Description from Flora of China
Plectranthus calcaratus Hemsley, Hooker's Icon. Pl. 27: t. 2671. 1900; Hemslea calcarata (Hemsley) Kudo.
Herbs perennial, mostly sparsely rust colored, moniliform glandular villous. Stems ascending, ca. 25 cm tall, much branched, base trailing; branches and stem slender, purple-red. Petiole 4-9 mm; leaf blade ovate to ovate-oblong, 1.4-5 × 0.7-2.6 cm, papery, sometimes subglabrous, adaxially appressed minutely hispid, abaxially appressed minutely hispid on veins, base cuneate-decurrent, margin crenate, apex acuminate to acute. Verticillasters in loose terminal racemes; bracts ca. 3.5 × 3 mm, apex abruptly acute. Pedicel 3-5 mm. Calyx broadly funnelform, ca. 2 × 4.5 mm, villous, golden glandular, glabrous inside; middle lobe of upper lip ca. 1.6 mm wide, lateral lobes obliquely triangular-orbicular; lower lip ca. 1.6 × 1.2 mm, apex emarginate. Corolla blue, ca. 1.8 cm, glandular villous, spur ca. 1/2 as long as corolla, throat ca. 4 mm wide; upper lip ca. 5 mm, lobes triangular-ovate, middle lobe somewhat larger than lateral lobes; lower lip slightly longer, ca. 1.6 mm wide, slightly concave. Anthers blue. Style capitate. Nutlets gray-brown, ca. 1.2 mm in diam. Fl. Sep-Oct, fr. Oct-Nov.
Valleys, dense or sparse forests, streamsides; 800-1600 m. Guangxi, Yunnan [Myanmar].