This species differs from 1. H. elongatum in the following respects:
Leaves (main stem) linear to narrowly oblanceolate or oblong, apex obtuse to rounded; leaves (axillary) withapex always rounded. Inflorescence up to 12 nodes, 15–c. 20 mm long, sometimes with 1–2 pairs of flowering branches below. Sepals equal, not imbricate, 2–4 × 0.6–1.2 mm, narrowly (rarely rather broadly) oblong to narrowly triangular, obtuse to subacute, almost always all regularly gland-fringed, with glands sessile or margin subdenticulate. Petals 5–18 × 2.5–8 mm, 2–5.5 × sepals. Capsule not or scarcely rostrate.