Missouri is home to a native tarantula species. These large spiders are a natural part of the state’s wildlife. While their appearance might be imposing, they are generally not considered a threat to humans.
The Missouri Tarantula
The tarantula species found in Missouri is the Oklahoma Brown Tarantula, scientifically known as Aphonopelma hentzi. This species is the only tarantula native to Missouri, also commonly referred to as the Texas Brown Tarantula or the Missouri Tarantula in different regions. Aphonopelma hentzi is a stocky, hairy spider with a dark chocolate brown body and legs, often displaying reddish hairs on its carapace. Adults typically achieve a leg span of 4 to 5 inches, with some individuals reaching up to 6 inches.
Female Aphonopelma hentzi are known for their longevity, often living 20 to over 30 years. Males have a much shorter lifespan, typically surviving only a few years, often just months after reaching sexual maturity. Despite their size, these tarantulas are docile, preferring to avoid confrontation.
Habitat and Behavior
Within Missouri, Aphonopelma hentzi is predominantly found in the southern and western parts of the state, particularly within the Ozarks region. They thrive in dry, rocky glades, prairies, and grasslands. These tarantulas construct silk-lined burrows, often utilizing abandoned tunnels or natural cavities under rocks and logs for shelter. They line the entrances of their burrows with webbing, which serves as an early detection system for passing prey.
As nocturnal predators, Missouri tarantulas are most active at night. Their diet primarily consists of insects like crickets, grasshoppers, and beetles, and other small invertebrates, though they may also prey on small lizards or rodents. Unlike many spiders, Aphonopelma hentzi are ambush hunters and do not spin large webs to capture prey.
Mature males search for mates during late summer and early fall. Females lay their eggs, sometimes up to 1,000, within a silk hammock inside their burrows. Spiderlings remain with the mother for a short period before dispersing to establish their own burrows.
Interactions and Safety
Missouri tarantulas are non-aggressive, primarily fleeing or hiding when disturbed. When threatened, their defensive behaviors include standing on their hind legs and raising their front legs in a warning display. They may also kick small, barbed urticating hairs from their abdomen, which can cause irritation or a mild allergic reaction.
Bites from Aphonopelma hentzi are uncommon, typically occurring only if the tarantula is provoked, handled, or accidentally stepped on. Their venom is mild and not medically significant for humans. A tarantula bite is often compared to a bee sting, resulting in localized pain, swelling, and redness that usually subsides within 24 to 48 hours. While rare, an allergic reaction to the venom or urticating hairs is possible; symptoms like difficulty breathing or facial swelling necessitate immediate medical attention. Always observe these spiders from a distance and avoid provoking them.