Drosera riparia
Range: South-central Bahia, Brazil
This relatively newly identified species is one of the smallest known in the D. villosa complex, a group known for rather large, showy long-leaved plants. It is found solely in the Chapada Diamantina mountain ranges of south-central Bahia at elevations of 850-1850 meters, where it grows in quartz and limestone sandy soils or sphagnum pads along the wet margins of river and stream banks (for which the species is named) or canyon walls and seeps. Plants reach commonly 4, rarely to 10 cm tall on narrow stems, topped by a rosette comprised of erect to semi-erect narrow spatulate-oblong leaves up to 11 cm in diameter. Petioles are parallel to slightly tapered, typically just over half the total leaf length and sparsely pilose on the abaxial surface. Lamina are ovoid to narrow oblong in shape, often slightly curved. Color is bright green to yellow with red tentacles, flushed red in the lamina, or may be tinged in crimson throughout. Scapes reach up to 20 cm in height, and are typically glabrous, supporting up to on average 9 flowers. Blooms are relatively small at 1 cm across, composed of broad obovate and pale pink petals. This species can be distinguished from its relatives by the presence of notably long petioles compared to the lamina, and by the lack of most hairs or glands across the petioles, scapes, and sepals as well as the small flower size.
Cultivation: grow in a 2:1 sand/peat or 1:1 sphagnum/perlite soil, kept very moist to wet but well aerated and humid, with day temps of 65-85°F, night temps of 50-65°F, year round. Sow seeds on soil surface, and grow in strong artificial light to full sunlight.
Lifespan and reproduction: perennial. Reproduces through seeds, and can be grown through leaf or root cuttings.
Sources: Gonella et al. (2014). Exhuming St. Hilaire: revision of the Drosera villosa complex (Droseraceae) supports 200 year-old neglected species concepts. Phytotaxa 156(1): 1-40.