Related to U. leandrii, this also forms a small tree with straight, vertically ascending branches crowned by a cluster of palmately lobed leaves. From the axils of these leaves the bright yellow, dark-throated flowers are produced in abundance. Lavranos records over 100 flowers per branch produced over the flowering period. The specific epithet alludes to the distinctive spade-shaped, winged fruits, the broad, flattened margins being as much as 1.5 cm. wide. Clustered toward the center of the fruit are two rows of five pairs of short projections, each tipped with a pair of recurved barbs that aid in dispersal by animals unfortunate enough to become entangled in them. The species is described and well-illustrated in Haseltonia 3: 83 - 88 (1995) and properly typified in this journal the following year (vol. 68: 82). HBG 85220, from controlled pollination of the type plants, Röösli and Hoffmann 2494, collected Dec. 25, 1994, on limestone, in forest N of Mahajanga, Madagascar. $60.
Published in the Cactus and Succulent Journal, Vol. 74 (2), March - April, 2002