Strobilanthes kunthiana (Nees) T.Anderson ex Benth.

Carine, M., Jake M. Alexander, & Scotland, R. (2004). A Revision of the Strobilanthes kunthiana-Group (Phlebophyllum sensu Bremekamp) (Acanthaceae). Kew Bulletin, 59(1), 1-25. doi:10.2307/4111071

Type

E. Notan, Nilghiris, s. coll., Wall. Cat. 2367, (holotype: K-W!).

Morphology Stem

Stem glabrous to sparsely pubescent, usually only so in the grooves and on nodes; lenticels and leaf scars sometimes prominent

Morphology Leaves

Leaves elliptic to obovate, 9 - 65 x 4 - 39 mm; base shortly decurrent, symmetrical; apex very short acuminate; margins subentire to prominently serrate; abaxial surface sparsely to densely covered with a white farinose indumentum, adaxial surface glabrous or sparsely covered with stout tapering hairs; veins 4 - 10 pairs, both primary and secondary veins prominent on abaxial surface, somewhat less so on adaxial surface; petiole 0 - 5.4 mm long, glabrous or with stout tapering hairs, especially along margins

Morphology Reproductive morphology Inflorescences

Inflorescence broad uninterrupted spikes, 12 - 43 x 6 - 12 mm; axis sparsely to densely covered in short white hairs

Morphology Reproductive morphology Inflorescences Bracts

Bracteoles 3.7 - 4.4 mm long Bracts broadly ovate or rarely elliptic, 9.2 - 12.8 x 2.3 - 5.2 mm, slightly longer than calyx; apex acuminate; abaxial surface and margins with prominent short white hairs, adaxial surface glabrous

Morphology Reproductive morphology Flowers Calyx

Calyx with 2 lobes typically shorter than the rest, fused for 0.3 - 0.4 of the total length at anthesis; lobes narrowly ovate, 5.8 - 13.9 mm long, apex acuminate; abaxial indumentum as bracts, adaxial surface glabrous or rarely with simple hairs

Morphology Reproductive morphology Flowers Corolla

Corolla pale blue to mauve; tube 3.4 - 4.4 mm long; throat campanulate, 9.5 - 11.4 mm long; lobes equal, somewhat overlapping, oblong, 2.8 - 5.3 x 2.1 - 3.7 mm, apex broadly obtuse or often emarginate; outer surface with short, reflexed hairs

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens included; anthers 1.3 - 1.8 mm long; filaments 5.1 - 7.1 mm long, sparsely pubescent below for approximately half the length

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary 1.3 - 1.8 mm long, apex pubescent

Morphology Reproductive morphology Flowers Gynoecium Style

Style 9.3 - 10.1 mm long, sparsely pubescent

Morphology Reproductive morphology Flowers Gynoecium Stigma

Stigma 3.0 - 4.6 mm long with short white hairs

Morphology Reproductive morphology Fruits

Fruit a narrowly elliptic capsule, 10.0 - 12.0 mm long, hairy at apex

Morphology Reproductive morphology Seeds

Seeds c. 2.5 mm long.

Distribution

India, Kerala and Tamil Nadu.

Ecology

On bare slopes, ravines etc. above 1800 m.

Phenology

Flowering May -January; fruiting January - March. Whilst most plants are in flower during the twelfth year of the cycle, some flowering does occurs in the years before and after the main bloom (Matthew 1971).

Note

Strobilanthes kunthiana is readily distinguished from other members of the group by the farinose indumentum on the lower leaf surface. It is perhaps the best-known species of Strobilanthes and its semelparous life history is well documented with mass flowering events recorded every twelve years since 1838 (Robinson 1935; Matthew 1971).

Vernacular

The name Nilgiris ('Blue Mountains') may be attributed to the mass flowering of this species.

Conservation

This species formerly occupied extensive areas of the Western Ghats, dominating the hillsides and covering them in blue blossom during flowering years. However, as Matthew (1999) notes, changing land management practices have seen a considerable reduction in the abundance of this species.

Use

Mass flowering events of S. kunthiana were landmarks in the lives of the hill tribes of the Western Ghats (Matthew 1971) and continue to generate significant popular interest.