Strobilanthes sripadensis

Description: — Subshrub, slender, up to 50 cm high. Stems terete, glabrous, woody, slightly swollen at node, transverse ridges not prominent. Leaves opposite, unequal in each pair; petioles 1.4 – 2.5 cm long, glabrous; blades oblong to elliptical, 6.2 – 10.5 × 2.1 – 3.6 cm, base cuneate, margin entire or slightly sinuate, apex obtusely short acuminate, adaxially dark green, glabrous with numerous cystoliths, abaxially paler green, glabrescent, venation camptodromous, lateral veins 5 – 7 pairs, prominent on both surfaces, tertiary veins inconspicuous. Inflorescences of bracteate heads, terminal or axillary opposite pairs on short leafy branchlets; heads oblong, few-flowered, 1.3 – 5.1 × 1.1 – 1.9 cm, glabrous; peduncles 1.8 – 4.7 cm long; flowers sessile; rachis glabrescent. Bracts broadly oblong, 0.5 – 1.0 × 0.2 – 0.6 cm, apex obtuse, slightly concave, the outermost ones longer than the inner ones, pubescent on adaxial surface and margin towards the apex, then densely glandular pubescent on mature capsule. Bracteoles linear-oblong, 7.9 – 9.1 × 1.9 – 2.0 mm, apex obtuse, pubescent along margin towards the apex, then glandular-pubescent. Calyx five-lobed to about half of the length; lobes linear, 8.9 – 9.0 × 1.9 – 3.0 mm, apex acute, margin pubescent towards the apex, then densely glandular-pubescent when fruiting, persistent. Corolla 1.4 – 1.5 cm long, white with prominent dark purple lines at throat, outside glabrous, inside glabrous except at the place of the insertion of the stamens, tube very narrowly cylindrical for 1.3 – 1.4 cm, then abruptly inflated and campanulate, flower diameter 2.1 – 2.3 cm, lobes obovate, 10 – 13 × 4 – 8 mm, spreading. Stamens 4, exserted, didynamous; filaments glabrous except for a few hairs at the base, shorter pair 12.9 – 13.1 mm long, longer pair 18.2 – 19.0 mm long; anthers bithecous, subsagittate, dorsifixed near to the base, anthers yellow brown. Staminode 1. Ovary two locular, oblong-elliptic, 2.5 – 3.0 mm long; style exserted, slightly curved, 1.7 – 2.0 cm long, glabrous; stigma unlobed. Capsule 8 – 9 mm long, 2 – 3 mm wide, narrowly oblong-ellipsoid, glabrous, 4 - seeded. Seeds, ca. 1.5 mm broad softly pubescent. Pollen Morphology: — Pollen grains of S. sripadensis (Figure 4) are spheroidal, 47 – 56 × 2.7 – 2.9 µm, 3 - colporate, equatorial. Carine and Scotland (1998) observed the pollen morphology of 25 Strobilanthes species from Sri Lanka. They recognized 13 ellipsoid pollen types and 12 spheroidal pollen types for Sri Lankan Strobilanthes species. Pollen morphological characters showed a great variability among Sri Lankan Strobilanthes species.