Corresponding author: M. Sabu (
Academic editor: W. John Kress
A new species of
Intensive botanical explorations for the revision of Indian
The new species,
Distinguishing morphological characters of
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Habit | slender, spreading | robust, clump forming |
Rhizome | slender and stoloniferous | stout and non-stoloniferous |
Lamina | oblong-lanceolate, 15−30 × 3−7.5 cm | lanceolate to elliptic-lanceolate, 32−41 × 6.5−8 cm |
Petiole | 0−2 mm long | 2−8 mm long |
Leaves | glabrous to puberulous beneath | tomentose beneath |
Ligule | 2.5−4.5 cm long and half deciduous | 4.5−9 cm long and persistent |
Corolla tube | shorter than labellum | longer than labellum |
Labellum | 3−3.5 × 2.3−2.8 cm, trilobed, maroon stripes on yellow ground | 1.4−1.5 × 1−1.2 cm, not trilobed, uniformly yellow |
Lateral staminodes | 2−5 mm long | absent |
Stamen | 1.7−2.1 cm long, crest truncate, 1.5−1.6 × 0.3−0.4 cm | 1.1−1.2 cm long, crest emarginate, |
The species shows similarity with
Clump forming herb. Rhizome non-stoloniferous, stout, robust, 2−4 cm thick, robust, creamy-white inside, sheathed with scales; scales ovate to triangular, chartaceous, c. 1.8 × 2 cm, apex nearly rounded, pubescent externally. Leafy shoots 200−400 cm tall, robust, clump forming; sheath 2.5−4.5 cm wide at base, green, densely pubescent externally. Leaves 14−20 per leafy shoot; lamina lanceolate to elliptic-lanceolate, 32−41 × 6.5−8 cm, base cuneate, margin slightly straight, apex acuminate to 3 cm long, puberulous to glabrous and green on upper surface, tomentose and pale beneath; midrib hispid beneath; veins appressed above; petiole 2−8 mm long, pale green, wooly tomentose. Ligule entire, lanceolate, 4.5−9 cm long, chartaceous, drying, persistent, apex acute, pubescent to tomentose externally, glabrous within. Inflorescence 7−15 cm long, many flowered, arise from the rhizome under soil; peduncle 3.5−7.5 cm long. Bract oblong, 3−4.7 × 1.6−2.1 cm, coriaceous, red, margin ciliate, apex slightly emarginate, pubescent externally, glabrous internally. Bracteole tubular, 2-lobed, 2.2−2.5 × 0.5−0.6 cm, unequally split, membranous, red, margin ciliate, apex acute, pubescent externally, glabrous within. Flower 4.7−5.2 cm long, yellow; pedicel 5 mm long. Calyx 2 or 3-lobed, 2.4−2.8 × 0.4 cm, pale red, membranous, split nearly equal, margin ciliate, apex acute, pubescent externally, glabrous within. Corolla tube 2.5−3 cm long, c. 4 mm wide at mouth, pale yellow, pubescent externally, glabrous internally except near mouth; dorsal corolla lobe oblong, 1.4−1.6 × 0.7−0.8 cm, yellow, margin ciliate, apex hooded, ecuspidate, pubescent externally, glabrous within; lateral corolla lobes oblong, 1.4−1.6 × 04−0.6 cm, yellow, margin ciliate, apex nearly rounded, one side slightly folded, pubescent outside, glabrous within. Labellum obovate to rhomboid, 1.4−1.5 × 1−1.2 cm, uniform yellow, margin entire, apex clefted, pubescent inside along the median part. Lateral staminodes absent. Stamen 1.1−1.2 cm long; filament 4−5 × 2.5−3 mm, pale yellow, broader towards base, rarely minutely pubescent; connective rarely pubescent externally; crest inconspicuous, c. 3 × 1 mm, yellow, apex emarginate, rarely puberulous; anther thecae oblong, 6−7 mm long, creamy-white, base nearly rounded, apex rounded, pubescent; dehiscing throughout their length. Epigynous glands 2, oblong, 3−4 mm long, cream coloured, apex truncate, rarely puberulous. Ovary globose, 4−5 × 4 mm, densely pubescent externally; locules 3; ovules many on axile placentae; style 3.4−3.7 cm long, pubescent towards tip, glabrous towards base; stigma, tubular, c. 1 mm across, pale yellow, mouth ciliate, opening terminal. Capsule 8−10 per spike, globose, 2−3 × 2−3 cm, red, echinate, spines stout, pubescent externally, calyx not persistent. Seeds many, slightly oblong, 4−5 × c. 3 mm, black, aromatic, arillate, glabrous; aril white.
March−November.
Known only from type locality, Silent Valley National Park, Western Ghats, Kerala in the evergreen forest above 1210 m.
the specific epithet
Critically endangered (CR B1ab(ii,iii)+B2ab(i,ii)). The taxon has been evaluated against the criteria as described in IUCN (2001). The area of occupancy is estimated to be less than 10 Km2 and its habitat is severely fragmented, and known to exist only in a single location. A continuous decline in quality of habitat and extent of occurrence is noticed. Major threat to the population are forest fire and clearing of trekking path in the forest which cause damage to the existing population.
INDIA, Kerala: Palakkad District, Silent Valley National Park, 3 km from Walakkad towards Sispara, 24 September 2008,
We are thankful to the Department of Science and Technology, New Delhi, for financial support. The authors are grateful to Department of Forest, Govt. of Kerala for providing necessary forest permission. We are also thankful to Dr Mark Newman, RBG, Edinburgh for critical comments on the species. We are thankful to Mr Shameer MC Department of Botany University of Calicut for the helps during specimen collection.