Lankesteriinae

Manzitto-Tripp, Erin A., Darbyshire, Iain, Daniel, Lucinda A. McDade Thomas F. & Kiel, Carrie A., 2022, Revised classification of Acanthaceae and worldwide dichotomous keys, TAXON 71 (1), pp. 103-153 : 140

Lankesteriinae I.Darbysh. & E.Tripp subtr. nov.

– Type: Lankesteria Lindl.

Perennial herbs or shrubs with cystoliths; leaves opposite; inflorescences of dense terminal spikes or thyrses, often with conspicuous imbricate bracts or the bracts linear in some species, paired bracteoles linear and inconspicuous; corolla yellow, orange, or white, salverform, subactinomorphic or with sinus between the two adaxial lobes at a wider angle than the other lobe sinuses, with trifurcating traces to the lobes, filament curtain absent, aestivation left-contort; androecium of 2 stamens plus (typically) 2 staminodes, anthers bithecous, thecae inserted equally on the filament and held at an equal height; stigma capitate, the lobes oblique; capsule 2-seeded, seeds with hygroscopic trichomes covering the surfaces, surface with concentric rings of ridges, the trichomes attached to (and hiding) these ridges (fide Manktelow & al., 2001); pollen 3-porate, triangular in polar view with flattened apertural faces, pores surrounded by a granular circular area, interapertural areas otherwise reticulate.