not possible on properties with adjacent native habitat
• Goal is significant reduction of indoor encounters
• Properties with active control programs can typically reduce indoor sightings to 1-2 per year or fewer
• Annual or semi-annual treatment is recommended for properties with recurring issues

Odd, funny, and genuinely true

• The bite isn't a bite. Centipedes don't have stingers and their "bite" isn't from their mandibles — it's a venom injection from modified front legs called forcipules. Each forcipule is a single leg that has evolved into a venom delivery structure connected to a venom gland. The animal is essentially stabbing with modified legs. This is a distinctive feature of all centipedes.
• ***Scolopendra heros* doesn't actually have 100 legs.** Despite the family name "centipede" (Latin for "hundred-footed"), this species has either 21 or 23 body segments with one pair of legs per segment — a maximum of 46 legs. No centipede species actually has exactly 100 legs; counts range from 30 to over 300 across the class.
• The yellow-tipped black "antennae" on the back are not antennae. They are caudal legs — modified rear walking legs that have evolved to look like the front antennae. The visual deception confuses predators about which end is the head, drawing attacks toward the safer rear end. The actual head with the venomous forcipules is at the other end.
• Females are dedicated mothers. Female Scolopendra heros coil around their egg masses for the entire two-month incubation period, grooming the eggs continually to prevent fungal infection. Mothers continue to protect newly-hatched young through their first vulnerable instars. This is one of the more striking examples of maternal care in arthropods.
• They can live over a decade. Most arthropods live months to a few years; S. heros individuals can live 10+ years in suitable conditions. This longevity is part of why they establish stable populations in good habitat.
• Lost legs grow back. Through subsequent molts, S. heros can regenerate appendages lost to predation or injury. Centipedes commonly regenerate legs across multiple molts.
• They can grab prey out of the air. S. heros is documented catching small flying insects mid-flight by reaching upward with the forward portion of its body — a remarkable hunting capability for a primarily ground-dwelling predator.
• Their tropical cousins eat bats. Scolopendra gigantea of South America has been documented hanging from cave ceilings to catch flying bats. The North American giant redheaded centipede is smaller but follows the same predatory adaptability.
• They can prey on small rodents and snakes. Despite being invertebrates, large S. heros individuals successfully prey on small mice, juvenile rats, small lizards, juvenile snakes, and toads. This is essentially unprecedented size-scale predation by an arthropod against vertebrates.
• The forcipules can deliver venom into prey larger than themselves. The maxillipeds are mechanically capable of penetrating the skin of small mammals and reptiles, and the venom is potent enough to immobilize prey items disproportionate to the predator's size.
• A 79-year-old Texan was hospitalized in 2017 with lymphangitis after a Scolopendra heros bite that woke him from sleep. The case was published in Annals of Emergency Medicine and documented localized lymphangitis tracking up his arm from the bite site on his hand. He recovered, but the case report exists specifically to remind clinicians that centipede bites can cause serious local and systemic reactions.
• Folk legend that centipede bites kill people is unsupported. Texas Parks and Wildlife Magazine notes: "this story appears to be no more than a tall tale, and giant redheaded centipede bites have never resulted in a confirmed death." Rare cases of serious complications have been documented (including kidney failure and heart attack from severe envenomation), but no confirmed fatality.
• The walking legs may also be venomous. When a centipede walks across human skin, small wounds and blisters can sometimes form along the path of the walking legs, suggesting that some venom delivery occurs through the legs themselves, not just the forcipules. This is documented behavior but not as well-characterized as the forcipule bite.
• They are slow-growing apex predators of the invertebrate world. Unlike most insects, which complete their life cycles in months, S. heros takes years to reach mature size. The slow life history and high predatory output makes them ecological keystone species in their habitats.
• Centipedes belong to a class of arthropods (Chilopoda) that diverged from insects about 420 million years ago. Scolopendra heros is more distantly related to a honey bee than humans are to fish. The body plan is one of the older successful arthropod designs, dating back to the Silurian period.
• The Texas Parks and Wildlife Magazine description of the centipede as "the stuff of nightmares" was meant affectionately. The magazine's coverage emphasizes that centipedes are valuable predators and that the appropriate human response is "respectful coexistence" rather than panic — though they acknowledge that finding an 8-inch redheaded centipede in your bathroom at 3 AM understandably tests that philosophy.

FAQ hooks (for LuperIQ / SEO)

• What is the giant centipede in Texas?
• How dangerous is a Texas redheaded centipede bite?
• Are giant centipedes in Texas poisonous?
• How do I keep centipedes out of my house?
• Centipede in my house — what do I do?
• Can a centipede kill a person?
• How big do Texas centipedes get?
• What's the difference between a centipede and a millipede?

Sources consulted for this fact sheet include the Wikipedia account of Scolopendra heros, Texas Parks and Wildlife Magazine's "Giant Redheaded Centipedes Are the Stuff of Nightmares" feature, the 101 Highland Lakes natural history coverage, the American Association of Poison Control Centers' centipede sting guidance, the 2017 Annals of Emergency Medicine case report "Lymphangitis From Scolopendra heros Envenomation: The Texas Redheaded Centipede" (Essler et al.), centipede venom characterization research from ScienceDirect, and the A-Z Animals comprehensive species profile. Maternal care behavior reflects general scolopendrid biology documented in Lewis 1981. Predation behavior documentation is from multiple species accounts including Shelley 2002 and Mercurio 2011.