Impatiens kurichiarmalayana Saravanan & Kaliamoorthy, 2022

Saravanan, Thokuluva Santharam & Kaliamoorthy, Seventhilingam, 2022, Two new epiphytic species of Impatiens L. (Balsaminaceae) from the southern Western Ghats, India, Phytotaxa 552 (1), pp. 107-114 : 110-111

Impatiens kurichiarmalayana Saravanan & Kaliamoorthy , sp. nov. ( Figure 2 )

Impatiens kurichiarmalayana is similar to I. mankulamensis K. M. P. Kumar, R. Jagad. & Nagaraj (2017: 281) and I. panduranganii K. M. P. Kumar, R. Jagad. & G. Prasad (2017: 285) in having common characters viz., rosulate leaves, umbellate cyme inflorescence, unequally bilobed wing petals and shorter basal lobes. But differs from I. mankulamensis by having ovate-lanceolate leaves (vs elliptic, lanceolate-oblanceolate in I. mankulamensis ), lateral sepals white with dark purple tinges at the apex (vs white with brown tinges at tip in I. mankulamensis ), dorsal petal white (vs pale purple in I. mankulamensis ), presence of dorsal auricle (vs absence in I. mankulamensis ) and absence of spur (vs present in I. mankulamensis ); Impatiens kurichiarmalayana also differs from I. panduranganii by having white flowers with dark purple spot at the base of the wing petals (vs white with light purple dots in I. panduranganii ), dorsal petal keeled at apex (vs not keeled in I. panduranganii ), distal lobe spreading and broadly obovate (vs not spreading and shoe shaped in I. panduranganii ), lower sepal white with yellow mark at middle and dark brown streaks horizontally (vs white with yellow tinges in I. panduranganii ) ( Table 2 ).

Type:— INDIA. Kerala: Wayanad District, Kurichiarmala Reserve Forest , 11º36’2”N, 75º57’57”E, 1200–1320 m, 11 December 2019, Saravanan & Kaliamoorthy 136030 (holotype & isotype MH!) .

Epiphytic tuberous herbs. Stem simple, erect, to 19.5 cm tall, succulent, yellowish green in lower portion, distally reddish purple, leaves bearing portion greenish, glabrous. Tubers ca 0.9 × 0.5 cm, oblong, pale brownish white. Leaves crowned at top; lamina 0.9–2.6 × 0.4–1.2 cm, elliptic-ovate to lanceolate, obtuse or apiculate to retuse at apex, attenuate at base, apiculate-crenate at margins, light green and hairy only on nerves adaxially, purplish green and glabrous abaxially; lateral nerves 3–4 pairs; petioles 1.1–2.5 cm long, purplish, glabrous. Inflorescence a subumbellate racemes; peduncle 7.5–9.7 cm long, 3–4-flowered, dark purplish red, glabrous. Flowers 1.7–1.9 cm across, white with dark purple spots at base of distal and basal lobes, glabrous; pedicels ca 0.9 cm long, purplish green, glabrous; bracts ca 0.4 × 0.1 cm, ovate to oblong-lanceolate, acuminate and mucronate at apex, concave, pale greenish with purple lines, glabrous; lateral sepals ca 0.5 × 0.2 cm, elliptic-oblong, acuminate and mucronate at apex, slightly concave, mid nerve pale purplish with dark purple apex; dorsal petal ca 0.6 × 0.3 cm, broadly ovate-orbicular, obtuse, concave, margins wavy, dorsally keeled; keel mucronate at apex; mucro ca 0.1 cm long; wing petals unequally 2-lobed, 1.5–1.7 × 0.5–0.7 cm; claw 0.3–0.4 cm long, glabrous; basal lobe much smaller than distal lobe, ca 0.5 × 0.2 cm, triangular-ovate in outline, acute-acuminate at apex; distal lobe ca 1.2 × 0.5 cm, broadly obovate, obtuse to truncate at apex, notched towards inner side much below the apex; dorsal auricle ca 0.1 cm long, triangular, obtuse at apex, yellowish; lower sepal saccate, ca 0.6 × 0.4 cm, ca 0.2–0.3 cm deep, ovate, obtuse and mucronate at apex, white with yellowish mark at middle, and dark purple streaks horizontally; spur absent; stamens ca 0.4 × 0.2 cm, slightly curved; filaments 5, ca 0.3 × 0.1 cm, creamy white; anthers ca 0.1 × 0.1 cm; ovary ca 0.2 × 0.1 cm, glabrous. Capsules 0.7–1.0 × 0.2–0.3 cm, ellipsoid-clavate, greenish, glabrous; seeds minute, 0.1 cm long, sub-globose, pale yellow, with short white hairs scattered all over the surface.

Phenology:—Flowering & fruiting: June–September.

Ecology:—Growing on moss covered wet tree trunks in evergreen forests, in association with Bulbophyllum fischeri Seidenf. (1974: 202) , Eria albiflora Rolfe (1893: 170) and Oberonia brunoniana Wight (1851: 1622) , at an elevation of 1319 m.

Conservation Status:— Impatiens kurichiarmalayana is only known from the type locality with about 10–15 mature individuals. The population is well conserved within the boundaries of protected forest areas. However, considering the lesser number of individuals in a single population size distributed in an area of hardly 0.3 km, the species described here is assessed as Critically Endangered (CE) by applying the criterion d ( IUCN 2019).

Etymology:—The specific epithet is named after the type locality, Kurichiarmala evergreen forests, Wayanad district, Kerala, India.

Notes:— Impatiens kurichiarmalayana shows also similarities with I. travancorica Bedd. (1874: 29) , in having a rosulate leaves, sub-umbellate raceme inflorescence, white flowers with dark purple patches near the base of the wing petals, sub-globose seeds with short hairs all over, but differs by its habit (Epiphytic tuberous herbs in I. kurichiarmalayana vs annual herbs in I. travancorica ), size and shape of the lateral sepals (elliptic-oblong in I. kurichiarmalayana vs obliquely ovate in I. travancorica ), dorsal petal (broadly ovate-orbicular in I. kurichiarmalayana vs cucullate in I. travancorica ), dorsal auricle (present in I. kurichiarmalayana vs absent in I. travancorica ) and spur (absent in I. kurichiarmalayana vs present in I. travancorica ).

Figures

FIGURE 2. Impatiens kurichiarmalayana A) Habit. B) Abaxial view of leaf. C) Flowering branch. D) Flower. E) Lateral view of flower. F) Bract. G) Dorsal petal. H) Lateral sepal. I) Wing petals. J) Lower sepal. K) Androecium. L) Pistil. M) Fruit. N) Seeds. (Photographs by T. S. Saravanan)