Isoglossa macowanii C.B.Clarke

Monocarpic, herb or dwarf shrub, 0.2-0.7 m tall, branches either bifarious or pubescent on all sides. Leaves broadly ovate to broadly elliptic, glabrescent, (12-)17-29(-35) x (6-)8.5-15(-19) mm, acute or occasionally rounded; base broadly cuneate to rounded; lateral veins 3 to 4. Petiole (1.5-)2.9-11(-20) mm long. Inflorescence terminal and axillary, interrupted, few-flowered; flowers 2 at a node; terminal inflorescence (8-)13-40(-65) x (3-)4.1-7(-10) mm; leaf below inflorescence ovate, (3.6-)5.4-8.7(-11) x (2-)4.1-6(-7.5) mm; bracts with dense glandular trichomes with 3 stalk cells on the outer surface and sparse long eglandular and rare glandular trichomes with 3 stalk cells on the margins; bracts at base of inflorescence broadly lanceolate to ovate, (2-)2.9-8.2(-11) x (0.3-)0.4-3.3(-4.7) mm; bracts next to open flower broadly lanceolate to ovate, (2-)2.5-6.5(-8.2) x (0.3-) 0.4-2.5(-3) mm, acute; lateral inflorescence (6-)9-18(-28) x (2.5-)5.9(-6.5) mm; leaf below lateral inflorescence ovate, (5-)5.2-8.9(-10) x (3.5-)3.8-6.3(-7) mm; bract at base of inflorescence broadly lanceolate, (1.5-)2.6-5.6(-7.5) x (0.1-)0.5-2.4(-3) mm; bracts next to open flower broadly lanceolate, (1.5-)2.3-6.7(-7.1) x (0.6-) 1.1-2.5(-2.6) mm. Sepals narrowly lanceolate, (5-)5.6-7.0(-7.5) x (0.4-)0.5-1.1(-1.3) mm at anthesis, (6.7-)7.1-8.9(-9.2) x (0.3-) 0.6-1.4(-1.5) mm at fruiting, outer surface with rare short and long eglandular trichomes and dense glandular trichomes with 4 to 5 stalk cells, margins with rare short and dense long fine eglandular trichomes. Corolla tube (4.5-)5.4-7(-7.5) x (1.8-)1.9-4.6(-5.5) mm; upper lip (4.5-)5.2-8.6(-9.4) x (4-)4.4-6(-6.3) mm; lower lip (4.5-)5.2-8.8 (-9.5) x (6-)6.2-7.8(-8) mm; ridges on palate 6 or 7. Pollen grains ± 29.8 µm diam. Capsule (8.7-)9-10(-11) x (1.8-)2.1-3.1(-3. 2) mm. Seeds 2-2.2 x 1.4-2 mm.