Oncidium pusillum (L.) Reichb.f. Dwarf epiphyte, to 8 cm tall; pseudobulbs lacking. Leaves +/- dense, spreading like a fan, equitant, +/- linear, 2-6 cm long, to 1 cm wide. Inflorescences 1-6 from base of leaves, about equaling leaves, consisting of long scapes, the apices with several acute, strongly compressed, imbricating sheaths; flowers produced in succession from axils of sheaths; flowers 2-2.5 cm long; sepals free, spreading, bright yellow, keeled and apiculate, the dorsal sepal ca 5 mm long, nearly as wide, the lateral sepals 4-5 mm long, 1-1.5 mm wide, hidden by lateral lobes of lip; petals to 8 mm long and 4 mm wide, bright yellow streaked with reddish-brown, the margins undulate; lip trilobate, to 2 cm long and broad, bright yellow, the lateral lobes +/- orbicular, the middle lobe deeply emarginate, the base with an elaborate subquadrate process; column ca 3 mm long, with prominent, denticulate, lateral wings. Fruits ellipsoid, ca 1.5 cm long, with slender ridges. Croat 4157. Rare on BCI, more common elsewhere in Panama. Flowers during most of the year, but principally in the dry season. Known to flower more than once per season since plants often bear both flowers and fruits on separate inflorescences.