The Biedouw Valley Hesperantha bachmannii flowers also shown in this Album have these long, narrow leaves sheathing the stem in succession at different heights. The leaves have clearly visible, raised midribs.
The tubes of these flowers are curved, about 10 mm long.
Several of the plants were growing in a shady field of Oxalis in September (Manning, 2007; Leistner, (Ed.), 2000; Bond and Goldblatt, 1984; iNaturalist).