Ottelia guanyangensis Z.Z.Li, Q.F.Wang & S.Wu., 2018

Li, Zhi-Zhong, Liao, Kuo, Zou, Chun-Yu, Liu, Yan, Hu, Guang-Wan, Wang, Qing-Feng & Chen, Jin-Ming, 2018, Ottelia guanyangensis (Hydrocharitaceae), a new species from southwestern China, Phytotaxa 361 (3), pp. 294-300 : 299-300

Ottelia guanyangensis Z.Z.Li, Q.F.Wang & S.Wu. sp. nov. ( Fig. 2 )

The new species bear a resemblance to Ottelia balansae in possessing bisexual flowers, three stamens, but differs in having hexagonal-cylindric ovary (vs. triangular-cylindric), hexagonal-cylindric and winged fruit (vs. narrowly elliptic, unwinged), trinerved with obvious cross veins (vs. basal veins), and 2–5 flowers each spathe (vs. 3–11).

Type: — CHINA. Guangxi: Guilin City , Guangyang County, 25°44′ N, 111°13′ E, elev. 493 m, 20 August 2017, Z. Z. Li & S. Wu Otte 015 (holotype HIB!; isotype HIB!) .

Perennial herb. Rhizome, short. Leaves entirely submerged, dark green and opaque, linear, 15–50 × 4–6 cm, base rounded, apex acute; longitudinal veins 9; midrib obvious, stretched to the apex, becoming trinerved with obvious cross-veins at a distance of 4–6 cm from the base; petiole smooth, dark green, 8.0–13.0 cm long, the base expanded into a sheath. Spathe oblate, 3.0–4.5 × 2.5–3.0 cm, warty along edges, longitudinally ribbed and winged on the lateral margins, containing 2–5 flowers; Flowers bisexual; sepals reddish brown, 1.0–1.5 × ca. 0.5 cm, with conspicuous longitudinal ribs; petals white with yellow base, obovate, 1.5–2.0 × 2.0– 2.5 cm, with longitudinal pleats; stamens 3, opposite to sepals, anthers elliptic, connective obscure, filaments 5.0–7.0 mm long; glands 3, 0.5–1.0 × 0.5–1.5 mm, opposite to petals, pale yellow to milky white. Ovary hexagonal-cylindric, 4–5 cm long, with 3 carpels; styles 3, pale yellow, slender and hairy, 1.0– 1.3 cm long, stigma bifid, divided entirely to base; stigmas 6, liner and hairy, ca. 7 mm long. Fruit a hexagonal-cylindric capsule, with 6 wings, dark green to red brown, with persistent calyx, 4.0– 7.5 cm × ca. 6.5 mm, always longer than spathe. Seeds numerous, usiform, ca. 1.5 mm long, both ends hairy. Pollen, subglobose, ca. 45 μm in diam., with spiny granules.

Distribution and habitat:— Ottelia guanyangensis presently is known only from Guanyang County, Guangxi Province, China. It has been found in two localities within Guanyang County. It grows along rivers or streams, where the water depth is less than 1.5 m. It also is likely to disperse to adjacent areas, due to its occurrence in the complex river systems, which promote the dispersal of aquatic plants.

Phenology:—The new species was found in flower from April to October.

Etymology:—The epithet is derived from the name of Guanyang County, which is the type locality.

Other specimens examined (paratypes):— CHINA. Guangxi, Guilin City , Guanyang County, elev. 387 m, 8 October 2017, Z. Z. Li Otte 016 ( HIB!) ; Guanyang County, elev. 388 m, 2 April 2017, 450327170402006 LY ( IBK!)

Figures

FIGURE 2. Ottelia guanyangensis.A. Plant habitat. B. Plant habit and flowering plant. C. Bisexual flower with red brown sepal. D. flower individual. E. Fruit: Hexagonal-cylindric with wings. F. Leaf: Triplinerved with obvious cross veins. G. Character of pollens by SEM.