Chlorophytum assamicum D.Borah & A.P.Das, 2019

Chlorophytum assamicum D.Borah & A.P.Das View in CoL sp. nov. ( Fig. 1 View FIGURE 1 )

The new species is quite similar with closely allied C. tuberosum and C. arundinaceum in their habit, shape and size of leaves, type of inflorescence and overall flower structure. It can be easily distinguished from these two species for the presence of subterranean rhizomatous rootstock bearing narrowly fusiform roots (vs. broadly fusiform in C. arundinaceum and ellipsoid to cylindrical oblong in C. tuberosum ), the presence of a sterile bract (vs. absent in both) in the peduncle, the long pedicel without any articulation (vs. pedicel with an articulation at middle or below middle in C. arundinaceum and below middle in C. tuberosum ), the indistinct venation in perigone segments (vs. 3-veined in outer and 5-veined in inner perigone segments in C. arundinaceum and 7-veined in outer as well as inner perigone segments in C. tuberosum ), the filament slightly longer than anthers as well as dehiscing by apical pores (vs. shorter or equal to anthers in C. arundinaceum and shorter than anthers in C. tuberosum and dehiscing by longitudinal slits in both).

TYPE: — INDIA. Assam: Sonitpur district, Behali Reserve Forest , 26°54’03’’N 93°15’45’’E, elev. 90 m, 26 May 2018, D. Borah & P. Kafley 054 (holotype, CAL!; GoogleMaps isotype, ASSAM!) GoogleMaps .

Perennial terrestrial rosulate herb, erect or sub erect leaves to 45 cm long. Rhizomatous rootstock subterranean, horizontal to oblique, 2.5–6 × 1.2–1.5 cm; roots 30–60, 10–28 cm long, 5–8 mm thick, narrowly fusiform, white; slender secondary roots mostly produced from below the fusiform area. Cataphyll one with a very small limb. Leaves sessile, rosulate, 6–12 to a plant, spreading, imbricating at base; leaf blade 15–45 × 5–6 cm, broadly lanceolate, margin entirehyaline, slightly undulate, acuminate, base gradually narrowed down, green, leathery, both surfaces glabrous; veins 24–28, parallel, main vein channelled on upper surface. Scape solitary, unbranched, peduncle 17–25 cm long, terete, glabrous, without intermediate node, raceme 5–6 cm long, about 1/4 th length of the scape; lowermost bract sterile, larger than others, 6–7 × 0.25–0.35 cm, green at the beginning but soon turning blackish-brown, subulate, entire, long-acuminate, glabrous. Fertile bracts ovate-acuminate, carenate, whitish, 1–2 × 0.5–0.6 cm, thinly herbaceous, margin hyaline-translucent, with 5 greenish veins, glabrous, soon withers. Bracteoles 3, recurved, triangular-ovate, whitish, turning blackish-brown in flower, 1–5 × 1–3 mm. Pedicels 1–3 to a node, 0.6–0.8 cm long, terete, glabrous, greenish white, without an articulation. Flowers 1.3–1.8 cm across. Perigone segments in two whorls, free, white, 1.1–1.3 × 0.3–0.4 cm, ovate lanceolate, obtuse, veins obscure. Stamens in two whorls, 0.8–1.1 cm long, erect; filaments 0.5–0.6 cm long, terete, white, glabrous, slightly longer than anthers, smooth; anthers 0.3–0.4 cm long, yellow, dehiscing with one apical pore on each side of the minute terminal appendage, later furrowing below. Ovary terete, 2.5–4 × 1.9–2 mm, light greenish, 3-lobed; style 1, terminal, 1–1.4 cm long, straight, white, glabrous; stigma elongate, finely papillose. Immature capsule green, triquetrous, sulcate, ca. 1.2–1.5 cm long. Seeds not observed.

Phenology: — Flowering from April to May, fruiting from May to June.

Etymology: — The specific epithet refers the Indian state of Assam where the new species was collected.

Distribution: — Chlorophytum assamicum grows in dense mixed deciduous forests of Behali Reserve Forest, Sonitpur district of Assam in Northeast India at elevation about 90 m a.s.l. Grows in association with Sterculia lanceolata var. coccinea (Jack) Phengklai , Chloranthus elatior Link , Coffea benghalensis B.Heyne ex Schult. , Clerodendrum laevifolium Blume , Dalhousiea bracteata (Roxb.) Graham ex Benth. , Gnetum gnemon L., Dracaena petiolata Hook.f. , Mycetia nutans (R.Br. ex Kurz) Razafim. & B.Bremer , Tropidia curculigoides Lindl. , Tacca integrifolia Ker Gawl. , Amischotolype hookeri (Hassk.) H.Hara.

Conservation status: — The IUCN status for the new species was “Not Evaluated” as only two populations within a diameter of 1 km were detected. One population had 10 plants and the other had nearly 20 individuals. The habitat is a natural reserve forest, and due to the increasing human pressure for collection of firewood as well as other non-timber forest products, the population is under severe threat.