Slender Lousewort is a graceful annual herb found on alpine meadows on mountain slopes in the Himalayas at altitudes of 2000-4000 m. It is a herb growing to more than 1 m tall, drying to dark color. Stems with 3 or 4 lines of hairs. Stems are many branched, and the branches are in whorls of 4-6. Basal leaves wither early. Stalkless stem leaves, mostly 1-3 cm, are pinnately divided into 6-9 pairs of oblong toothed segments. Inflorescences are raceme-like, in separated bunches. The bracts (modified leaves just below the flowers) are leaflike. The sepal cup is cylindric, 5-7 mm, with 5 lobes. Flowers are purplish pink, 1.2-1.5 cm, with a slender flower tube. Upper lip of the flower is sickle-shaped, swollen in the middle with a long almost straight beak. Lower lip is very variable, rounded or 3-lobed, and smaller than the upper lip. Capsule is broadly ovoid, terminated abruptly by a small, distinct point. Flowering: August-September