The dark-green, thin-lobed calyx of Lobelia anceps is star-shaped, five-pointed and widely spreading at the corolla base. The calyx lobes of the buds in the background are still angled forward at this stage.
The donkey ear shapes of the pair of small upper lobes of the corolla have a few uneven marginal places like misplaced teeth.
The three lower lobes of the corolla are larger with smooth margins, apart from some sinuous, upper parts. These short, winding sections are about symmetrical on the sides of the central lobe, while occurring only on the inside margins of the lateral pair.
Small, yellow-green and dark blue patches are symmetrical at the base of these lobes (Manning, 2007; Pooley, 1998; iNaturalist; http://pza.sanbi.org).