Larsenianthus wardianus W. J. Kress, Thet Htun & Bordelon, 2010

Kress, W. John, D. Mood, John, Sabu, Mamiyil, Prince, Linda M., Dey, Santanu & Sanoj, E., 2010, Larsenianthus, a new Asian genus of Gingers (Zingiberaceae) with four species, PhytoKeys 1, pp. 15-32 : 20-21

Larsenianthus wardianus W. J. Kress, Thet Htun & Bordelon sp. nov. Fig. 2 Plate 1A

Latin

Nova species L. careyano affinis, a quo minore statura, congestis foliis, inflorescentia radicali in bractea sine foliis, cum paucis floribus in unaquisque bractea differt.

Type.

Myanmar: Kachin State: Myitkyina Township, NW section of Pidaung Wildlife Sanctuary, approx. 15 km. from Myitkyina, 25°34'52" N, 97°14'56" E, understory of evergreen forest. 22 February 2002. W. J. Kress, Thet Htun, M. Bordelon, and Khin Maung Ha 02-7054 (living plant only for cultivation). Plants of #02-7054 cultivated at the Smithsonian Botany Research Greenhouses. 14 April 2010. W. J. Kress 10-8750 (holotype: US!; isotypes RAF!, E!).

Description.

Evergreen herb, medium-size to 125 cm tall; rhizome to 2.0 cm in diameter, fibrous, aromatic, inner color white; tubers present. Leafy shoots 10-20 per plant, erect, densely clumped. Leaves 4-5 per shoot, to 118 cm in total length; basal leaf sheaths reddish and glabrous, ca. 30 cm in length × 5 cm in width; sheathing petioles to 52 cm in length × 1.5 cm in diameter, glabrous, green and clasping stem, margin slightly revolute; ligule small, 10 mm in length × 1 mm in width, not lobed, truncate on petiole, papery and ephemeral disappearing in mature leaves; lamina 67 cm in length × 14 cm in width, ovate, green and glabrous above, lower midrib green and glabrous, base long attenuate onto petiole, slightly subequal, apex acuminate, adaxial surface dark green. Inflorescence basal on leafless shoot, erect to 33 cm in height; peduncle 20 cm in length × 1.0-1.5 cm in diameter, glabrous, lower sheaths red, upper sheaths green; spike ovoid, 6-10 cm in length × 4-5 cm in diameter; rachis straight; inflorescence bracts about 40 per inflorescence, 1-2 lower bracts sterile, bracts 3.7 cm in length × 2.4 cm in width at base of inflorescence, 2.0 cm in length × 1.8 cm in width distally, spirally arranged and imbricate, not pouched, held at 40° from vertical axis, glabrous, bright green with reddish apex, margins smooth; bracteoles not tubular, 2.1 cm in length × 1.6 cm in width, glabrous, pale white with reddish apex. Flowers conspicuous, 3-4 per bract; calyx tubular, 1.5 cm long, tri-lobed with central lobe shortest, pale yellow to pink; floral tube 3.2 cm in length × 2.0 mm in diameter, reddish pink, externally glabrous with scattered unicellular papillate hairs inside, lobed with each lobe 1.4 cm in length, reflexed; lateral staminodes 3.0 mm in length × 2.0 mm in width, cup-shaped, glabrous, red; labellum 2.2 cm in length × 3.0 mm in width at apex, linear to spatulate, not lobed, red basally with yellow apex, glabrous; fertile stamen with filament 2.1 cm long, red at throat of corolla becoming yellow distally, glabrous; anther 3.0 mm in length × 2.0 mm in width, without a crest; pollen pale yellow; epigynous glands two, linear; stigma minute, <1 mm across, white, extending slightly beyond anther; ovary trilocular, 2.0 mm in length × 2.0 mm in width, pubescent, white to cream colored. Fruits and seeds unknown.

Distribution.

Known only from the type locality in Kachin State, upper Myanmar.

Ecology.

This species is found in the understory of evergreen forests dominated by members of the family Dipterocarpaceae in the foothills of the Himalayas.

Etymology.

Named for Francis Kingdon-Ward, the British plant collector who extensively explored Upper Burma in the first half of the twentieth century and who inspired the authors of this species in their work in Myanmar ( Kress et al. 2003, Kress 2009).

Other specimens examined.

Known from the type collection in Padaung National Park west of Myitkyina, Kachin State, Myanmar, as well as cultivated material (Smithsonian Botany Research Greenhouse GH-2002-050) collected at the type locality.

Figures

Plate 1. Inflorescences with flowers of A Larsenianthus wardianus W. J. Kress, Thet Htun & Bordelon B Larsenianthus careyanus (Benth.) W. J. Kress & Mood C Larsenianthus assamensis S. Dey, Mood, & S. Choudhury D Larsenianthus arunachalensis M. Sabu, Sanoj & T. Rajesh Kumar. All photos by the authors.

Figure 2. Larsenianthus wardianus W. J. Kress, Thet Htun & Bordelon. A overall habit B leaf base with petiole and ligule C inflorescence D inflorescence bract E bracteole F calyx, spread open G flower, lateral view H flower, front view I flower, semi-lateral view with corolla tube cut away to show epigynous nectaries and style J base of flower, cut-way view to show style, and ovary K anther with slightly protruding stigma L ovary, transverse section. Line drawing by Alice Tangerini from plants in cultivation; Botany Research Greenhouse Accession 02 - 7054 and US National Herbarium voucher W. J. Kress 10 - 8750.