Utricularia lihengiae C. L. Long & Z. Cheng, 2021

Cheng, Zhuo, Fang, Qiong, Wang, Fei & Long, Chun-Lin, 2021, Utricularia lihengiae (Lentibulariaceae), a new species from Northwest Yunnan, China, PhytoKeys 177, pp. 17-24 : 17

Utricularia lihengiae C. L. Long & Z. Cheng sp. nov. “李恒挖耳草” (Li Heng Wa Er Cao) Figure 2 , Table 1

Diagnosis.

U. lihengiae is similar to U. bifida L. (1753: 18), but differs by the inflorescences 2-4 cm long (vs. mostly 10-20 cm long in U. bifida ), calyx upper and lower with apex acuminate (vs. calyx upper lobe, apex obtuse, calyx lower lobe, apex rounded or very shortly bifid in U. bifida ), 3-5 dark purple stripes on the upper corolla lip, 3 dark purple stripes on lower corolla lip (vs. absent in the upper and lower corolla lip in U. bifida ); U. lihengiae is similar to U. scandens Benj. (1847: 309), but differs by the smaller inflorescence 2-4 cm long (vs. mostly 15-35 cm long in U. scandens ), peduncle of U. lihengiae is erect (vs. peduncle usually twining in U. scandens ), calyx lower lobe with apex acuminate (vs. calyx lower lobe with apex rounded or very shortly bifid in U. scandens ), upper calyx lobe of U. lihengiae is shorter than upper corolla lip (vs. upper calyx lobe longer than upper corolla lip in U. scandens ), 3-5 dark purple stripes on the upper corolla lip, 3 dark purple stripes on lower corolla lip (vs. absent in the upper and lower corolla lip in U. scandens ).

Type.

China, Yunnan Province, Nujiang Lisu Autonomous Prefecture, Gongshan Dulong and Nu Autonomous County, Dulongjiang Township , 2844 m a.s.l., 27°50'36"N, 98°27'48"E, 3 September, 2019, Chun Lin Long & Zhuo Cheng DXH066, (holotype: KUN!; isotype: KUN!) .

Description.

Small annual herbs. Rhizoids few, capillary, 0.5 cm to 2 cm long, 0.15-0.3 mm thick, with numerous short papillose branches. Stolons few, capillary, branched, up to 4 cm long, ca. 0.2 mm thick, the internodes mostly 2-4 mm long. Leaves few, from the stolon nodes, petiolate, the lamina narrowly linear, with apex rounded or subacute, 1-nerved, 0.5-1 mm wide, total length up to 1.5 cm. Traps rather few on the stolon internodes and leaves, globose, shortly stalked, 0.5-1 mm long, the mouth basal with 2 simple, subulate, reflexed, dorsal appendages and with a ± distinct rounded swelling on the ventral side of the mouth or on the adjacent distal part of the stalk. Inflorescence erect, solitary, simple or rarely sparsely branched, 2-4 cm long; peduncle terete, glabrous, 0.2-0.4 mm thick. Scales few, similar to the bracts. Bracts basifixed, ovate, with apex obtuse to acute, 1-2 mm long, 1-5 nerved. Bracteoles subulate, with apex acute, much shorter than the bract. Flowers 1-2, the raceme axis elongate; pedicels spreading at anthesis, decurved in fruit, capillary, broadly winged, 2-6 mm long. Calyx lobes slightly unequal, broadly ovate, 1-3 mm long, the upper lobe with apex obtuse to acute, the lower lobe slightly smaller with apex obtuse to acute. Corolla yellow, 3-7 mm long; upper lip slightly constricted below the middle, the superior part oblong or oblong-obovate, with apex rounded, bearing 3-5 dark purple stripes on the upper corolla lip, radial, the inferior part broadly ovate-deltoid; lower lip limb galeate, approximately circular, the base with a prominent rounded swelling, the apical margin rounded; palate margin ciliate; 3 dark purple stripes on the lower corolla lip, parallel; spur subulate, with apex acute, curved, about as long as and widely diverging from the lower lip. Filaments straight, 1 mm long, the anther thecae distinct. Ovary ovoid, dorsiventrally compressed; style distinct; stigma lower lip semicircular, the upper lip very short or ± obsolete. Capsule broadly ellipsoid, dorsiventrally compressed, 2.5-3 mm long, the wall uniformly membranous, dehiscing by dorsal and ventral longitudinal slits. Seeds obliquely obovoid, the major end with apex subtruncate, 0.4-0.5 mm long, the testa cells elongate with anticlinal boundaries much raised and longitudinally striate, somewhat sinuate, the periclinal walls tabular, conspicuously longitudinally striate.

Distribution and habitat.

The only known locality of this taxon is in Dulongjiang Township, Gongshan Dulong and Nu Autonomous County, Northwest Yunnan, China. The site is located in an open area in a primeval forest dominated by Fagaceae , Magnoliaceae and Ericaceae . The observed population is very small, with fewer than 80 plants growing in the moss amongst damp grass on the roadside, accompanied by the moss Polytrichum commune Hedwig (1801: 88), as well as Vaccinium chaetothrix Sleumer (1941: 432), and Acorus tatarinowii Schott (1859: 101). The elevation is 2800-2900 metres above sea level. The climate here is rainy and humid, with rain falling for most of the year.

Phenology.

Flowering and fruiting occurs from August to November.

Etymology.

Named in honor of Prof. Li Heng, a Chinese botanist who has made significant contributions to the knowledge of the flora of Dulongjiang region.

Conservation status.

This species has not been recorded or described so far, and there is only one known site in Dulongjiang region, which is relatively unknown to botanists. In addition, Utricularia lihengiae is very small and has a short flowering period, making it easily overlooked. This species satisfies the IUCN 3.1 Red List CR (Critically Endangered) Criteria B1ab(ii,iii)+2ab(i,ii,iii) ( IUCN 2012), which has an EOO (Extent of occurrence) <100 km2 and AOO (Area of occupancy) <10 km2, it may be classified as "critically endangered" (CR). The distribution site of Utricularia lihengiae is next to the road, which is at great risk of human disturbance and extreme weather, such as tourist activities, road building, grazing and landslides. Additionally, regional management in pursuit of economic development is likely to pose a threat through trampling and pollution of soil and water, causing negative impacts to the small and fragile habitat.

Taxonomic notes.

The new species belongs to Utricularia section Oligocista due to the following characters: traps globose, the mouth basal with 2 simple subulate dorsal appendages and leaves linear to obovate ( Taylor 1989). There were five species belonging to Utricularia section Oligocista in China prior to the discovery of U. lihengiae . From the perspective of geographical distribution, U. bifida and U. scandens are both distributed in Yunnan, U. scandens , is mainly distributed in northwestern Yunnan, whereas U. bifida is mainly found in south Yunnan. According to the key to the species of Utricularia occurring in China ( Li 2007), the morphology of U. lihengiae is similar to U. bifida and U. scandens in the yellow corolla. However, it can be clearly distinguished by the dark purple stripes of the corolla, shorter inflorescence and by the shape of the calyx lobes. A comparative summary of the characters that differentiate these three taxa is presented in Table 1 .

Additional specimens examined.

China, Yunnan Province, Nujiang Lisu Autonomous Prefecture, Gongshan Dulong and Nu Autonomous County, Dulongjiang Township , 2844 m a.s.l., 27°50'36"N, 98°27'48"E, 3 September 2019, Chun Lin Long & Zhuo Cheng DXH066, Chun Lin Long & Zhuo Cheng DXH067, Chun Lin Long & Zhuo Cheng DXH068, Chun Lin Long & Zhuo Cheng DXH069, Chun Lin Long & Zhuo Cheng DXH070 (KUN!) .

Specimens of Utricularia bifida examined.

CHINA. Guangdong: Renhua County, 16 November 1973, C.J. Huang & Y.T. Zhang 077 (PE); Deqing County, 5 August 1958, Y.G. Liu 01303 (PE), 2 August 1930, J.L. Zuo 22497 (IBK), 6 July 1958, X.G. Li 202078 (IBK). Guangxi: Yongning District, 6 July 1984, Z.Y. Li 10984 (PE); Lingui County, 5 September 1997, G.Z. Li 16229 (PE), 11 October 1958, Y.K Li 402165 (IBK), 19 October 1948, S.G. Li 200104 (IBK). Yunnan, 2 June 1939, M.K. Li 1698 (WUK). Jiangxi, 19 September 1963, J.S. Yue et al. 3983 (IBSC), 26 June 1932, Y. Jiang 9967 (IBSC).

Figures

Figure 2. Utricularia lihengiae (A-J) A habitat B whole plant C traps and laminar leaves D leaf E calyx upper lobe F calyx lower lobe G bracts H-J frontal, dorsal and lateral view of the flower (A-J Photos by Z. Cheng.).