The plant is native to the west coast of North America from British Columbia to central California from the California Coast Ranges across to the Sierra Nevada. It grows in moist open habitat such as spring-fed grasslands.
Triphysaria pusilla is an annual herb producing a hairy brownish or purple-colored, multi-branched stem up to about 20 centimeters in maximum height. Like many species in its family, it is a facultative hemiparasite on other plants, attaching to their roots via haustoria to tap nutrients and water.
Its leaves are greenish, red or purple because of the anthocyanin pigments that the plants produce. They are up to 3 centimeters long and divided into a few narrow, pointed lobes.
The inflorescence is a spike of minute, tubular flowers. Each flower has a beak-like yellow or purple upper lip and a wider lower lip which is divided into three tiny yellow or purple pouches. To increase the chances of cross pollination, at any point of time during the flowering season, only three flowers will have matured on each individual plant. Two of these flowers mature their anthers first while the remaining flower matures its stigma.
- "Triphysaria pusilla". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 15 December 2015.
- "In defense of plants - Ants As Pollinators?". October 11, 2017.
- Kincaid, T. (1963). "The ant-plant, Orthocarpus pusillus, Bentham". Transactions of the American Microscopical Society. 82 (1): 101–105. doi:10.2307/3223826. JSTOR 3223826.
Media related to Triphysaria pusilla at Wikimedia Commons
- Jepson Manual Treatment: Triphysaria pusilla
- Washington Burke Museum
- Triphysaria pusilla — U.C. Photo gallery