Oxalis exilis, commonly known as least yellow-sorrel, is a diminutive herbaceous perennial belonging to the Oxalidaceae family. This species is notable for its extremely small stature, making it one of the least conspicuous members of the *Oxalis* genus. Its significance lies in its contribution to the biodiversity of its native habitats and its role as a groundcover in specific ecological niches. The physical characteristics of *Oxalis exilis* are defined by its delicate and compact growth habit. It typically forms a low mat or tuft, rarely exceeding a few centimeters in height. The leaves are trifoliate, meaning each leaf is composed of three heart-shaped leaflets, a characteristic feature of the *Oxalis* genus. These leaflets are typically green, though variations can occur. The flowers are small and typically bright yellow, borne on slender stalks that emerge from the base of the plant. The flowering period can vary depending on environmental conditions but generally occurs during the warmer months. Following flowering, small, capsule-like fruits develop, containing tiny seeds. The root system is generally fibrous and shallow, contributing to its low-growing habit. *Oxalis exilis* is native to a specific geographic region, primarily found in parts of Australia. Its natural habitat is often characterized by sandy soils, open woodlands, and sometimes disturbed areas where it can establish itself in sparse vegetation. While not widely cultivated, its adaptability to well-drained soils and sunny to partially shaded conditions suggests potential for horticultural use in rock gardens or as a miniature groundcover in suitable climates. It generally prefers moist but not waterlogged soil and can tolerate a range of temperatures, though extreme cold or heat may limit its growth. The ecological importance of *Oxalis exilis* is primarily as a component of its native flora, contributing to ground cover and providing a food source for small invertebrates. There is no widespread documented ornamental, agricultural, medicinal, culinary, or economic importance attributed to this specific species. Its diminutive size and subtle beauty are appreciated by those familiar with its native ecosystems rather than for broad commercial or utilitarian purposes. An interesting characteristic of *Oxalis exilis*, shared with many other sorrels, is the presence of oxalic acid in its tissues, which gives the leaves a characteristic sour or tangy taste. This acidity is a defense mechanism against herbivores. Like other *Oxalis* species, the leaves of *Oxalis exilis* can exhibit nyctinasty, folding or drooping at night or in response to touch, a fascinating adaptation for protection or water conservation. Its ability to thrive in seemingly challenging, open environments highlights its resilience and specialized adaptations to its ecological niche.