Olive Grass Mouse

About the Olive Grass Mouse

Abrothrix olivacea, also known as the olive grass mouse or olive akodont, is a species of rodent in the genus Abrothrix of family Cricetidae. It is found from northern Chile into southern Chile and Argentina, including the islands of Tierra del Fuego. It is prone to large swings in population size.

The olive grass mouse is a small rodent with a total length of about 17 cm (6.7 in). The upper parts are greyish-brown, sometimes slightly yellowish around the snout, and the underparts are pale to mid-grey. A scaffold-level genome assembly of Abrothrix olivacea was published in 2026. The genome size is approximately 2.25 Gb, with a BUSCO completeness of 98.6%. A total of 21,476 protein-coding genes were identified. This was reported as the first genome assembly for a member of the sigmodontine tribe Abrotrichini.

Abrothrix olivacea has had a complex history in both of the genera Akodon and Abrothrix, and includes at least 27 synonyms. A few, including markhami, mansoensis, and xanthorhinus have been viewed as valid species until recent years, and several subspecies are still recognized, including Abrothrix olivacea markhami. Wikipedia →