Hedbergia decurva

Hedbergia decurva is a shrub covered in sticky glandular hairs and few non-glandular hairs. It reaches 50–200 cm (20–79 in) in height, having thin, woody, upright, sparsely branching stems. The mostly upright, narrowly ovate seated leaves of 8–36 mm (0.31–1.42 in) long, have rounded teeth along the margins that are mostly rolled downwards, and are set in opposite pairs. The shortly stalked flowers are set in a raceme towards the tip of the stems in the axils of leaflike bracts. The sepals are merged into a calyx with 4 lobes with deeper incisions on the midline and shallower incisions left and right. The yellow to yellowish brown petals are merged into a strongly mirror-symmetric corolla, with a long, in the upper part distinctly curved tube, topped by a helmet-shaped upper lip that encloses the anthers and a spreading, three-lobed lower lip that has two bulges in front of the throat of the tube. The filaments of the 4 stamens have largely merged with the upper lip of the corolla and are topped by shaggy anthers that each have 2 district spines at their lower end. The style is on top of a shaggy ovary and tipped by a club-shaped stigma. The narrowly elliptical seeds are 0.6–1.9 mm (0.024–0.075 in) long, with several ribs along their length. The species probably has 14 pairs of homologous chromosomes (2n=28).^[3]

Hedbergia decurva can be distinguished in having a curved upper corolla tube and spines on the lower end of the anthers, whereas Hedbergia longiflora has a straight corolla tube and acute but not spined anthers.^[3]