Monographs Details: Borreria capitata var. capitata f. glabra Steyerm.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Description:Latin Diagnosis - A B. capitata var capitata f capitata caulibus foliisque omnino glabris vel angulis caulis pubescentibus recedit; foliis lineari-lanceolatis vel oblanceolatis 6-9 × (0.3-) 0.7-1 cm; stipularum vaginis dense breviter pubescentibus setis 7-8 parce setulosis vel fere glabris 4-10 mm longis, nervis lateralibus prominentibus utroque latere 3-4 subtus elevatis; capitulis 15-20 mm diam.

Discussion:This glabrous variation is similar to the typical form of B. capitata except for the completely glabrous lower side of the leaves including the midrib and lateral nerves. It may be differentiated from the glabrous-leaved and glabrous-stemmed B. capitata var tenella by the generally broader leaves with more numerous and more prominent lateral nerves, the flowering heads averaging larger, and the stipular bristles averaging longer.