Centruroides exilicauda

(Wood, 1863)

Today's subject is Centruroides exilicauda (Wood, 1863). The generic name Centruroides is from the Greek words centr-, meaning "pointed," and ur, meaning "tail." The genus was originally called Centrurus, but had to be changed to Centruroides because the name Centrurus was already in use for another animal. The "-oides " ending means "like" or "the form of," so the name really means "like Centrurus." The specific name exilicauda is from the Latin words meaning "slender" (exili-) and "tail" (cauda).

Centruroides exilicauda

This scorpion is in the family Buthidae and belongs to the Exilicauda species group of the genus Centruroides. Synonyms include Scorpio (Atreus) californicus Girard, 1853, Centruroides sculpturatus Ewing, 1928 and Centruroides gertschi Stahnke, 1940. This scorpion exhibits a variety of different forms and color morphs and almost certainly represents a cryptic species complex.

Original Description

Wood, H.C. 1863. Descriptions of new species of North American Pedipalpi. Proceedings of the Academy of Natural Sciences of Philadelphia 1863:107-112.


Centruroides exilicauda is found in southeastern California, Arizona, Nevada, southern Utah, and soutwestern New Mexico in the United States. It is also found throughout the Baja Peninsula and western Sonora in México. A typical "bark" or "crevice" scorpion, Centruroides exilicauda is commonly encountered in a variety of situations. It is most commonly found under rocks, logs, the bark of trees, and other surface objects.

Fun Facts

In the United States, this species was formerly called Centruroides sculpturatus Stahnke, 1940. This name, however, was synonymized under Centruroides exilicauda by S.C. Williams in 1980. Centruroides sculpturatus gained fame as "the Arizona deady scorpion" through the 50's and 60's. However, this scorpion, like most, is only dangerous or deadly to infants and small children. These medium-sized scorpions cannot inject a sufficient quantity of venom to kill an adult human. Certain human individuals, however, may be allergic to the venom and can experience life threatening side effects when stung (as occurs with bee stings).

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