New Mexico holds only the thinnest edge of Lacey’s white-ankled mouse’s range: all 84 documented occurrences in the state come from GBIF records rather than photographs. That scarcity fits the larger story. This mouse was only recently split out from a wider white-ankled mouse complex, so its national conservation status still reads not evaluated. New Mexico’s population carries its own NatureServe rank of S3, vulnerable, a real signal at the northern tip of a range centered on Texas’s Edwards Plateau and Trans-Pecos country.
With so few records, the monthly pattern in the data, a small rise in spring and mostly empty months otherwise, is too sparse to call a real seasonal trend. It more likely reflects when the handful of surveys that found this mouse happened to run.
Identifying one from a photo takes a careful look: a tail longer than the body and a sharp white patch at the ankle, the same field marks used to sort it out from other deer mice across its Texas stronghold.
Full species profile
