Globba paschimbengalensis Y. Ritu & V. Gowda, 2024

Yadav, Ritu & Gowda, Vinita, 2024, Six new species of Globba L. (Zingiberales, Zingiberaceae) from the Eastern Himalayas and Northeast India, PhytoKeys 246, pp. 197-228 : 197-228

Globba paschimbengalensis Y. Ritu & V. Gowda sp. nov.

Fig. 6

Type.

India. West Bengal: Darjeeling district, Latpuncher , 26.9159, 88.4028, elevation 1200 m, 26 August 2022, Y. Ritu, S. Goray VG 2022 WB 3852 (holotype: BHPL!; isotype: ASSAM!) .

Diagnosis.

G. paschimbengalensis is morphologically similar to G. andersonii but differs in having off-white flowers with a faint tinge of yellow, deeply notched ligule with unequal lobes (Fig. 6 C ) reduced or no peduncle vs. white flowers, ligule with equal lobes and with peduncle.

Description.

Lithophyte herbs, 50–70 cm tall including inflorescence height, pseudostem swollen at the base. Rhizomes compact, non-tuberulous, creamish-white. Leafy shoot with 10–12 leaves; sheath ligulate, ligule 0.9–1.1 cm long, bilobed, lobes unequal, margin minutely pubescent; lamina 24–30 × 4–8 cm, sessile, narrowly ovate, base obtuse, apex caudate, margin entire, adaxially pubescent along veins and margins, abaxially glabrous, veins prominent. Inflorescence terminal to the leafy shoot, 8–12 cm long, erect; peduncle absent or reduced; rachis, dark maroon at the base and terminally light green, densely pubescent; bracts 1.6–1.7 × 1.4–1.5 mm, obovoid, pale yellow, pubescent adaxially, glabrous abaxially, persistent; bracteole 5.5–8.3 × 1.9–7.3 mm, ovoid, pale yellow, glabrous. Cincinni 7–10 per inflorescence, each cincinni with 2–5 flowers. Floral pedicel for basal flowers 2–2.5 cm long, for terminal flowers 0.2–0.4 cm, dark maroon, densely pubescent. Flowers 4.2–4.5 cm long, pale dull yellow, recurved; calyx 5–6 mm long, gray-green; floral tube 8.3–10 mm long, off-white tinged yellow, densely pubescent, curved upwards holding the flower upright; dorsal corolla lobe 5–6 × 2.4–2.5 mm, ovate, apex cucullate, off-white tinged green, sparsely pubescent; lateral corolla lobes 4.5–5 × 3–4 mm, ovate, apex acute, off-white tinged green, glabrous; labellum 9–10 × 2.4–2.5 mm, decurrent, sagittate, off-white with orange spot in center, glabrous, labellum notch with echinate structures; lateral staminodes 7.8–8.8 × 2.6–3.2 mm, narrowly ovate, apex acute, off-white tinged faintly yellow, glabrous. Stamen 2.4–2.5 cm long, filament 1.9–2 cm long, off-white tinged yellow, glabrous, arching; anther 4–5 mm long, largely ovate, off-white, crest 0.4 mm long, obtuse, non-appendaged; style filiform, apex broader than base, stigma 3–4 mm long, cylindrical, apex ciliate. Ovary 1.7 × 1.3 mm, ovoid, cream; epigynous glands 2, 1.2– 1.2 mm, linear, cream. Fruit 1.5 cm in diameter, globose, greenish yellow, verrucose, calyx persistent. Bulbils absent.

Distribution and ecology.

G. paschimbengalensis is recorded only from Latpuncher, Darjeeling district, West Bengal, where we observed ca. 30 individuals in an area of an estimated 400 m 2. G. paschimbengalensis is lithophytic, mostly growing along the edge of roads at an elevation of ca. 1200 m. We have observed bumblebees visiting the flowers of this species.

Phenology.

Flowering and fruiting were observed in the month of August.

Etymology.

The species epithet refers to the Indian state of West Bengal, where this species was found.

Informal conservation status.

We have only found one population that was not in a protected area. The population was spread across a 20–25 m 2 area with a total of 60–70 individuals only. We surveyed six potential locations in Darjeeling in a 40 km 2 area around the type locality (Latpuncher) and did not find any population in northern West Bengal. Based on the IUCN (2022) guidelines, we informally assess the status as Critically Endangered according to criteria B 1. (a) (B 1: extent of occurrence is less than 100 km 2, a: = 1 location), and C. ( C: fewer than 250 mature individuals).

Specimens of allied species examined.

G. andersonii : India. West Bengal: Darjeeling Himalaya, around Baghpul, elevation 200–300 m, 6 July 2011, S. Nirola & AP Das 1334 A (holotype: CAL!), Sivok Hill Forest, Near Coronation Bridge in the ghat region, 2 July 2011, Sachin A. Punekar s. n. ( CALI!), elevation 914 m, 15 July 1913 ( E 00095574), Mongpoo, elevation 914.4 m, 12 July 1884, Williams (P 00411420), Mongpoo, 914.4 m, 12 July 1884, Williams (P 00252245), Darjeeling, Pankabari, elevation 762 m, July 1874, J. S. Gamble 8130 ( K 000640559). Sikkim: elevation 305 m, 6 July 1915 ( E 00095573), Regio Trop (P 00686468).

Taxonomic notes.

The new species is similar to one species in inflorescence length, presence of inflorescence bracts, and absence of bulbils. This species differs from G. andersonii in having unequal lobes, deeply notched ligule (vs. equal lobes and slightly notched), absence of peduncle (vs. presence of peduncle), and large lateral staminodes 7.8–8.8 mm (vs. 5–6 mm). The detailed morphological comparisons between G. paschimbengalensis and G. andersonii are presented in Table 2 .

Figures

Figure 6. Globba paschimbengalensis sp. nov. A habit B, C ligule D inflorescence E flower (front view) F flower (side view) G dissected flower, br (bracteole), cl (corolla lobes), an (anther), sty (style with stigma, ovary and epigynous gland), ls (lateral staminodes), la (labellum) H fruit. Photographs by Y. Ritu.