Striped bark scorpion, Centruoides vittatus (Say) (Scorpionida: Buthidae).
Photo by G. McIlveen, Jr.
Common Name: Striped bark scorpion
Scientific Name: Centruoides vittatus (Say)
Order: Scorpionida
Description: Scorpions are non-insect arthropods. Adults average about 2-3/8 inches (60 mm) in length, with the tail being longer in the males than in the females. Body color of adults varies from yellowish to tan, marked with two broad, blackish stripes on the upper surface of the abdomen. Populations in the Big Bend area may be only faintly marked or completely pale. There is a dark triangular mark on the front (anterior) portion of the head region (carapace) in the area over the (median and lateral) eyes. Younger specimens may be overall lighter in color, and basis of the pedipalps and the last segment of the body (postabdomen) is dark brown to black. The key recognition characters for this species are the slender pedipalps and the long slender tail.
Life Cycle: Scorpions are capable of reducing their metabolic rates to very low levels. Mating apparently takes place in the fall, spring and early summer. All scorpions are born live (viviparous), and embryos are nourished in the female’s body (in utero or via a “placental” connection). Development (gestation) is estimated to take about 8 months, but varies depending on the species. Young are born in litter sizes from 13 to 47, averaging about 31. The young climb to the mother’s back after birth and soon molt. After the first molt they disperse to lead independent lives. Immature scorpions molt an average of six times before maturity. Some species may live for 20 to 25 years but the typical scorpion probably lives between three and eight years. Adults may produce several broods.
Habitat, Food Source(s), Damage: Scorpions use the pincers to capture and hold prey. This species occurs under rocks, under boards, and in debris. It can be found indoors or outdoors in a wide variety of habitats (pine forests in East Texas, rocky slopes, grasslands, juniper breaks in other parts of the state).
Centruroides are active foragers and do not burrow. They are considered “bark scorpions” with a distinct association with dead vegetation, fallen logs, and human dwellings. It is common for them to climb, and many reports in homes are associated with attics. Scorpions remain sheltered in the daytime and become active at night. This behavior helps with regulating temperature (thermoregulation) and water balance. Their bodies are covered with a waxy cuticle which also helps reduce water loss. For reasons yet unknown, the scorpion cuticle fluoresces under ultraviolet light i.e., a blacklight.
Pest Status: Most common and widespread scorpion in Texas; stings are painful and produce local swelling and itching that may persist for several days. Reaction to the bite may vary based on sensitivity of the individual. Non-lethal stings may be mild to strong and produce edema (swelling), discoloration, numbness, and pain which may last for several minutes to several days. Deaths attributed to this species are not well substantiated. There are no scorpions in Texas that are considered lethal to man.
For additional information, contact your local Texas A&M AgriLife Extension Service agent or search for other state Extension offices.
Literature: Polis 1990; Shelley & Sissom 1995.