Fourteen specimens of Vaejovis coahuilae Williams 1968 were born in the laboratory and reared in an incubator at a near-constant 27 °C. A single female reached maturity at the 8^th instar, as previously hypothesized, but unverified, in this species. Two other specimens reached the 7^th instar, but the male died at the molt and the female was not yet mature. Data on the duration and morphometrics of observed instars are provided for all specimens.